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.
drm/bridge: waveshare-dsi: support DSI LCD kits with LVDS panels
Several Waveshare DSI LCD kits use LVDS panels and the ICN6202 DSI2LVDS
bridge. Support that setup by handling waveshare,dsi2lvds compatible.
The only difference with the existing waveshare,dsi2dpi is the bridge's
output type (LVDS vs DPI).
Several the Waveshare DSI LCD panel kits use DSI2LVDS ICN6202 bridge
together with the LVDS panels. Define new compatible for the on-kit
bridge setup (it is not itmized and it uses Waveshare prefix since the
rest of the integration details are not known).
Note: the ICN6202 / ICN6211 bridges are completely handled by the board
itself, they should not be programmed by the host (which otherwise might
override correct params), etc. As such, it doesn't make sense to use
those in the compat strings. I consider those to be an internal detail
of the setup.
Add devm_drm_panel_add(), devres-managed version of drm_panel_add().
It's not uncommon for the panel drivers to use devres functions for most
of the resources. Provide corresponding replacement for drm_panel_add().
drm/panel: jadard-jd9365da-h3: set prepare_prev_first
Sending DSI commands from the prepare() callback requires DSI link to be
up at that point. For DSI hosts is guaranteed only if the panel driver
sets the .prepare_prev_first flag. Set it to let these panels work with
the DSI hosts which don't power on the link in their .mode_set callback.
drm/panel: jadard-jd9365da-h3: support variable DSI configuration
Several panels support attachment either using 4 DSI lanes or just 2. In
some cases, this requires a different panel mode to fulfill clock
requirements. Extend the driver to handle such cases by letting the
panel description to omit lanes specification and parsing number of
lanes from the DT.
Sending DSI commands from the prepare() callback requires DSI link to be
up at that point. For DSI hosts is guaranteed only if the panel driver
sets the .prepare_prev_first flag. Set it to let these panels work with
the DSI hosts which don't power on the link in their .mode_set callback.
drm/panel: himax-hx83102: support Waveshare 12.3" DSI panel
Add support for the Waveshare 12.3" DSI TOUCH-A panel. According to the
vendor driver, it uses different mode_flags, so let the panel
descriptions override driver-wide defaults.
drm/of: add helper to count data-lanes on a remote endpoint
If the DSI panel supports versatile lanes configuration, its driver
might require determining the number of DSI data lanes, which is usually
specified on the DSI host side of the OF graph. Add new helper as a
pair to drm_of_get_data_lanes_count_ep() that lets callers determine
number of data-lanes on the remote side of the OF graph.
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/radeon: fix memory leak in radeon_ring_restore() on lock failure
radeon_ring_restore() takes ownership of the data buffer allocated by
radeon_ring_backup(). The caller (radeon_gpu_reset()) only frees it in
the non-restore branch; in the restore branch it relies on
radeon_ring_restore() to free it.
If radeon_ring_lock() fails, the function returned early without calling
kvfree(data), leaking the ring backup buffer on every GPU reset that
fails at the lock stage. During repeated GPU resets this causes
cumulative kernel memory exhaustion.
Free data before returning the error.
Fixes: 55d7c22192be ("drm/radeon: implement ring saving on reset v4") Signed-off-by: Yuho Choi <dbgh9129@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Werner Kasselman [Wed, 15 Apr 2026 22:13:52 +0000 (22:13 +0000)]
drm/radeon: fix integer overflow in radeon_align_pitch()
radeon_align_pitch() has the same kind of overflow issue as the old
amdgpu helper: both the alignment round-up add and the final
'aligned * cpp' calculation can overflow signed int.
If that wraps, radeon_mode_dumb_create() can end up returning an
invalid pitch or creating a zero-sized dumb buffer.
Fix this by using check_add_overflow() for the alignment round-up and
check_mul_overflow() for the final pitch calculation, returning 0 on
overflow. Also reject zero pitch and size in
radeon_mode_dumb_create().
Found via AST-based call-graph analysis using sqry.
Fixes: ff72145badb8 ("drm: dumb scanout create/mmap for intel/radeon (v3)") Signed-off-by: Werner Kasselman <werner@verivus.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
- Add allow_clock_gating to dcn42 dccg.
- Bypass post csc for additional color spaces in dcn42.
- Remove unused dml2_project.
- Unset Replay desync error verification by default.
- Align HWSS fast commit path with legacy path.
- Fix implicit narrowing conversion warnings.
- Fix double free.
- Introduce power module on Linux.
- Add power module on Linux.
- Fix fpu guard warning.
- Add Replay/PSR active check in link loss status check.
- Remove SYMCLK F and G values from link encoder and MANUAL_FLOW_CONTROL from optc.
- Add minimum vfp requirement.
- Fix narrowing boundaries and eDP parser assignment.
- Fix dml2_0 narrowing boundaries.
- Add README.md file to DML2_0 repository.
- Fix DPMS using partially updated pipe context.
- Move dml2_destroy to non-FPU compilation unit.
Signed-off-by: Taimur Hassan <Syed.Hassan@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Acked-by: Tom Chung <ChiaHsuan.Chung@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Fix DPMS using partially updated pipe context
[Why & How]
DPMS functions should not use partially updated pipe context passed
as argument of commit_planes_do_stream_update, and instead use the
one in current_state, which is guaranteed to be the most recently
programmed HW config.
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Dominik Kaszewski <dominik.kaszewski@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why] drm/amd/display dml2_0 code had implicit narrowing conversions reported by
a warning in timing, watermark, and translation paths.
[How] Apply explicit boundary casts for intentional narrowing, preserve wider
intermediate math, and use wider timing intermediates where required for safe
range handling.
drm/amd/display: Fix narrowing boundaries and eDP parser assignment
[Why] drm/amd/display had implicit integer narrowing at protocol/storage boundaries
and an incomplete eDP assignment in integrated info parsing.
[How] Apply explicit boundary casts for intentional narrowing, keep intermediate math
in wider types, and restore explicit eDP field mapping in v2.2 parser.
[WHY&HOW]
Vertical front porch (vfp) must be greater than 1, and must be patched
if it isn't. This must be done pre-DML so the DLG programming remains
consistent with the OTG programming.
Allen Li [Tue, 10 Mar 2026 08:49:08 +0000 (16:49 +0800)]
drm/amd/display: Add Replay/PSR active check in link loss status check
[Why&How]
To avoid unnecessary link retraining when the panel is in Replay/PSR mode,
we need to check if it's in active state and ESD information before we
decide to retrain the link.
Reviewed-by: ChunTao Tso <chuntao.tso@amd.com> Signed-off-by: Allen Li <allen.li@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Ray Wu [Tue, 30 Dec 2025 01:56:28 +0000 (09:56 +0800)]
drm/amd/display: Add power module on Linux
[Why & How]
Refactors dm to utilize the power module for managing
replay, PSR, and backlight control functionalities.
Key changes:
- Introduced replay / PSR events to enable / disable replay / PSR.
- Implemented replay rate control and power option
- Refactored backlight control by using the power module.
- Enhanced handling of VRR within replay and PSR logic.
Reviewed-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Ray Wu <ray.wu@amd.com> Signed-off-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Ray Wu [Fri, 27 Feb 2026 21:09:19 +0000 (16:09 -0500)]
drm/amd/display: Introduce power module on Linux
[Why]
Other OS supported by DC uses the power module to manage panel power
features such as backlight and self-refresh. It contains enhancements
on top what amdgpu_dm is doing today that can benefit power.
[How]
Introduce the power module. It's currently not being used anywhere, a
future change will incorporate it into amdgpu_dm.
Reviewed-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Ray Wu <ray.wu@amd.com> Signed-off-by: Leo Li <sunpeng.li@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
[Why]
Multiple display source files contain implicit narrowing
conversions when assigning wider integer types (int, uint32_t)
to narrower fields (uint8_t, uint16_t) at hardware register,
protocol, and storage boundaries. These conversions are
intentional but undocumented, and accompanying runtime assertions
add noise without providing compile-time safety.
[How]
Add explicit casts at all intentional narrowing boundaries across
display source files. Use narrower loop variable types where loop
bounds guarantee safe range. Remove runtime assertions paired
with narrowing casts, inline single-use intermediate variables,
and revert block scopes and braces introduced solely to contain
those assertions.
Rafal Ostrowski [Fri, 13 Mar 2026 10:39:10 +0000 (11:39 +0100)]
drm/amd/display: Align HWSS fast commit path with legacy path
Add missing operations to commit_planes_for_stream_fast and
hwss_build_fast_sequence to match the legacy commit_planes_for_stream
behavior for UPDATE_TYPE_FAST updates.
- Add stream-level fast update flags (cursor_attr, cursor_pos,
periodic_interrupt, info_frame, dmdata, dither) to dc_stream.h
- Add stream-level fields to dc_fast_update struct for fast/full
update classification in populate_fast_updates/fast_updates_exist
- Add HWSS_SETUP_PERIODIC_INTERRUPT block sequence entry, delegating
to dc->hwss.setup_periodic_interrupt instead of calling dcn10
directly
- Add HUBP_ENABLE_3DLUT_FL block for 3DLUT FL with
should_update_pipe_for_stream/plane guards
- Add DPP_SET_CURSOR_MATRIX block with new cursor_csc_change flag
- Widen DPP_PROGRAM_GAMUT_REMAP to also trigger on stream gamut_remap
- Add info frame, dmdata, dither, and cursor blocks to
hwss_build_fast_sequence
- Reclassify cursor_position/cursor_attributes as UPDATE_TYPE_FAST
- Extract dc_dmdata_types.h to resolve circular include between
hw_sequencer.h and dc_stream.h
- Remove dcn10_hwseq.h include from dc_hw_sequencer.c
Reviewed-by: Alvin Lee <alvin.lee2@amd.com> Signed-off-by: Rafal Ostrowski <rafal.ostrowski@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Allen Li [Mon, 16 Mar 2026 11:32:19 +0000 (19:32 +0800)]
drm/amd/display: Unset Replay desync error verification by default
[Why & How]
There will be an unexpected desync error while doing PSR -> Replay transit,
so we want to disable the replay desync error detection by default.
Reviewed-by: Robin Chen <robin.chen@amd.com> Signed-off-by: Allen Li <allen.li@amd.com> Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>