Qi Zheng [Fri, 27 Mar 2026 10:16:30 +0000 (18:16 +0800)]
mm: memcontrol: correct the nr_pages parameter type of mem_cgroup_update_lru_size()
The nr_pages parameter of mem_cgroup_update_lru_size() represents a page
count. During the reparenting of LRU folios, the value passed to it can
potentially exceed the maximum value of a 32-bit integer. It should be
declared as long instead of int to match the types used in lruvec size
accounting and to prevent possible overflow.
Update the parameter type to long to ensure correctness.
Link: https://lore.kernel.org/fd4140de44fa0a3978e4e2426731187fe8625f0b.1774604356.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Fri, 27 Mar 2026 10:16:29 +0000 (18:16 +0800)]
mm: memcontrol: change val type to long in __mod_memcg_{lruvec_}state()
The __mod_memcg_state() and __mod_memcg_lruvec_state() functions are also
used to reparent non-hierarchical stats. In this scenario, the values
passed to them are accumulated statistics that might be extremely large
and exceed the upper limit of a 32-bit integer.
Change the val parameter type from int to long in these functions and
their corresponding tracepoints (memcg_rstat_stats) to prevent potential
overflow issues.
After that, in memcg_state_val_in_pages(), if the passed val is negative,
the expression val * unit / PAGE_SIZE could be implicitly converted to a
massive positive number when compared with 1UL in the max() macro. This
leads to returning an incorrect massive positive value.
Fix this by using abs(val) to calculate the magnitude first, and then
restoring the sign of the value before returning the result.
Additionally, use mult_frac() to prevent potential overflow during the
multiplication of val and unit.
Link: https://lore.kernel.org/70a9440e49c464b4dca88bcabc6b491bd335c9f0.1774604356.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reported-by: Harry Yoo (Oracle) <harry@kernel.org> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Fri, 27 Mar 2026 10:16:28 +0000 (18:16 +0800)]
mm: memcontrol: correct the type of stats_updates to unsigned long
Patch series "fix unexpected type conversions and potential overflows",
v3.
As Harry Yoo pointed out [1], in scenarios where massive state updates
occur (e.g., during the reparenting of LRU folios), the values passed to
memcg stat update functions can accumulate and exceed the upper limit of a
32-bit integer.
If the parameter types are not large enough (like 'int') or are handled
incorrectly, it can lead to severe truncation, potential overflow issues,
and unexpected type conversion bugs.
This series aims to address these issues by correcting the parameter types
in the relevant functions, and by fixing an implicit conversion bug in
memcg_state_val_in_pages().
This patch (of 3):
The memcg_rstat_updated() tracks updates for vmstats_percpu->state and
lruvec_stats_percpu->state. Since these state values are of type long,
change the val parameter passed to memcg_rstat_updated() to long as well.
Correspondingly, change the type of stats_updates in struct
memcg_vmstats_percpu and struct memcg_vmstats from unsigned int and
atomic_t to unsigned long and atomic_long_t respectively to prevent
potential overflow when handling large state updates during the
reparenting of LRU folios.
Link: https://lore.kernel.org/cover.1774604356.git.zhengqi.arch@bytedance.com Link: https://lore.kernel.org/a5b0b468e7b4fe5f26c50e36d5d016f16d92f98f.1774604356.git.zhengqi.arch@bytedance.com Link: https://lore.kernel.org/all/acDxaEgnqPI-Z4be@hyeyoo/ Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:51 +0000 (19:52 +0800)]
mm: lru: add VM_WARN_ON_ONCE_FOLIO to lru maintenance helpers
We must ensure the folio is deleted from or added to the correct lruvec
list. So, add VM_WARN_ON_ONCE_FOLIO() to catch invalid users. The
VM_BUG_ON_PAGE() in move_pages_to_lru() can be removed as
add_page_to_lru_list() will perform the necessary check.
Link: https://lore.kernel.org/2c90fc006d9d730331a3caeef96f7e5dabe2036d.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:50 +0000 (19:52 +0800)]
mm: memcontrol: eliminate the problem of dying memory cgroup for LRU folios
Now that everything is set up, switch folio->memcg_data pointers to
objcgs, update the accessors, and execute reparenting on cgroup death.
Finally, folio->memcg_data of LRU folios and kmem folios will always point
to an object cgroup pointer. The folio->memcg_data of slab folios will
point to an vector of object cgroups.
Link: https://lore.kernel.org/80cb7af198dc6f2173fe616d1207a4c315ece141.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:49 +0000 (19:52 +0800)]
mm: memcontrol: convert objcg to be per-memcg per-node type
Convert objcg to be per-memcg per-node type, so that when reparent LRU
folios later, we can hold the lru lock at the node level, thus avoiding
holding too many lru locks at once.
[zhengqi.arch@bytedance.com: reset pn->orig_objcg to NULL] Link: https://lore.kernel.org/20260309112939.31937-1-qi.zheng@linux.dev
[akpm@linux-foundation.org: fix comment typo, per Usama. Reflow comment to 80 cols]
[devnexen@gmail.com: fix obj_cgroup leak in mem_cgroup_css_online() error path] Link: https://lore.kernel.org/20260322193631.45457-1-devnexen@gmail.com
[devnexen@gmail.com: add newline, per Qi Zheng] Link: https://lore.kernel.org/20260323063007.7783-1-devnexen@gmail.com Link: https://lore.kernel.org/56c04b1c5d54f75ccdc12896df6c1ca35403ecc3.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Signed-off-by: David Carlier <devnexen@gmail.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Usama Arif <usama.arif@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:48 +0000 (19:52 +0800)]
mm: memcontrol: prepare for reparenting non-hierarchical stats
To resolve the dying memcg issue, we need to reparent LRU folios of child
memcg to its parent memcg. This could cause problems for non-hierarchical
stats.
As Yosry Ahmed pointed out:
In short, if memory is charged to a dying cgroup at the time of
reparenting, when the memory gets uncharged the stats updates will occur
at the parent. This will update both hierarchical and non-hierarchical
stats of the parent, which would corrupt the parent's non-hierarchical
stats (because those counters were never incremented when the memory was
charged).
Now we have the following two types of non-hierarchical stats, and they
are only used in CONFIG_MEMCG_V1:
a. memcg->vmstats->state_local[i]
b. pn->lruvec_stats->state_local[i]
To ensure that these non-hierarchical stats work properly, we need to
reparent these non-hierarchical stats after reparenting LRU folios. To
this end, this commit makes the following preparations:
1. implement reparent_state_local() to reparent non-hierarchical stats
2. make css_killed_work_fn() to be called in rcu work, and implement
get_non_dying_memcg_start() and get_non_dying_memcg_end() to avoid race
between mod_memcg_state()/mod_memcg_lruvec_state()
and reparent_state_local()
Link: https://lore.kernel.org/e862995c45a7101a541284b6ebee5e5c32c89066.1772711148.git.zhengqi.arch@bytedance.com Co-developed-by: Yosry Ahmed <yosry@kernel.org> Signed-off-by: Yosry Ahmed <yosry@kernel.org> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:46 +0000 (19:52 +0800)]
mm: workingset: use lruvec_lru_size() to get the number of lru pages
For cgroup v2, count_shadow_nodes() is the only place to read
non-hierarchical stats (lruvec_stats->state_local). To avoid the need to
consider cgroup v2 during subsequent non-hierarchical stats reparenting,
use lruvec_lru_size() instead of lruvec_page_state_local() to get the
number of lru pages.
For NR_SLAB_RECLAIMABLE_B and NR_SLAB_UNRECLAIMABLE_B cases, it appears
that the statistics here have already been problematic for a while since
slab pages have been reparented. So just ignore it for now.
Link: https://lore.kernel.org/b1d448c667a8fb377c3390d9aba43bdb7e4d5739.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:44 +0000 (19:52 +0800)]
mm: vmscan: prepare for reparenting MGLRU folios
Similar to traditional LRU folios, in order to solve the dying memcg
problem, we also need to reparenting MGLRU folios to the parent memcg when
memcg offline.
However, there are the following challenges:
1. Each lruvec has between MIN_NR_GENS and MAX_NR_GENS generations, the
number of generations of the parent and child memcg may be different,
so we cannot simply transfer MGLRU folios in the child memcg to the
parent memcg as we did for traditional LRU folios.
2. The generation information is stored in folio->flags, but we cannot
traverse these folios while holding the lru lock, otherwise it may
cause softlockup.
3. In walk_update_folio(), the gen of folio and corresponding lru size
may be updated, but the folio is not immediately moved to the
corresponding lru list. Therefore, there may be folios of different
generations on an LRU list.
4. In lru_gen_del_folio(), the generation to which the folio belongs is
found based on the generation information in folio->flags, and the
corresponding LRU size will be updated. Therefore, we need to update
the lru size correctly during reparenting, otherwise the lru size may
be updated incorrectly in lru_gen_del_folio().
Finally, this patch chose a compromise method, which is to splice the lru
list in the child memcg to the lru list of the same generation in the
parent memcg during reparenting. And in order to ensure that the parent
memcg has the same generation, we need to increase the generations in the
parent memcg to the MAX_NR_GENS before reparenting.
Of course, the same generation has different meanings in the parent and
child memcg, this will cause confusion in the hot and cold information of
folios. But other than that, this method is simple enough, the lru size
is correct, and there is no need to consider some concurrency issues (such
as lru_gen_del_folio()).
To prepare for the above work, this commit implements the specific
functions, which will be used during reparenting.
[zhengqi.arch@bytedance.com: use list_splice_tail_init() to reparent child folios] Link: https://lore.kernel.org/20260324114937.28569-1-qi.zheng@linux.dev Link: https://lore.kernel.org/e75050354cdbc42221a04f7cf133292b61105548.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Suggested-by: Harry Yoo <harry.yoo@oracle.com> Suggested-by: Imran Khan <imran.f.khan@oracle.com> Acked-by: Harry Yoo <harry.yoo@oracle.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:43 +0000 (19:52 +0800)]
mm: vmscan: prepare for reparenting traditional LRU folios
To resolve the dying memcg issue, we need to reparent LRU folios of child
memcg to its parent memcg. For traditional LRU list, each lruvec of every
memcg comprises four LRU lists. Due to the symmetry of the LRU lists, it
is feasible to transfer the LRU lists from a memcg to its parent memcg
during the reparenting process.
This commit implements the specific function, which will be used during
the reparenting process.
Link: https://lore.kernel.org/a92d217a9fc82bd0c401210204a095caaf615b1c.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Muchun Song <muchun.song@linux.dev> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:42 +0000 (19:52 +0800)]
mm: memcontrol: prepare for reparenting LRU pages for lruvec lock
The following diagram illustrates how to ensure the safety of the folio
lruvec lock when LRU folios undergo reparenting.
In the folio_lruvec_lock(folio) function:
rcu_read_lock();
retry:
lruvec = folio_lruvec(folio);
/* There is a possibility of folio reparenting at this point. */
spin_lock(&lruvec->lru_lock);
if (unlikely(lruvec_memcg(lruvec) != folio_memcg(folio))) {
/*
* The wrong lruvec lock was acquired, and a retry is required.
* This is because the folio resides on the parent memcg lruvec
* list.
*/
spin_unlock(&lruvec->lru_lock);
goto retry;
}
/* Reaching here indicates that folio_memcg() is stable. */
In the memcg_reparent_objcgs(memcg) function:
spin_lock(&lruvec->lru_lock);
spin_lock(&lruvec_parent->lru_lock);
/* Transfer folios from the lruvec list to the parent's. */
spin_unlock(&lruvec_parent->lru_lock);
spin_unlock(&lruvec->lru_lock);
After acquiring the lruvec lock, it is necessary to verify whether the
folio has been reparented. If reparenting has occurred, the new lruvec
lock must be reacquired. During the LRU folio reparenting process, the
lruvec lock will also be acquired (this will be implemented in a
subsequent patch). Therefore, folio_memcg() remains unchanged while the
lruvec lock is held.
Given that lruvec_memcg(lruvec) is always equal to folio_memcg(folio)
after the lruvec lock is acquired, the lruvec_memcg_debug() check is
redundant. Hence, it is removed.
This patch serves as a preparation for the reparenting of LRU folios.
Link: https://lore.kernel.org/23f22cbb1419f277a3483018b32158ae2b86c666.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Harry Yoo <harry.yoo@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:41 +0000 (19:52 +0800)]
mm: do not open-code lruvec lock
Now we have lruvec_unlock(), lruvec_unlock_irq() and
lruvec_unlock_irqrestore(), but no the paired lruvec_lock(),
lruvec_lock_irq() and lruvec_lock_irqsave().
There is currently no use case for lruvec_lock_irqsave(), so only
introduce lruvec_lock_irq(), and change all open-code places to use this
helper function. This looks cleaner and prepares for reparenting LRU
pages, preventing user from missing RCU lock calls due to open-code lruvec
lock.
Link: https://lore.kernel.org/2d0bafe7564e17ece46dfd58197af22ce57017dc.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Muchun Song <muchun.song@linux.dev> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:40 +0000 (19:52 +0800)]
mm: workingset: prevent lruvec release in workingset_activation()
In the near future, a folio will no longer pin its corresponding memory
cgroup. So an lruvec returned by folio_lruvec() could be released without
the rcu read lock or a reference to its memory cgroup.
In the current patch, the rcu read lock is employed to safeguard against
the release of the lruvec in workingset_activation().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/c6130476affbba0a7d309a887c3df11e0167990b.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:39 +0000 (19:52 +0800)]
mm: swap: prevent lruvec release in lru_gen_clear_refs()
In the near future, a folio will no longer pin its corresponding memory
cgroup. So an lruvec returned by folio_lruvec() could be released without
the rcu read lock or a reference to its memory cgroup.
In the current patch, the rcu read lock is employed to safeguard against
the release of the lruvec in lru_gen_clear_refs().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/986cd26227191a48a7c34a2a15812d361f4ebd53.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:38 +0000 (19:52 +0800)]
mm: zswap: prevent lruvec release in zswap_folio_swapin()
In the near future, a folio will no longer pin its corresponding memory
cgroup. So an lruvec returned by folio_lruvec() could be released without
the rcu read lock or a reference to its memory cgroup.
In the current patch, the rcu read lock is employed to safeguard against
the release of the lruvec in zswap_folio_swapin().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/02b3f76ee8d1132f69ac5baaedce38fb82b09a48.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:37 +0000 (19:52 +0800)]
mm: workingset: prevent lruvec release in workingset_refault()
In the near future, a folio will no longer pin its corresponding memory
cgroup. So an lruvec returned by folio_lruvec() could be released without
the rcu read lock or a reference to its memory cgroup.
In the current patch, the rcu read lock is employed to safeguard against
the release of the lruvec in workingset_refault().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/e3a8c19a9b18422b43213f6c89c451c5b6ca1577.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Yosry Ahmed <yosry@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:36 +0000 (19:52 +0800)]
mm: zswap: prevent memory cgroup release in zswap_compress()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in zswap_compress().
Link: https://lore.kernel.org/340f315050fb8a67caaf01b4836d4f38a41cf1a8.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Muchun Song <muchun.song@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:35 +0000 (19:52 +0800)]
mm: thp: prevent memory cgroup release in folio_split_queue_lock{_irqsave}()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in folio_split_queue_lock{_irqsave}().
Link: https://lore.kernel.org/ca2957c0df1126b2c71b40c738018fd5255525a6.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:34 +0000 (19:52 +0800)]
mm: workingset: prevent memory cgroup release in lru_gen_eviction()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in lru_gen_eviction().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/f37e8ae2d84ddc690813d834cd75735d52d1bc78.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:33 +0000 (19:52 +0800)]
mm: memcontrol: prevent memory cgroup release in mem_cgroup_swap_full()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in mem_cgroup_swap_full().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/21d1abab7342615745ea4c18a88237335ab44d13.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:32 +0000 (19:52 +0800)]
mm: mglru: prevent memory cgroup release in mglru
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in mglru.
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/9d887662a9d39c425742dd8468e3123316bccfe3.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:31 +0000 (19:52 +0800)]
mm: migrate: prevent memory cgroup release in folio_migrate_mapping()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In __folio_migrate_mapping(), the rcu read lock is employed to safeguard
against the release of the memory cgroup in folio_migrate_mapping().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/0f156c2f1188f256855617953f8305f43e066065.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:30 +0000 (19:52 +0800)]
mm: page_io: prevent memory cgroup release in page_io module
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in swap_writeout() and
bio_associate_blkg_from_page().
This serves as a preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/7c3708358412fb02c482d0985feb5e9513a863ef.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:29 +0000 (19:52 +0800)]
mm: memcontrol: prevent memory cgroup release in count_memcg_folio_events()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in count_memcg_folio_events().
This serves as a preparatory measure for the reparenting of the
LRU pages.
Link: https://lore.kernel.org/dea6aa0389367f7fd6b715c8837a2cf7506bd889.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:28 +0000 (19:52 +0800)]
writeback: prevent memory cgroup release in writeback module
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the function get_mem_cgroup_css_from_folio() and the
rcu read lock are employed to safeguard against the release of the memory
cgroup.
This serves as a preparatory measure for the reparenting of the
LRU pages.
Link: https://lore.kernel.org/645f99bc344575417f67def3744f975596df2793.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:27 +0000 (19:52 +0800)]
buffer: prevent memory cgroup release in folio_alloc_buffers()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the function get_mem_cgroup_from_folio() is employed
to safeguard against the release of the memory cgroup. This serves as a
preparatory measure for the reparenting of the LRU pages.
Link: https://lore.kernel.org/d6d48fdcf329c549373ac0a1c80fd9f38067e34e.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:26 +0000 (19:52 +0800)]
mm: memcontrol: prevent memory cgroup release in get_mem_cgroup_from_folio()
In the near future, a folio will no longer pin its corresponding memory
cgroup. To ensure safety, it will only be appropriate to hold the rcu
read lock or acquire a reference to the memory cgroup returned by
folio_memcg(), thereby preventing it from being released.
In the current patch, the rcu read lock is employed to safeguard against
the release of the memory cgroup in get_mem_cgroup_from_folio().
This serves as a preparatory measure for the reparenting of the
LRU pages.
Link: https://lore.kernel.org/a5a64c6173a566bd21534606aeaaa9220cb1366d.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:25 +0000 (19:52 +0800)]
mm: memcontrol: return root object cgroup for root memory cgroup
Memory cgroup functions such as get_mem_cgroup_from_folio() and
get_mem_cgroup_from_mm() return a valid memory cgroup pointer, even for
the root memory cgroup. In contrast, the situation for object cgroups has
been different.
Previously, the root object cgroup couldn't be returned because it didn't
exist. Now that a valid root object cgroup exists, for the sake of
consistency, it's necessary to align the behavior of object-cgroup-related
operations with that of memory cgroup APIs.
Link: https://lore.kernel.org/e9c3f40ba7681d9753372d4ee2ac7a0216848b95.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:24 +0000 (19:52 +0800)]
mm: memcontrol: allocate object cgroup for non-kmem case
To allow LRU page reparenting, the objcg infrastructure is no longer
solely applicable to the kmem case. In this patch, we extend the scope of
the objcg infrastructure beyond the kmem case, enabling LRU folios to
reuse it for folio charging purposes.
It should be noted that LRU folios are not accounted for at the root
level, yet the folio->memcg_data points to the root_mem_cgroup. Hence,
the folio->memcg_data of LRU folios always points to a valid pointer.
However, the root_mem_cgroup does not possess an object cgroup.
Therefore, we also allocate an object cgroup for the root_mem_cgroup.
Link: https://lore.kernel.org/b77274aa8e3f37c419bedf4782943fd5885dda82.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Chen Ridong <chenridong@huawei.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:23 +0000 (19:52 +0800)]
mm: vmscan: refactor move_folios_to_lru()
In a subsequent patch, we'll reparent the LRU folios. The folios that are
moved to the appropriate LRU list can undergo reparenting during the
move_folios_to_lru() process. Hence, it's incorrect for the caller to
hold a lruvec lock. Instead, we should utilize the more general interface
of folio_lruvec_relock_irq() to obtain the correct lruvec lock.
This patch involves only code refactoring and doesn't introduce any
functional changes.
Link: https://lore.kernel.org/6f1dac88b61e2e3cb7a3e90bacdf06b654acfc15.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chen Ridong <chenridong@huawei.com> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Qi Zheng [Thu, 5 Mar 2026 11:52:22 +0000 (19:52 +0800)]
mm: vmscan: prepare for the refactoring the move_folios_to_lru()
Once we refactor move_folios_to_lru(), its callers will no longer have to
hold the lruvec lock; For shrink_inactive_list(), shrink_active_list() and
evict_folios(), IRQ disabling is only needed for __count_vm_events() and
__mod_node_page_state().
To avoid using local_irq_disable() on the PREEMPT_RT kernel, let's make
all callers of move_folios_to_lru() use IRQ-safed count_vm_events() and
mod_node_page_state().
Link: https://lore.kernel.org/b3a202f1787b0857bb6cbe059fffb8edefaf67b7.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Reviewed-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Acked-by: Muchun Song <muchun.song@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:21 +0000 (19:52 +0800)]
mm: rename unlock_page_lruvec_irq and its variants
It is inappropriate to use folio_lruvec_lock() variants in conjunction
with unlock_page_lruvec() variants, as this involves the inconsistent
operation of locking a folio while unlocking a page. To rectify this, the
functions unlock_page_lruvec{_irq, _irqrestore} are renamed to
lruvec_unlock{_irq,_irqrestore}.
Link: https://lore.kernel.org/4e5e05271a250df4d1812e1832be65636a78c957.1772711148.git.zhengqi.arch@bytedance.com Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Acked-by: David Hildenbrand (Red Hat) <david@kernel.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Muchun Song [Thu, 5 Mar 2026 11:52:19 +0000 (19:52 +0800)]
mm: memcontrol: remove dead code of checking parent memory cgroup
Patch series "Eliminate Dying Memory Cgroup", v6.
Introduction
============
This patchset is intended to transfer the LRU pages to the object cgroup
without holding a reference to the original memory cgroup in order to
address the issue of the dying memory cgroup. A consensus has already
been reached regarding this approach recently [1].
Background
==========
The issue of a dying memory cgroup refers to a situation where a memory
cgroup is no longer being used by users, but memory (the metadata
associated with memory cgroups) remains allocated to it. This situation
may potentially result in memory leaks or inefficiencies in memory
reclamation and has persisted as an issue for several years. Any memory
allocation that endures longer than the lifespan (from the users'
perspective) of a memory cgroup can lead to the issue of dying memory
cgroup. We have exerted greater efforts to tackle this problem by
introducing the infrastructure of object cgroup [2].
Presently, numerous types of objects (slab objects, non-slab kernel
allocations, per-CPU objects) are charged to the object cgroup without
holding a reference to the original memory cgroup. The final allocations
for LRU pages (anonymous pages and file pages) are charged at allocation
time and continues to hold a reference to the original memory cgroup until
reclaimed.
File pages are more complex than anonymous pages as they can be shared
among different memory cgroups and may persist beyond the lifespan of the
memory cgroup. The long-term pinning of file pages to memory cgroups is a
widespread issue that causes recurring problems in practical scenarios
[3]. File pages remain unreclaimed for extended periods. Additionally,
they are accessed by successive instances (second, third, fourth, etc.) of
the same job, which is restarted into a new cgroup each time. As a
result, unreclaimable dying memory cgroups accumulate, leading to memory
wastage and significantly reducing the efficiency of page reclamation.
Fundamentals
============
A folio will no longer pin its corresponding memory cgroup. It is
necessary to ensure that the memory cgroup or the lruvec associated with
the memory cgroup is not released when a user obtains a pointer to the
memory cgroup or lruvec returned by folio_memcg() or folio_lruvec().
Users are required to hold the RCU read lock or acquire a reference to the
memory cgroup associated with the folio to prevent its release if they are
not concerned about the binding stability between the folio and its
corresponding memory cgroup. However, some users of folio_lruvec() (i.e.,
the lruvec lock) desire a stable binding between the folio and its
corresponding memory cgroup. An approach is needed to ensure the
stability of the binding while the lruvec lock is held, and to detect the
situation of holding the incorrect lruvec lock when there is a race
condition during memory cgroup reparenting. The following four steps are
taken to achieve these goals.
1. The first step to be taken is to identify all users of both functions
(folio_memcg() and folio_lruvec()) who are not concerned about binding
stability and implement appropriate measures (such as holding a RCU read
lock or temporarily obtaining a reference to the memory cgroup for a
brief period) to prevent the release of the memory cgroup.
2. Secondly, the following refactoring of folio_lruvec_lock() demonstrates
how to ensure the binding stability from the user's perspective of
folio_lruvec().
From the perspective of memory cgroup removal, the entire reparenting
process (altering the binding relationship between folio and its memory
cgroup and moving the LRU lists to its parental memory cgroup) should be
carried out under both the lruvec lock of the memory cgroup being removed
and the lruvec lock of its parent.
3. Finally, transfer the LRU pages to the object cgroup without holding a
reference to the original memory cgroup.
Effect
======
Finally, it can be observed that the quantity of dying memory cgroups will
not experience a significant increase if the following test script is
executed to reproduce the issue.
#!/bin/bash
# Create a temporary file 'temp' filled with zero bytes
dd if=/dev/zero of=temp bs=4096 count=1
# Display memory-cgroup info from /proc/cgroups
cat /proc/cgroups | grep memory
for i in {0..2000}
do
mkdir /sys/fs/cgroup/memory/test$i
echo $$ > /sys/fs/cgroup/memory/test$i/cgroup.procs
# Potentially create a dying memory cgroup
rmdir /sys/fs/cgroup/memory/test$i
done
# Display memory-cgroup info after test
cat /proc/cgroups | grep memory
rm -f temp log
This patch (of 33):
Since the no-hierarchy mode has been deprecated after the commit:
commit bef8620cd8e0 ("mm: memcg: deprecate the non-hierarchical mode").
As a result, parent_mem_cgroup() will not return NULL except when passing
the root memcg, and the root memcg cannot be offline. Hence, it's safe to
remove the check on the returned value of parent_mem_cgroup(). Remove the
corresponding dead code.
Link: https://lore.kernel.org/f4481291bf8c6561dd8949045b5a1ed4008a6b63.1772711148.git.zhengqi.arch@bytedance.com Link: https://lore.kernel.org/linux-mm/Z6OkXXYDorPrBvEQ@hm-sls2/ Link: https://lwn.net/Articles/895431/ Link: https://github.com/systemd/systemd/pull/36827 Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Harry Yoo <harry.yoo@oracle.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Allen Pais <apais@linux.microsoft.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: David Hildenbrand <david@kernel.org> Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com> Cc: Hugh Dickins <hughd@google.com> Cc: Imran Khan <imran.f.khan@oracle.com> Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Usama Arif <usamaarif642@gmail.com> Cc: Vlastimil Babka <vbabka@kernel.org> Cc: Wei Xu <weixugc@google.com> Cc: Yosry Ahmed <yosry@kernel.org> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Lorenzo Stoakes [Mon, 13 Apr 2026 10:57:13 +0000 (11:57 +0100)]
mm/vma: remove __vma_check_mmap_hook()
Commit c50ca15dd496 ("mm: add vm_ops->mapped hook") introduced
__vma_check_mmap_hook() in order to assert that a driver doesn't
incorrectly implement both an f_op->mmap() and a vm_ops->mapped hook, the
latter of which would not ultimately get invoked.
However, this did not correctly account for stacked drivers (or drivers
that otherwise use the compatibility layer) which might recursively call
an mmap_prepare hook via the compatibility layer.
Thus the nested mmap_prepare() invocation might result in a VMA which has
vm_ops->mapped set with an overlaying mmap() hook, causing the
__vma_check_mmap_hook() to fail in vfs_mmap(), wrongly failing the
operation.
This patch resolves this by simply removing the check, as we can't be
certain that an mmap() hook doesn't at some point invoke the compatibility
layer, and it's not worth trying to track it.
Link: https://lore.kernel.org/20260413105713.92625-1-ljs@kernel.org Fixes: c50ca15dd496 ("mm: add vm_ops->mapped hook") Reported-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com> Closes: https://lore.kernel.org/all/adx2ws5z0NMIe5Yj@shinmob/ Signed-off-by: Lorenzo Stoakes <ljs@kernel.org> Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Tested-by: Shinichiro Kawasaki <shinichiro.kawasaki@wdc.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Jan Kara <jack@suse.cz> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Dan Carpenter [Fri, 10 Apr 2026 15:24:49 +0000 (00:24 +0900)]
ntfs: fix potential 32-bit truncation in ntfs_write_cb()
Smatch warned that the bitwise negation in ntfs_write_cb() might lead to
unintended truncation. Casting the block size to loff_t before bitwise
negation prevents the upper 32 bits of pos from being incorrectly zeroed
out during the calculation of new_vcn.
Signed-off-by: Dan Carpenter <error27@gmail.com> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
ntfs: fix uninitialized variable in ntfs_map_runlist_nolock
Smatch reported that ctx_needs_reset could be used uninitialized if
ntfs_map_runlist_nolock() fails early when a search context is provided.
Specifically, if the function returns -EIO because the attribute is
resident, the code jumps to err_out. This initializes ctx_needs_reset to
false to satisfy the static checker.
Reported-by: Dan Carpenter <error27@gmail.com> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
ntfs: fix uninitialized variables in ntfs_ea_set_wsl_inode()
Smatch reported uninitialized symbol warnings in ntfs_ea_set_wsl_inode()
and __ntfs_create(). In ntfs_ea_set_wsl_inode(), the err variable could be
returned without initialization if no flags are set and rdev is zero.
Additionally, ea_size might remain uninitialized from the caller's
perspective if no EA operations are performed. While these cases might not
be triggered under current logic, we initialize them to zero to satisfy
the static checker.
Reported-by: Dan Carpenter <error27@gmail.com> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
ntfs: fix uninitialized pointer in ntfs_write_mft_block
Smatch reported that the variable rl could be used uninitialized in
ntfs_write_mft_block(). After analyzing the code,
when vol->cluster_size == NTFS_BLOCK_SIZE (512), it is smaller than
folio_size, so rl is guaranteed to be initialized. If vol->cluster_size
is larger, the condition to access rl becomes false, so a runtime error is
not expected to occur. However, to make the static checker happy,
this patch initializes rl to NULL and adds an explicit check before
its usage.
Reported-by: Dan Carpenter <error27@gmail.com> Reviewed-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Hyunchul Lee [Wed, 1 Apr 2026 07:24:57 +0000 (16:24 +0900)]
ntfs: zero out stale data in straddle block beyond initialized_size
ntfs_read_iomap_begin_non_resident() rounds up MAPPED extents
to the block boundary of initialized_size. This ensures that
any subsequent blocks are treated as IOMAP_UNWRITTEN, but
it also causes the "straddle block" containing initialized_size
to be read from disk. The disk data beyond initialized_size in
this block is stale and must be zeroed to prevent data leakage.
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Merge tag 'mtd/for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux
Pull MTD updates from Miquel Raynal:
"MTD changes:
- mtdconcat finally makes it in, after several years of being merged
and reverted
- Baikal SoC support is being removed, so MTD bits are being removed
as well
- misc cleanups
NAND changes:
- SunXi driver support for new versions of the Allwinner NAND
controller.
- DT-binding improvements and cleanups.
- A few fixes (Realtek ECC and Winbond SPI NAND), aside with the
usual load of misc changes.
SPI NOR fixes:
- Enable die erase on MT35XU02GCBA. We knew this flash needed this
fixup since 7f77c561e227 ("mtd: spi-nor: micron-st: add TODO for
fixing mt35xu02gcba") but did not add it due to lack of hardware to
test on.
- Fix locking on some Winbond w25q series flashes.
- Fix Auto Address Increment (AAI) writes on SST that flashes that
start on odd address. The write enable latch needs to be set again
after the single byte program"
* tag 'mtd/for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (44 commits)
mtd: spinand: winbond: Declare the QE bit on W25NxxJW
mtd: spi-nor: micron-st: Enable die erase support for MT35XU02GCBA
mtd: spi-nor: winbond: Fix locking support for w25q256jw
mtd: spi-nor: sst: Fix write enable before AAI sequence
mtd: spi-nor: winbond: Fix locking support for w25q64jvm
mtd: spi-nor: winbond: Fix locking support for w25q256jwm
dt-bindings: mtd: mxc-nand: add missing compatible string and ref to nand-controller-legacy.yaml
dt-bindings: mtd: gpmi-nand: ref to nand-controller-legacy.yaml
dt-bindings: mtd: refactor NAND bindings and add nand-controller-legacy.yaml
mtd: spinand: winbond: Clarify when to enable the HS bit
mtd: rawnand: sunxi: introduce maximize variable user data length
mtd: rawnand: sunxi: fix typos in comments
mtd: rawnand: sunxi: change error prone variable name
mtd: rawnand: sunxi: remove dead code
mtd: rawnand: sunxi: make the code more self-explanatory
mtd: rawnand: sunxi: replace hard coded value by a define - take2
mtd: rawnand: sunxi: do not count BBM bytes twice
mtd: rawnand: sunxi: fix sunxi_nfc_hw_ecc_read_extra_oob
mtd: rawnand: sunxi: sunxi_nand_ooblayout_free code clarification
mtd: cmdlinepart: use a flexible array member
...
Merge tag 'ext4_for_linux-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
- Refactor code paths involved with partial block zero-out in
prearation for converting ext4 to use iomap for buffered writes
- Remove use of d_alloc() from ext4 in preparation for the deprecation
of this interface
- Replace some J_ASSERTS with a journal abort so we can avoid a kernel
panic for a localized file system error
- Simplify various code paths in mballoc, move_extent, and fast commit
- Fix rare deadlock in jbd2_journal_cancel_revoke() that can be
triggered by generic/013 when blocksize < pagesize
- Fix memory leak when releasing an extended attribute when its value
is stored in an ea_inode
- Fix various potential kunit test bugs in fs/ext4/extents.c
- Fix potential out-of-bounds access in check_xattr() with a corrupted
file system
- Make the jbd2_inode dirty range tracking safe for lockless reads
- Avoid a WARN_ON when writeback files due to a corrupted file system;
we already print an ext4 warning indicatign that data will be lost,
so the WARN_ON is not necessary and doesn't add any new information
* tag 'ext4_for_linux-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (37 commits)
jbd2: fix deadlock in jbd2_journal_cancel_revoke()
ext4: fix missing brelse() in ext4_xattr_inode_dec_ref_all()
ext4: fix possible null-ptr-deref in mbt_kunit_exit()
ext4: fix possible null-ptr-deref in extents_kunit_exit()
ext4: fix the error handling process in extents_kunit_init).
ext4: call deactivate_super() in extents_kunit_exit()
ext4: fix miss unlock 'sb->s_umount' in extents_kunit_init()
ext4: fix bounds check in check_xattrs() to prevent out-of-bounds access
ext4: zero post-EOF partial block before appending write
ext4: move pagecache_isize_extended() out of active handle
ext4: remove ctime/mtime update from ext4_alloc_file_blocks()
ext4: unify SYNC mode checks in fallocate paths
ext4: ensure zeroed partial blocks are persisted in SYNC mode
ext4: move zero partial block range functions out of active handle
ext4: pass allocate range as loff_t to ext4_alloc_file_blocks()
ext4: remove handle parameters from zero partial block functions
ext4: move ordered data handling out of ext4_block_do_zero_range()
ext4: rename ext4_block_zero_page_range() to ext4_block_zero_range()
ext4: factor out journalled block zeroing range
ext4: rename and extend ext4_block_truncate_page()
...
Merge tag 'for-linus-7.1-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs updates from Mike Marshall:
"Fixes:
- validate getxattr response length
- don't overflow the bufmap slot on readahead
- fix parsing problem with kernel debug keywords
Cleanup:
- take better advantage of strscpy
New:
- manage bufmap as folios
- add usercopy whitelist to orangefs_op_cache"
* tag 'for-linus-7.1-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
bufmap: manage as folios, V2.
orangefs: validate getxattr response length
orangefs_readahead: don't overflow the bufmap slot.
debugfs: take better advantage of strscpy.
orangefs: add usercopy whitelist to orangefs_op_cache
orangefs-debugfs.c: fix parsing problem with kernel debug keywords.
Merge tag 'ntfs-for-7.1-rc1-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs
Pull ntfs resurrection from Namjae Jeon:
"Ever since Kari Argillander’s 2022 report [1] regarding the state of
the ntfs3 driver, I have spent the last 4 years working to provide
full write support and current trends (iomap, no buffer head, folio),
enhanced performance, stable maintenance, utility support including
fsck for NTFS in Linux.
This new implementation is built upon the clean foundation of the
original read-only NTFS driver, adding:
- Write support:
Implemented full write support based on the classic read-only NTFS
driver. Added delayed allocation to improve write performance
through multi-cluster allocation and reduced fragmentation of the
cluster bitmap.
- iomap conversion:
Switched buffered IO (reads/writes), direct IO, file extent
mapping, readpages, and writepages to use iomap.
- Remove buffer_head:
Completely removed buffer_head usage by converting to folios. As a
result, the dependency on CONFIG_BUFFER_HEAD has been removed from
Kconfig.
- Stability improvements:
The new ntfs driver passes 326 xfstests, compared to 273 for ntfs3.
All tests passed by ntfs3 are a complete subset of the tests passed
by this implementation. Added support for fallocate, idmapped
mounts, permissions, and more.
Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Alexei Starovoitov:
"Most of the diff stat comes from Xu Kuohai's fix to emit ENDBR/BTI,
since all JITs had to be touched to move constant blinding out and
pass bpf_verifier_env in.
- Fix use-after-free in arena_vm_close on fork (Alexei Starovoitov)
- Dissociate struct_ops program with map if map_update fails (Amery
Hung)
- Fix out-of-range and off-by-one bugs in arm64 JIT (Daniel Borkmann)
- Fix precedence bug in convert_bpf_ld_abs alignment check (Daniel
Borkmann)
- Fix arg tracking for imprecise/multi-offset in BPF_ST/STX insns
(Eduard Zingerman)
- Copy token from main to subprogs to fix missing kallsyms (Eduard
Zingerman)
- Prevent double close and leak of btf objects in libbpf (Jiri Olsa)
- Fix af_unix null-ptr-deref in sockmap (Michal Luczaj)
- Fix NULL deref in map_kptr_match_type for scalar regs (Mykyta
Yatsenko)
- Avoid unnecessary IPIs. Remove redundant bpf_flush_icache() in
arm64 and riscv JITs (Puranjay Mohan)
- Fix out of bounds access. Validate node_id in arena_alloc_pages()
(Puranjay Mohan)
- Reject BPF-to-BPF calls and callbacks in arm32 JIT (Puranjay Mohan)
- Refactor all JITs to pass bpf_verifier_env to emit ENDBR/BTI for
indirect jump targets on x86-64, arm64 JITs (Xu Kuohai)
- Allow UTF-8 literals in bpf_bprintf_prepare() (Yihan Ding)"
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: (32 commits)
bpf, arm32: Reject BPF-to-BPF calls and callbacks in the JIT
bpf: Dissociate struct_ops program with map if map_update fails
bpf: Validate node_id in arena_alloc_pages()
libbpf: Prevent double close and leak of btf objects
selftests/bpf: cover UTF-8 trace_printk output
bpf: allow UTF-8 literals in bpf_bprintf_prepare()
selftests/bpf: Reject scalar store into kptr slot
bpf: Fix NULL deref in map_kptr_match_type for scalar regs
bpf: Fix precedence bug in convert_bpf_ld_abs alignment check
bpf, arm64: Emit BTI for indirect jump target
bpf, x86: Emit ENDBR for indirect jump targets
bpf: Add helper to detect indirect jump targets
bpf: Pass bpf_verifier_env to JIT
bpf: Move constants blinding out of arch-specific JITs
bpf, sockmap: Take state lock for af_unix iter
bpf, sockmap: Fix af_unix null-ptr-deref in proto update
selftests/bpf: Extend bpf_iter_unix to attempt deadlocking
bpf, sockmap: Fix af_unix iter deadlock
bpf, sockmap: Annotate af_unix sock:: Sk_state data-races
selftests/bpf: verify kallsyms entries for token-loaded subprograms
...
Merge tag 'cxl-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl
Pull CXL (Compute Express Link) updates from Dave Jiang:
"The significant change of interest is the handling of soft reserved
memory conflict between CXL and HMEM. In essence CXL will be the first
to claim the soft reserved memory ranges that belongs to CXL and
attempt to enumerate them with best effort. If CXL is not able to
enumerate the ranges it will punt them to HMEM.
There are also MAINTAINERS email changes from Dan Williams and
Jonathan Cameron"
* tag 'cxl-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (37 commits)
MAINTAINERS: Update Jonathan Cameron's email address
cxl/hdm: Add support for 32 switch decoders
MAINTAINERS: Update address for Dan Williams
tools/testing/cxl: Enable replay of user regions as auto regions
cxl/region: Add a region sysfs interface for region lock status
tools/testing/cxl: Test dax_hmem takeover of CXL regions
tools/testing/cxl: Simulate auto-assembly failure
dax/hmem: Parent dax_hmem devices
dax/hmem: Fix singleton confusion between dax_hmem_work and hmem devices
dax/hmem: Reduce visibility of dax_cxl coordination symbols
cxl/region: Constify cxl_region_resource_contains()
cxl/region: Limit visibility of cxl_region_contains_resource()
dax/cxl: Fix HMEM dependencies
cxl/region: Fix use-after-free from auto assembly failure
cxl/core: Check existence of cxl_memdev_state in poison test
cxl/core: use cleanup.h for devm_cxl_add_dax_region
cxl/core/region: move dax region device logic into region_dax.c
cxl/core/region: move pmem region driver logic into region_pmem.c
dax/hmem, cxl: Defer and resolve Soft Reserved ownership
cxl/region: Add helper to check Soft Reserved containment by CXL regions
...
Merge tag 'stop-machine.2026.04.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu
Pull stop-machine update from Paul McKenney:
- kernel-doc updates for stop_machine() and stop_machine_cpuslocked()
functions
* tag 'stop-machine.2026.04.16a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
stop_machine: Fix the documentation for a NULL cpus argument
Merge tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"There are two main changes, one feature removal, some code cleanup,
and a number of bug fixes.
Main changes:
- Detecting secure boot mode was limited to IMA. Make detecting
secure boot mode accessible to EVM and other LSMs
- IMA sigv3 support was limited to fsverity. Add IMA sigv3 support
for IMA regular file hashes and EVM portable signatures
Remove:
- Remove IMA support for asychronous hash calculation originally
added for hardware acceleration
Cleanup:
- Remove unnecessary Kconfig CONFIG_MODULE_SIG and CONFIG_KEXEC_SIG
tests
- Add descriptions of the IMA atomic flags
Bug fixes:
- Like IMA, properly limit EVM "fix" mode
- Define and call evm_fix_hmac() to update security.evm
- Fallback to using i_version to detect file change for filesystems
that do not support STATX_CHANGE_COOKIE
- Address missing kernel support for configured (new) TPM hash
algorithms
- Add missing crypto_shash_final() return value"
* tag 'integrity-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
evm: Enforce signatures version 3 with new EVM policy 'bit 3'
integrity: Allow sigv3 verification on EVM_XATTR_PORTABLE_DIGSIG
ima: add support to require IMA sigv3 signatures
ima: add regular file data hash signature version 3 support
ima: Define asymmetric_verify_v3() to verify IMA sigv3 signatures
ima: remove buggy support for asynchronous hashes
integrity: Eliminate weak definition of arch_get_secureboot()
ima: Add code comments to explain IMA iint cache atomic_flags
ima_fs: Correctly create securityfs files for unsupported hash algos
ima: check return value of crypto_shash_final() in boot aggregate
ima: Define and use a digest_size field in the ima_algo_desc structure
powerpc/ima: Drop unnecessary check for CONFIG_MODULE_SIG
ima: efi: Drop unnecessary check for CONFIG_MODULE_SIG/CONFIG_KEXEC_SIG
ima: fallback to using i_version to detect file change
evm: fix security.evm for a file with IMA signature
s390: Drop unnecessary CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
evm: Don't enable fix mode when secure boot is enabled
integrity: Make arch_ima_get_secureboot integrity-wide
Merge tag 'hwlock-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux
Pull hwspinlock updates from Bjorn Andersson:
"Remove the unused u8500 hardware spinlock driver, and clean out the
hwspinlock_pdata struct as this was the last user of the struct"
* tag 'hwlock-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux:
hwspinlock: remove now unused pdata from header file
hwspinlock: u8500: delete driver
Merge tag 'rpmsg-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux
Pull rpmsg updates from Bjorn Andersson:
"Mark 'data' argument in rpmsg_send() const, and perculate to related
drivers. Replace deprecated class_destroy() with class_unregister()"
* tag 'rpmsg-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux:
media: platform: mtk-mdp3: Constify buffer passed to mdp_vpu_sendmsg()
ASoC: qcom: Constify GPR packet being send over GPR interface
rpmsg: Constify buffer passed to send API
remoteproc: mtk_scp: Constify buffer passed to scp_send_ipi()
remoteproc: mtk_scp_ipi: Constify buffer passed to scp_ipi_send()
drivers: rpmsg: class_destroy() is deprecated
Merge tag 'rproc-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux
Pull remoteproc updates from Bjorn Andersson:
- Move requesting of IRQs in TI Keystone driver to probe time instead
of remoteproc start, to allow better handling of errors.
- Introduce support for more than 10 entries in the Qualcomm minidump
implementation.
- Add audio DSP remoteproc support for the Qualcomm Eliza platform. Add
modem remoteproc support for the Qualcomm MDM9607, MSM8917, MSM8937,
and MSM8940 platforms.
- Add list of Qualcomm QMI service ids to the QMI header file, in order
to avoid sprinkling them across the various drivers using them.
Migrate sysmon to use this constant.
- Fix several issues related to DeviceTree parsing and mailbox handling
in the Xilinx R5F remote processor driver.
- Fix incorrect error checks in reserved memory handling and polish the
code across i.MX and TI drivers.
* tag 'rproc-v7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux: (35 commits)
remoteproc: qcom: pas: Add Eliza ADSP support
dt-bindings: remoteproc: qcom,milos-pas: Document Eliza ADSP
remoteproc: qcom: Add missing space before closing bracket
dt-bindings: remoteproc: qcom: Drop types for firmware-name
remoteproc: qcom: Fix minidump out-of-bounds access on subsystems array
dt-bindings: remoteproc: k3-r5f: Add memory-region-names
dt-bindings: remoteproc: k3-r5f: Split up memory regions
remoteproc: use SIZE_MAX in rproc_u64_fit_in_size_t()
dt-bindings: remoteproc: qcom,sm8550-pas: Add Glymur CDSP
dt-bindings: remoteproc: qcom,sm8550-pas: Add Glymur ADSP
remoteproc: xlnx: Release mailbox channels on shutdown
remoteproc: sysmon: Use the unified QMI service ID instead of defining it locally
remoteproc: xlnx: Only access buffer information if IPI is buffered
remoteproc: xlnx: Avoid mailbox setup
remoteproc: keystone: Request IRQs in probe()
remoteproc: pru: Remove empty remove callback
remoteproc: pru: Use rproc_of_parse_firmware() to get firmware name
remoteproc: da8xx: Reorder resource fetching in probe()
remoteproc: da8xx: Remove unused local struct data
remoteproc: da8xx: Use dev_err_probe()
...
Merge tag 'for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pateldipen1984/linux
Pull hte updates from Dipen Patel:
- Add tegra264 HTE driver and dt binding support
- Remove tegra194 SoC Kconfig dependency
- Replace use of system_unbound_wq with system_dfl_wq
* tag 'for-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pateldipen1984/linux:
hte: tegra194: Add Tegra264 GTE support
dt-bindings: timestamp: Add Tegra264 support
hte: tegra194: remove Kconfig dependency on Tegra194 SoC
hte: replace use of system_unbound_wq with system_dfl_wq
Marco Crivellari [Mon, 23 Feb 2026 09:29:20 +0000 (10:29 +0100)]
block/blk-throttle: Add WQ_PERCPU to alloc_workqueue users
This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:
commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag")
The refactoring is going to alter the default behavior of
alloc_workqueue() to be unbound by default.
With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU. For more details see the Link tag below.
In order to keep alloc_workqueue() behavior identical, explicitly request
WQ_PERCPU.
Marco Crivellari [Mon, 23 Feb 2026 09:29:19 +0000 (10:29 +0100)]
block: Add WQ_PERCPU to alloc_workqueue users
This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:
commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq")
commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag")
The refactoring is going to alter the default behavior of
alloc_workqueue() to be unbound by default.
With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU. For more details see the Link tag below.
In order to keep alloc_workqueue() behavior identical, explicitly request
WQ_PERCPU.
Naman Jain [Fri, 10 Apr 2026 15:34:14 +0000 (15:34 +0000)]
block: relax pgmap check in bio_add_page for compatible zone device pages
bio_add_page() and bio_integrity_add_page() reject pages from different
dev_pagemaps entirely, returning 0 even when those pages have compatible
DMA mapping requirements. This forces callers to start a new bio when
buffers span pgmap boundaries, even though the pages could safely coexist
as separate bvec entries.
This matters for guests where memory is registered through
devm_memremap_pages() with MEMORY_DEVICE_GENERIC in multiple calls,
creating separate dev_pagemaps for each chunk. When a direct I/O buffer
spans two such chunks, bio_add_page() rejects the second page, forcing an
unnecessary bio split or I/O failure.
Introduce zone_device_pages_compatible() in blk.h to check whether two
pages can coexist in the same bio as separate bvec entries. The block DMA
iterator (blk_dma_map_iter_start) caches the P2PDMA mapping state from the
first segment and applies it to all others, so P2PDMA pages from different
pgmaps must not be mixed, and neither must P2PDMA and non-P2PDMA pages.
All other combinations (MEMORY_DEVICE_GENERIC pages from different pgmaps,
or MEMORY_DEVICE_GENERIC with normal RAM) use the same dma_map_phys path
and are safe.
Replace the blanket zone_device_pages_have_same_pgmap() rejection with
zone_device_pages_compatible(), while keeping
zone_device_pages_have_same_pgmap() as a merge guard.
Pages from different pgmaps can be added as separate bvec entries but
must not be coalesced into the same segment, as that would make
it impossible to recover the correct pgmap via page_pgmap().
Fixes: 49580e690755 ("block: add check when merging zone device pages") Cc: stable@vger.kernel.org Signed-off-by: Naman Jain <namjain@linux.microsoft.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://patch.msgid.link/20260410153414.4159050-3-namjain@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Naman Jain [Fri, 10 Apr 2026 15:34:13 +0000 (15:34 +0000)]
block: add pgmap check to biovec_phys_mergeable
biovec_phys_mergeable() is used by the request merge, DMA mapping,
and integrity merge paths to decide if two physically contiguous
bvec segments can be coalesced into one. It currently has no check
for whether the segments belong to different dev_pagemaps.
When zone device memory is registered in multiple chunks, each chunk
gets its own dev_pagemap. A single bio can legitimately contain
bvecs from different pgmaps -- iov_iter_extract_bvecs() breaks at
pgmap boundaries but the outer loop in bio_iov_iter_get_pages()
continues filling the same bio. If such bvecs are physically
contiguous, biovec_phys_mergeable() will coalesce them, making it
impossible to recover the correct pgmap for the merged segment
via page_pgmap().
Add a zone_device_pages_have_same_pgmap() check to prevent merging
bvec segments that span different pgmaps.
Fixes: 49580e690755 ("block: add check when merging zone device pages") Cc: stable@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Naman Jain <namjain@linux.microsoft.com> Link: https://patch.msgid.link/20260410153414.4159050-2-namjain@linux.microsoft.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
Guangshuo Li [Wed, 15 Apr 2026 14:57:08 +0000 (22:57 +0800)]
floppy: fix reference leak on platform_device_register() failure
When platform_device_register() fails in do_floppy_init(), the embedded
struct device in floppy_device[drive] has already been initialized by
device_initialize(), but the failure path jumps to out_remove_drives
without dropping the device reference for the current drive.
Previously registered floppy devices are cleaned up in out_remove_drives,
but the device for the drive that fails registration is not, leading to
a reference leak.
The issue was identified by a static analysis tool I developed and
confirmed by manual review. Fix this by calling put_device() for the
current floppy device before jumping to the common cleanup path.
Ming Lei [Wed, 15 Apr 2026 23:02:46 +0000 (07:02 +0800)]
ublk: use unchecked copy helpers for bio page data
Bio pages may originate from slab caches that lack a usercopy region
(e.g. jbd2 frozen metadata buffers allocated via jbd2_alloc()).
When CONFIG_HARDENED_USERCOPY is enabled, copy_to_iter() calls
check_copy_size() which rejects these slab pages, triggering a
kernel BUG in usercopy_abort().
This is a false positive: the data is ordinary block I/O content —
the same data the loop driver writes to its backing file via
vfs_iter_write(). The bvec length is always trusted, so the size
check in check_copy_size() is not needed either.
Switch to _copy_to_iter()/_copy_from_iter() which skip the
check_copy_size() wrapper while the underlying copy_to_user()
remains unchanged.
Acked-by: Caleb Sander Mateos <csander@purestorage.com> Fixes: 2299ceec364e ("ublk: use copy_{to,from}_iter() for user copy") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://patch.msgid.link/20260415230246.808176-1-tom.leiming@gmail.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
t10_pi_ref_tag() and ext_pi_ref_tag() are identical except for the final
truncation of the ref tag to 32 or 48 bits. Factor out a helper
full_pi_ref_tag() to return the untruncated ref tag and use it in
t10_pi_ref_tag() and ext_pi_ref_tag().
There is only a collection of bugfixes this time around, with no notable
changes to the core. Some of the more noteworthy bugfixes listed below.
- Enable die erase on MT35XU02GCBA. We knew this flash needed this fixup
since 7f77c561e227 ("mtd: spi-nor: micron-st: add TODO for fixing
mt35xu02gcba") but did not add it due to lack of hardware to test on.
- Fix locking on some Winbond w25q series flashes.
- Fix Auto Address Increment (AAI) writes on SST that flashes that start
on odd address. The write enable latch needs to be set again after the
single byte program.
drm/amdgpu: drop userq fence driver refs out of fence process()
amdgpu_userq_wait_ioctl() takes extra references on waited-on fence
drivers and stores them in waitq->fence_drv_xa. When a new userq fence is
created, those references are transferred into userq_fence->fence_drv_array
so they can be released when the fence completes.
However, those inherited references are currently only dropped from
amdgpu_userq_fence_driver_process(). If a fence never reaches that path,
such as it is already signaled when created, so we need to explicitly release
those fences in that case.
Cc: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Prike Liang <Prike.Liang@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: unpin and unref doorbell and wptr outside mutex
In amdgpu_userq_destroy once unmap_helpder is called within mutex
there is no need to hold mutex.
This helps in avoiding a deadlock between doorbell and wptr ww mutex
and we could unpin and unref these bos outside mutex safely.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: use pm_runtime_resume_and_get and fix err handling
Use pm_runtime_resume_and_get instead of pm_runtime_get_sync as it
return error but put the reference in the function itself.
In goto statements we need to drop the pm reference too.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: unmap_helper dont return the queue state
We check for return value of amdgpu_userq_unmap_helper and
compare it against the queue->state which is logically
wrong and we should just check for failure and do the needfull.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: unmap is to be called before freeing doorbell/wptr bo
Unmap the queue after freeing doorbell and wptr memory is completely
wrong. Any operation on the queue needs the doorbell and wptr to be
valid and hence fixing the ordering.
Also since we are using amdgpu_bo_reserve in non interruptrable mode
so there is no need to check for its return values.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: hold root bo lock in caller of input_va_validate
Caller should hold the reservation lock for root.bo in func
amdgpu_userq_input_va_validate.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: caller to take reserv lock for vas_list_cleanup
In function amdgpu_userq_buffer_vas_list_cleanup, remove the
reservation lock for vm and caller should make sure it's taken
before locking userq_mutex.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: create_mqd does not need userq_mutex
Reshuffle the code to run create_mqd outside the mutex.
code here is mostly setting up software structure init
before actually registering the userqueue in the xa and
to the driver.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: dont lock root bo with userq_mutex held
Do not hold reservation lock for root bo if userq_mutex
is already held in the call flow this cause a lock
issue with ttm_bo_delayed_delete.
Its better to lock the vm->root.bo first and then go ahead
with userq_mutex so userq_mutex threads dont get stuck until
the reservation lock is held.
In this case it helps in the function amdgpu_userq_buffer_vas_mapped
for each queue during restore_all.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: fix kerneldoc for amdgpu_userq_ensure_ev_fence
Move the comment for the caller to the definition for
amdgpu_userq_ensure_ev_fence in kerneldoc format.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: clean the VA mapping list for failed queue creation
If the queue creation failed during mapping of the important VA's
like queue_va, rptr_va and wptr_va. These needs to be cleaned
as queue destroy will not be called for such queues as user never
get call to creation failure.
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu/userq: avoid uneccessary locking in amdgpu_userq_create
Reorganise code to avoid holding mutex userq_mutex while
also trying to grab exec lock ww_mutex where its not needed
for function amdgpu_userq_input_va_validate
Signed-off-by: Sunil Khatri <sunil.khatri@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Fix ISM teardown crash from NULL dc dereference
The Idle State Manager (ISM) uses delayed work to apply display idle
optimizations later, instead of immediately. This helps avoid rapid idle
transitions that can hurt power or performance.
A crash was seen during driver teardown. The system boots normally and
the driver loads successfully. Later, when the GPU is being stopped, the
log shows:
GDB resolved dc_allow_idle_optimizations_internal+0xa6 to:
struct dc_state *context = dc->current_state;
The matching disassembly showed:
mov %rdi, %r12
mov 0x690(%r12), %r13
where r12 holds the dc pointer. A GDB layout dump of struct dc showed:
/* 1680 | 8 */ struct dc_state *current_state;
Since 1680 decimal is 0x690, this confirms that current_state is at
offset 0x690. The faulting access was effectively:
dc + 0x690
which indicates that dc was NULL at the time of dereference.
This shows that ISM work can still run during teardown after dc has
been cleared.
ISM is not expected to run after dc is destroyed. Fix this by disabling
ISM under dc_lock in amdgpu_dm_fini() before dc_destroy(), ensuring no
further ISM work runs after dc teardown.
Also add ASSERT(dm->dc) in amdgpu_dm_ism_commit_event() to enforce this
invariant, and ASSERT(mutex_is_locked(&dm->dc_lock)) in
amdgpu_dm_ism_disable() to clarify the locking requirement.
Fixes: 754003486c3c ("drm/amd/display: Add Idle state manager(ISM)") Suggested-by: Leo Li <sunpeng.li@amd.com> Cc: Ray Wu <ray.wu@amd.com> Cc: Roman Li <roman.li@amd.com> Cc: Alex Hung <alex.hung@amd.com> Cc: Tom Chung <chiahsuan.chung@amd.com> Cc: Harry Wentland <harry.wentland@amd.com> Cc: Aurabindo Pillai <aurabindo.pillai@amd.com> Cc: Mario Limonciello (AMD) <superm1@kernel.org> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com> Reviewed-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Move dml2_destroy to non-FPU compilation unit
On PREEMPT_RT kernels, vfree() can sleep because spin_lock is
converted to rt_mutex. dml2_destroy() calls vfree() while inside
an FPU-guarded region (preempt_count=2), which is illegal.
dml2_wrapper_fpu.c is compiled with CC_FLAGS_FPU which defines
_LINUX_FPU_COMPILATION_UNIT, making DC_RUN_WITH_PREEMPTION_ENABLED()
resolve to a no-op. This prevents the macro from cycling FPU
context off/on around vfree().
Move dml2_destroy() to dml2_wrapper.c (non-FPU compilation unit)
where DC_RUN_WITH_PREEMPTION_ENABLED() properly cycles DC_FP_END/
DC_FP_START around vfree(). This pairs it with dml2_allocate_memory()
which already lives there.
[How]
Add wrapper function to guard fpu properly for dcn21/dcn31/dcn315/dcn316.
Fixes: 3539437f354b ("drm/amd/display: Move FPU Guards From DML To DC - Part 1") Reviewed-by: Dillon Varone <dillon.varone@amd.com> Reviewed-by: Rafal Ostrowski <rafal.ostrowski@amd.com> Signed-off-by: Wayne Lin <Wayne.Lin@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amdgpu: Clear cached EDID pointer after drm_edid_free()
The driver stores EDID in amdgpu_connector->edid and uses it as a cache.
amdgpu_connector_get_edid() checks this pointer. If it is not NULL, it
assumes EDID is already present and does not read it again.
In some detect paths, the driver frees the EDID using drm_edid_free(),
but does not set the pointer to NULL. Because of this, the pointer still
looks valid even though the memory is already freed.
Later, when amdgpu_connector_get_edid() is called, it returns early and
does not read a new EDID. This can lead to using a freed pointer.
Fix this by setting amdgpu_connector->edid = NULL after drm_edid_free().
This makes sure the driver reads a fresh EDID and does not use invalid
memory.
Fixes: 71036457ad85 ("drm/amdgpu/amdgpu_connectors: remove amdgpu_connector_free_edid") Reported-by: Dan Carpenter <error27@gmail.com> Cc: Joshua Peisach <jpeisach@ubuntu.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com> Reviewed-by: Joshua Peisach <jpeisach@ubuntu.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
New:
- Add p-state schedule admissibility flags and frame-time utility
Fixes:
- Fixed incorrect math_mod() result due to wrong variable in fmod implementation (Cc: stable)
- Use overlay cursor when a color pipeline is active to avoid incorrect rendering
Cleanups:
- Add const qualifiers to watermark params struct
- Fix narrowing-conversion compiler warnings
Signed-off-by: Taimur Hassan <Syed.Hassan@amd.com> Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Reviewed-by: Alex Hung <alex.hung@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Wenjing Liu [Thu, 26 Mar 2026 21:39:28 +0000 (17:39 -0400)]
drm/amd/display: add pstate schedule admissibility flags and frame-time utility
[Why]
Core needs to track pstate schedule admissibility for different global
change scenarios (fclk, temp read, PPT) and requires a reusable way to compute
per-stream frame time from timing parameters.
[How]
Extend dml2_core_internal_mode_support_info with:
fclk_pstate_schedule_admissible
temp_read_pstate_schedule_admissible
ppt_pstate_schedule_admissible
Add dummy_double_array[3][DML2_MAX_PLANES] to
dml2_core_calcs_mode_support_locals.
Introduce dml2_core_utils_get_frame_time_us() in dml2_core_utils.c and export
it in dml2_core_utils.h to compute frame time in microseconds from stream
timing (vline time * (vactive + vblank)).
Reviewed-by: Dillon Varone <dillon.varone@amd.com> Signed-off-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Alex Hung [Wed, 25 Mar 2026 02:03:25 +0000 (20:03 -0600)]
drm/amd/display: Use overlay cursor when color pipeline is active
Force overlay cursor mode when an underlying plane has a non-bypassed
color pipeline to avoid incorrect cursor transformation.
Reviewed-by: Sun peng (Leo) Li <sunpeng.li@amd.com> Signed-off-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why] Implicit conversions from wider integer types to byte-sized fields
were generating compiler warnings. These warnings hide intentional protocol
/storage boundaries and reduce signal quality during builds. Making
conversion intent explicit improves readability and warning hygiene
without changing behavior.
[How] Added explicit, type-safe casts at intentional narrow-storage
boundaries. Kept data models & runtime logic unchanged, only clarifying
conversion intent.
Functionality and behavior is unchanged; only type intent is explicit.
Aligned warning cleanup with existing coding standards for explicit
boundary conversions.
Reviewed-by: Aric Cyr <aric.cyr@amd.com> Signed-off-by: Gaghik Khachatrian <gaghik.khachatrian@amd.com> Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Ray Wu [Tue, 7 Apr 2026 08:24:39 +0000 (16:24 +0800)]
drm/amd/display: fix NULL ptr deref in ISM delayed work
dc_destroy() sets dm->dc to NULL before amdgpu_dm_ism_fini() is called,
leaving a window where in-flight ISM delayed work dereferences the stale
pointer. Call amdgpu_dm_ism_fini() in amdgpu_dm_fini() before dc_destroy().
Fixes: 754003486c3c ("drm/amd/display: Add Idle state manager(ISM)") Reviewed-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Ray Wu <ray.wu@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Add missing description for do_mccs parameter in
amdgpu_dm_update_freesync_caps.
Fixes the below with gcc W=1:
../display/amdgpu_dm/amdgpu_dm.c:13269 function parameter 'do_mccs' not described in 'amdgpu_dm_update_freesync_caps'
Fixes: 8dc88c6a5948 ("drm/amd/display: Avoid to do MCCS transaction if unnecessary") Cc: Harry Wentland <harry.wentland@amd.com> Cc: Wayne Lin <Wayne.Lin@amd.com> Cc: Roman Li <roman.li@amd.com> Cc: Alex Hung <alex.hung@amd.com> Cc: Tom Chung <chiahsuan.chung@amd.com> Cc: Aurabindo Pillai <aurabindo.pillai@amd.com> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com> Reviewed-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Roman Li [Thu, 9 Apr 2026 17:37:36 +0000 (13:37 -0400)]
drm/amd/display: Remove redundant includes from DC
[Why]
The explicit include of linux/array_size.h in Display Core (DC) is
redundant. The ARRAY_SIZE macro is already provided by dm_services.h
(via os_types.h) which DC includes.
[How]
Remove the unnecessary #include <linux/array_size.h> from
dc_hw_sequencer.c and dce_clock_source.c.
Fixes: 2d2366176445 ("drm/amd/display: Replace inline NUM_ELEMENTS macro with ARRAY_SIZE") CC: Linus Probert <linus.probert@gmail.com> Signed-off-by: Roman Li <Roman.Li@amd.com> Reviewed-by: Alex Hung <alex.hung@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Taimur Hassan [Fri, 27 Mar 2026 23:54:22 +0000 (18:54 -0500)]
drm/amd/display: Promote DC to 3.2.377
This version brings along the following updates:
- Enable sink freesync via MCCS with pcon whitelist adjustments
- Rework YCbCr422 DSC policy
- Update DML2.1 parameters
- Fix coding style issues and compiler warnings
Reviewed-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Taimur Hassan <Syed.Hassan@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Chuanyu Tseng [Sat, 28 Mar 2026 00:13:49 +0000 (08:13 +0800)]
drm/amd/display: Fix coding style issue
[Why & How]
Function logic should put after variable declare section, so let's move it.
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com> Signed-off-by: Chuanyu Tseng <Chuanyu.Tseng@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why/How]
UrgLatency value is passed in twice to the prefetch calculations.
Once through the UrgentLatency term and once through the Turg term.
Only Turg is used in the prefetch calculation so remove the unused UrgentLatency parameter
Reviewed-by: Dillon Varone <dillon.varone@amd.com> Signed-off-by: Zheng, Austin <Austin.Zheng@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
The MinTTU policy in DML2.1 does not guarantee that we support p-state
in blank. This is a delta vs dml2 and earlier revisions as the prefetch
mode override has been removed in favor of a more configurable pstate
optimizer.
[How]
Split off DCN42 with its own PMO helpers so that we can use a simpler
strategy of only allowing the mode if we support p-state in vblank and
if vactive has enough latency hiding.
The actual hookup to use these helpers in the PMO factory will be
done in a later patch to satisfy build system requirements.
Reviewed-by: Dillon Varone <dillon.varone@amd.com> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: move memory latency update to dml for dcn42
Memory latencies are soc specific and should be part of dml soc
bounding box. This change removes them from clk_mgr and has
latency update happen based on memory type when dml socbb is being
updated.
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Reviewed-by: Charlene Liu <charlene.liu@amd.com> Signed-off-by: Dmytro Laktyushkin <dmytro.laktyushkin@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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