Merge tag 'slab-for-6.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab updates from Vlastimil Babka:

 - Add new slab_strict_numa boot parameter to enforce per-object memory
   policies on top of slab folio policies, for systems where saving cost
   of remote accesses is more important than minimizing slab allocation
   overhead (Christoph Lameter)

 - Fix for freeptr_offset alignment check being too strict for m68k
   (Geert Uytterhoeven)

 - krealloc() fixes for not violating __GFP_ZERO guarantees on
   krealloc() when slub_debug (redzone and object tracking) is enabled
   (Feng Tang)

 - Fix a memory leak in case sysfs registration fails for a slab cache,
   and also no longer fail to create the cache in that case (Hyeonggon
   Yoo)

 - Fix handling of detected consistency problems (due to buggy slab
   user) with slub_debug enabled, so that it does not cause further list
   corruption bugs (yuan.gao)

 - Code cleanup and kerneldocs polishing (Zhen Lei, Vlastimil Babka)

* tag 'slab-for-6.13-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  slab: Fix too strict alignment check in create_cache()
  mm/slab: Allow cache creation to proceed even if sysfs registration fails
  mm/slub: Avoid list corruption when removing a slab from the full list
  mm/slub, kunit: Add testcase for krealloc redzone and zeroing
  mm/slub: Improve redzone check and zeroing for krealloc()
  mm/slub: Consider kfence case for get_orig_size()
  SLUB: Add support for per object memory policies
  mm, slab: add kerneldocs for common SLAB_ flags
  mm/slab: remove duplicate check in create_cache()
  mm/slub: Move krealloc() and related code to slub.c
  mm/kasan: Don't store metadata inside kmalloc object when slub_debug_orig_size is on

2 files changed, 19 insertions, 0 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a4736ee87b1a..062ea4adb51d 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -6158,6 +6158,16 @@
 			For more information see Documentation/mm/slub.rst.
 			(slub_nomerge legacy name also accepted for now)
 
+	slab_strict_numa	[MM]
+			Support memory policies on a per object level
+			in the slab allocator. The default is for memory
+			policies to be applied at the folio level when
+			a new folio is needed or a partial folio is
+			retrieved from the lists. Increases overhead
+			in the slab fastpaths but gains more accurate
+			NUMA kernel object placement which helps with slow
+			interconnects in NUMA systems.
+
 	slram=		[HW,MTD]
 
 	smart2=		[HW]
diff --git a/Documentation/mm/slub.rst b/Documentation/mm/slub.rst
index 60d350d08362..84ca1dc94e5e 100644
--- a/Documentation/mm/slub.rst
+++ b/Documentation/mm/slub.rst
@@ -175,6 +175,15 @@ can be influenced by kernel parameters:
 	``slab_max_order`` to 0, what cause minimum possible order of
 	slabs allocation.
 
+``slab_strict_numa``
+        Enables the application of memory policies on each
+        allocation. This results in more accurate placement of
+        objects which may result in the reduction of accesses
+        to remote nodes. The default is to only apply memory
+        policies at the folio level when a new folio is acquired
+        or a folio is retrieved from the lists. Enabling this
+        option reduces the fastpath performance of the slab allocator.
+
 SLUB Debug output
 =================