6.11-stable patches

added patches:
	revert-mm-introduce-pf_memalloc_noreclaim-pf_memalloc_nowarn.patch
	series

diff --git a/queue-6.11/revert-mm-introduce-pf_memalloc_noreclaim-pf_memalloc_nowarn.patch b/queue-6.11/revert-mm-introduce-pf_memalloc_noreclaim-pf_memalloc_nowarn.patch
new file mode 100644 (file)
index 0000000..cd11fc2
--- /dev/null
+++ b/queue-6.11/revert-mm-introduce-pf_memalloc_noreclaim-pf_memalloc_nowarn.patch
@@ -0,0 +1,92 @@
+From 9a8da05d7ad619beb84d0c6904c3fa7022c6fb9b Mon Sep 17 00:00:00 2001
+From: Michal Hocko <mhocko@suse.com>
+Date: Thu, 26 Sep 2024 19:11:51 +0200
+Subject: Revert "mm: introduce PF_MEMALLOC_NORECLAIM, PF_MEMALLOC_NOWARN"
+
+From: Michal Hocko <mhocko@suse.com>
+
+commit 9a8da05d7ad619beb84d0c6904c3fa7022c6fb9b upstream.
+
+This reverts commit eab0af905bfc3e9c05da2ca163d76a1513159aa4.
+
+There is no existing user of those flags.  PF_MEMALLOC_NOWARN is dangerous
+because a nested allocation context can use GFP_NOFAIL which could cause
+unexpected failure.  Such a code would be hard to maintain because it
+could be deeper in the call chain.
+
+PF_MEMALLOC_NORECLAIM has been added even when it was pointed out [1] that
+such a allocation contex is inherently unsafe if the context doesn't fully
+control all allocations called from this context.
+
+While PF_MEMALLOC_NOWARN is not dangerous the way PF_MEMALLOC_NORECLAIM is
+it doesn't have any user and as Matthew has pointed out we are running out
+of those flags so better reclaim it without any real users.
+
+[1] https://lore.kernel.org/all/ZcM0xtlKbAOFjv5n@tiehlicka/
+
+Link: https://lkml.kernel.org/r/20240926172940.167084-3-mhocko@kernel.org
+Signed-off-by: Michal Hocko <mhocko@suse.com>
+Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
+Reviewed-by: Christoph Hellwig <hch@lst.de>
+Reviewed-by: Dave Chinner <dchinner@redhat.com>
+Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
+Cc: Al Viro <viro@zeniv.linux.org.uk>
+Cc: Christian Brauner <brauner@kernel.org>
+Cc: James Morris <jmorris@namei.org>
+Cc: Jan Kara <jack@suse.cz>
+Cc: Kent Overstreet <kent.overstreet@linux.dev>
+Cc: Paul Moore <paul@paul-moore.com>
+Cc: Serge E. Hallyn <serge@hallyn.com>
+Cc: Yafang Shao <laoar.shao@gmail.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/sched.h    |    4 ++--
+ include/linux/sched/mm.h |   17 ++++-------------
+ 2 files changed, 6 insertions(+), 15 deletions(-)
+
+--- a/include/linux/sched.h
++++ b/include/linux/sched.h
+@@ -1659,8 +1659,8 @@ extern struct pid *cad_pid;
+                                                * I am cleaning dirty pages from some other bdi. */
+ #define PF_KTHREAD            0x00200000      /* I am a kernel thread */
+ #define PF_RANDOMIZE          0x00400000      /* Randomize virtual address space */
+-#define PF_MEMALLOC_NORECLAIM 0x00800000      /* All allocation requests will clear __GFP_DIRECT_RECLAIM */
+-#define PF_MEMALLOC_NOWARN    0x01000000      /* All allocation requests will inherit __GFP_NOWARN */
++#define PF__HOLE__00800000    0x00800000
++#define PF__HOLE__01000000    0x01000000
+ #define PF__HOLE__02000000    0x02000000
+ #define PF_NO_SETAFFINITY     0x04000000      /* Userland is not allowed to meddle with cpus_mask */
+ #define PF_MCE_EARLY          0x08000000      /* Early kill for mce process policy */
+--- a/include/linux/sched/mm.h
++++ b/include/linux/sched/mm.h
+@@ -258,25 +258,16 @@ static inline gfp_t current_gfp_context(
+ {
+       unsigned int pflags = READ_ONCE(current->flags);
+ 
+-      if (unlikely(pflags & (PF_MEMALLOC_NOIO |
+-                             PF_MEMALLOC_NOFS |
+-                             PF_MEMALLOC_NORECLAIM |
+-                             PF_MEMALLOC_NOWARN |
+-                             PF_MEMALLOC_PIN))) {
++      if (unlikely(pflags & (PF_MEMALLOC_NOIO | PF_MEMALLOC_NOFS | PF_MEMALLOC_PIN))) {
+               /*
+-               * Stronger flags before weaker flags:
+-               * NORECLAIM implies NOIO, which in turn implies NOFS
++               * NOIO implies both NOIO and NOFS and it is a weaker context
++               * so always make sure it makes precedence
+                */
+-              if (pflags & PF_MEMALLOC_NORECLAIM)
+-                      flags &= ~__GFP_DIRECT_RECLAIM;
+-              else if (pflags & PF_MEMALLOC_NOIO)
++              if (pflags & PF_MEMALLOC_NOIO)
+                       flags &= ~(__GFP_IO | __GFP_FS);
+               else if (pflags & PF_MEMALLOC_NOFS)
+                       flags &= ~__GFP_FS;
+ 
+-              if (pflags & PF_MEMALLOC_NOWARN)
+-                      flags |= __GFP_NOWARN;
+-
+               if (pflags & PF_MEMALLOC_PIN)
+                       flags &= ~__GFP_MOVABLE;
+       }

diff --git a/queue-6.11/series b/queue-6.11/series
new file mode 100644 (file)
index 0000000..ce7a3cc
--- /dev/null
+++ b/queue-6.11/series
@@ -0,0 +1 @@
+revert-mm-introduce-pf_memalloc_noreclaim-pf_memalloc_nowarn.patch