The quilt patch titled
Subject: mm/slab: introduce SLAB_NO_OBJ_EXT to avoid obj_ext creation
has been removed from the -mm tree. Its filename was
mm-slab-introduce-slab_no_obj_ext-to-avoid-obj_ext-creation.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Subject: mm/slab: introduce SLAB_NO_OBJ_EXT to avoid obj_ext creation
Date: Thu, 21 Mar 2024 09:36:30 -0700
Slab extension objects can't be allocated before slab infrastructure is
initialized. Some caches, like kmem_cache and kmem_cache_node, are
created before slab infrastructure is initialized. Objects from these
caches can't have extension objects. Introduce SLAB_NO_OBJ_EXT slab flag
to mark these caches and avoid creating extensions for objects allocated
from these slabs.
Link: https://lkml.kernel.org/r/20240321163705.3067592-9-surenb@xxxxxxxxxx
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>
Reviewed-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
Reviewed-by: Vlastimil Babka <vbabka@xxxxxxx>
Tested-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Alex Gaynor <alex.gaynor@xxxxxxxxx>
Cc: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Cc: Andreas Hindborg <a.hindborg@xxxxxxxxxxx>
Cc: Benno Lossin <benno.lossin@xxxxxxxxx>
Cc: "Björn Roy Baron" <bjorn3_gh@xxxxxxxxxxxxxx>
Cc: Boqun Feng <boqun.feng@xxxxxxxxx>
Cc: Christoph Lameter <cl@xxxxxxxxx>
Cc: Dennis Zhou <dennis@xxxxxxxxxx>
Cc: Gary Guo <gary@xxxxxxxxxxx>
Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: Miguel Ojeda <ojeda@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: Wedson Almeida Filho <wedsonaf@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/slab.h | 10 ++++++++++
mm/slub.c | 5 +++--
2 files changed, 13 insertions(+), 2 deletions(-)
--- a/include/linux/slab.h~mm-slab-introduce-slab_no_obj_ext-to-avoid-obj_ext-creation
+++ a/include/linux/slab.h
@@ -56,6 +56,9 @@ enum _slab_flag_bits {
#endif
_SLAB_OBJECT_POISON,
_SLAB_CMPXCHG_DOUBLE,
+#ifdef CONFIG_SLAB_OBJ_EXT
+ _SLAB_NO_OBJ_EXT,
+#endif
_SLAB_FLAGS_LAST_BIT
};
@@ -202,6 +205,13 @@ enum _slab_flag_bits {
#endif
#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */
+/* Slab created using create_boot_cache */
+#ifdef CONFIG_SLAB_OBJ_EXT
+#define SLAB_NO_OBJ_EXT __SLAB_FLAG_BIT(_SLAB_NO_OBJ_EXT)
+#else
+#define SLAB_NO_OBJ_EXT __SLAB_FLAG_UNUSED
+#endif
+
/*
* ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
*
--- a/mm/slub.c~mm-slab-introduce-slab_no_obj_ext-to-avoid-obj_ext-creation
+++ a/mm/slub.c
@@ -5693,7 +5693,8 @@ void __init kmem_cache_init(void)
node_set(node, slab_nodes);
create_boot_cache(kmem_cache_node, "kmem_cache_node",
- sizeof(struct kmem_cache_node), SLAB_HWCACHE_ALIGN, 0, 0);
+ sizeof(struct kmem_cache_node),
+ SLAB_HWCACHE_ALIGN | SLAB_NO_OBJ_EXT, 0, 0);
hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
@@ -5703,7 +5704,7 @@ void __init kmem_cache_init(void)
create_boot_cache(kmem_cache, "kmem_cache",
offsetof(struct kmem_cache, node) +
nr_node_ids * sizeof(struct kmem_cache_node *),
- SLAB_HWCACHE_ALIGN, 0, 0);
+ SLAB_HWCACHE_ALIGN | SLAB_NO_OBJ_EXT, 0, 0);
kmem_cache = bootstrap(&boot_kmem_cache);
kmem_cache_node = bootstrap(&boot_kmem_cache_node);
_
Patches currently in -mm which might be from surenb@xxxxxxxxxx are
userfaultfd-remove-write_once-when-setting-folio-index-during-uffdio_move.patch
