Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'slab-for-6.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab fixes from Vlastimil Babka:
- Stable fix to make slub_debug code not access invalid pointers in the
process of reporting issues (Li Qiong)
- Stable fix to make object tracking pass gfp flags to stackdepot to
avoid deadlock in contexts that can't even wake up kswapd due to e.g.
timers debugging enabled (yangshiguang)
* tag 'slab-for-6.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
mm: slub: avoid wake up kswapd in set_track_prepare
mm/slub: avoid accessing metadata when pointer is invalid in object_err()
+26
-11
+26
-11
mm/slub.c
+26
-11
mm/slub.c
···
962
962
}
963
963
964
964
#ifdef CONFIG_STACKDEPOT
965
-
static noinline depot_stack_handle_t set_track_prepare(void)
965
+
static noinline depot_stack_handle_t set_track_prepare(gfp_t gfp_flags)
966
966
{
967
967
depot_stack_handle_t handle;
968
968
unsigned long entries[TRACK_ADDRS_COUNT];
969
969
unsigned int nr_entries;
970
970
971
971
nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3);
972
-
handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT);
972
+
handle = stack_depot_save(entries, nr_entries, gfp_flags);
973
973
974
974
return handle;
975
975
}
976
976
#else
977
-
static inline depot_stack_handle_t set_track_prepare(void)
977
+
static inline depot_stack_handle_t set_track_prepare(gfp_t gfp_flags)
978
978
{
979
979
return 0;
980
980
}
···
996
996
}
997
997
998
998
static __always_inline void set_track(struct kmem_cache *s, void *object,
999
-
enum track_item alloc, unsigned long addr)
999
+
enum track_item alloc, unsigned long addr, gfp_t gfp_flags)
1000
1000
{
1001
-
depot_stack_handle_t handle = set_track_prepare();
1001
+
depot_stack_handle_t handle = set_track_prepare(gfp_flags);
1002
1002
1003
1003
set_track_update(s, object, alloc, addr, handle);
1004
1004
}
···
1140
1140
return;
1141
1141
1142
1142
slab_bug(s, reason);
1143
-
print_trailer(s, slab, object);
1143
+
if (!object || !check_valid_pointer(s, slab, object)) {
1144
+
print_slab_info(slab);
1145
+
pr_err("Invalid pointer 0x%p\n", object);
1146
+
} else {
1147
+
print_trailer(s, slab, object);
1148
+
}
1144
1149
add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
1145
1150
1146
1151
WARN_ON(1);
···
1926
1921
static inline void slab_pad_check(struct kmem_cache *s, struct slab *slab) {}
1927
1922
static inline int check_object(struct kmem_cache *s, struct slab *slab,
1928
1923
void *object, u8 val) { return 1; }
1929
-
static inline depot_stack_handle_t set_track_prepare(void) { return 0; }
1924
+
static inline depot_stack_handle_t set_track_prepare(gfp_t gfp_flags) { return 0; }
1930
1925
static inline void set_track(struct kmem_cache *s, void *object,
1931
-
enum track_item alloc, unsigned long addr) {}
1926
+
enum track_item alloc, unsigned long addr, gfp_t gfp_flags) {}
1932
1927
static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n,
1933
1928
struct slab *slab) {}
1934
1929
static inline void remove_full(struct kmem_cache *s, struct kmem_cache_node *n,
···
3881
3876
* For debug caches here we had to go through
3882
3877
* alloc_single_from_partial() so just store the
3883
3878
* tracking info and return the object.
3879
+
*
3880
+
* Due to disabled preemption we need to disallow
3881
+
* blocking. The flags are further adjusted by
3882
+
* gfp_nested_mask() in stack_depot itself.
3884
3883
*/
3885
3884
if (s->flags & SLAB_STORE_USER)
3886
-
set_track(s, freelist, TRACK_ALLOC, addr);
3885
+
set_track(s, freelist, TRACK_ALLOC, addr,
3886
+
gfpflags & ~(__GFP_DIRECT_RECLAIM));
3887
3887
3888
3888
return freelist;
3889
3889
}
···
3920
3910
goto new_objects;
3921
3911
3922
3912
if (s->flags & SLAB_STORE_USER)
3923
-
set_track(s, freelist, TRACK_ALLOC, addr);
3913
+
set_track(s, freelist, TRACK_ALLOC, addr,
3914
+
gfpflags & ~(__GFP_DIRECT_RECLAIM));
3924
3915
3925
3916
return freelist;
3926
3917
}
···
4432
4421
unsigned long flags;
4433
4422
depot_stack_handle_t handle = 0;
4434
4423
4424
+
/*
4425
+
* We cannot use GFP_NOWAIT as there are callsites where waking up
4426
+
* kswapd could deadlock
4427
+
*/
4435
4428
if (s->flags & SLAB_STORE_USER)
4436
-
handle = set_track_prepare();
4429
+
handle = set_track_prepare(__GFP_NOWARN);
4437
4430
4438
4431
spin_lock_irqsave(&n->list_lock, flags);
4439
4432