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authorLinus Torvalds <torvalds@linux-foundation.org>2022-12-12 09:13:06 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2022-12-12 09:13:06 -0800
commit893660b0e1c8d127960ae921f55983b435664e15 (patch)
tree1cc9a3f9364af669964aa12d81c617e31bdb82e2 /mm
parent98d0052d0d9dcd5323833482712b5799ed0bbb0b (diff)
parentdc19745ad0e46c1a069540973e376cff0130443c (diff)
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Merge tag 'slab-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab
Pull slab updates from Vlastimil Babka: - SLOB deprecation and SLUB_TINY The SLOB allocator adds maintenance burden and stands in the way of API improvements [1]. Deprecate it by renaming the config option (to make users notice) to CONFIG_SLOB_DEPRECATED with updated help text. SLUB should be used instead as SLAB will be the next on the removal list. Based on reports from a riscv k210 board with 8MB RAM, add a CONFIG_SLUB_TINY option to minimize SLUB's memory usage at the expense of scalability. This has resolved the k210 regression [2] so in case there are no others (that wouldn't be resolvable by further tweaks to SLUB_TINY) plan is to remove SLOB in a few cycles. Existing defconfigs with CONFIG_SLOB are converted to CONFIG_SLUB_TINY. - kmalloc() slub_debug redzone improvements A series from Feng Tang that builds on the tracking or requested size for kmalloc() allocations (for caches with debugging enabled) added in 6.1, to make redzone checks consider the requested size and not the rounded up one, in order to catch more subtle buffer overruns. Includes new slub_kunit test. - struct slab fields reordering to accomodate larger rcu_head RCU folks would like to grow rcu_head with debugging options, which breaks current struct slab layout's assumptions, so reorganize it to make this possible. - Miscellaneous improvements/fixes: - __alloc_size checking compiler workaround (Kees Cook) - Optimize and cleanup SLUB's sysfs init (Rasmus Villemoes) - Make SLAB compatible with PROVE_RAW_LOCK_NESTING (Jiri Kosina) - Correct SLUB's percpu allocation estimates (Baoquan He) - Re-enableS LUB's run-time failslab sysfs control (Alexander Atanasov) - Make tools/vm/slabinfo more user friendly when not run as root (Rong Tao) - Dead code removal in SLUB (Hyeonggon Yoo) * tag 'slab-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (31 commits) mm, slob: rename CONFIG_SLOB to CONFIG_SLOB_DEPRECATED mm, slub: don't aggressively inline with CONFIG_SLUB_TINY mm, slub: remove percpu slabs with CONFIG_SLUB_TINY mm, slub: split out allocations from pre/post hooks mm/slub, kunit: Add a test case for kmalloc redzone check mm/slub, kunit: add SLAB_SKIP_KFENCE flag for cache creation mm, slub: refactor free debug processing mm, slab: ignore SLAB_RECLAIM_ACCOUNT with CONFIG_SLUB_TINY mm, slub: don't create kmalloc-rcl caches with CONFIG_SLUB_TINY mm, slub: lower the default slub_max_order with CONFIG_SLUB_TINY mm, slub: retain no free slabs on partial list with CONFIG_SLUB_TINY mm, slub: disable SYSFS support with CONFIG_SLUB_TINY mm, slub: add CONFIG_SLUB_TINY mm, slab: ignore hardened usercopy parameters when disabled slab: Remove special-casing of const 0 size allocations slab: Clean up SLOB vs kmalloc() definition mm/sl[au]b: rearrange struct slab fields to allow larger rcu_head mm/migrate: make isolate_movable_page() skip slab pages mm/slab: move and adjust kernel-doc for kmem_cache_alloc mm/slub, percpu: correct the calculation of early percpu allocation size ...
Diffstat (limited to 'mm')
-rw-r--r--mm/Kconfig38
-rw-r--r--mm/Kconfig.debug2
-rw-r--r--mm/kasan/generic.c19
-rw-r--r--mm/migrate.c15
-rw-r--r--mm/slab.c113
-rw-r--r--mm/slab.h86
-rw-r--r--mm/slab_common.c27
-rw-r--r--mm/slub.c553
8 files changed, 567 insertions, 286 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index 57e1d8c5b505..623d95659ff9 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -219,17 +219,43 @@ config SLUB
and has enhanced diagnostics. SLUB is the default choice for
a slab allocator.
-config SLOB
+config SLOB_DEPRECATED
depends on EXPERT
- bool "SLOB (Simple Allocator)"
+ bool "SLOB (Simple Allocator - DEPRECATED)"
depends on !PREEMPT_RT
help
+ Deprecated and scheduled for removal in a few cycles. SLUB
+ recommended as replacement. CONFIG_SLUB_TINY can be considered
+ on systems with 16MB or less RAM.
+
+ If you need SLOB to stay, please contact linux-mm@kvack.org and
+ people listed in the SLAB ALLOCATOR section of MAINTAINERS file,
+ with your use case.
+
SLOB replaces the stock allocator with a drastically simpler
allocator. SLOB is generally more space efficient but
does not perform as well on large systems.
endchoice
+config SLOB
+ bool
+ default y
+ depends on SLOB_DEPRECATED
+
+config SLUB_TINY
+ bool "Configure SLUB for minimal memory footprint"
+ depends on SLUB && EXPERT
+ select SLAB_MERGE_DEFAULT
+ help
+ Configures the SLUB allocator in a way to achieve minimal memory
+ footprint, sacrificing scalability, debugging and other features.
+ This is intended only for the smallest system that had used the
+ SLOB allocator and is not recommended for systems with more than
+ 16MB RAM.
+
+ If unsure, say N.
+
config SLAB_MERGE_DEFAULT
bool "Allow slab caches to be merged"
default y
@@ -247,7 +273,7 @@ config SLAB_MERGE_DEFAULT
config SLAB_FREELIST_RANDOM
bool "Randomize slab freelist"
- depends on SLAB || SLUB
+ depends on SLAB || (SLUB && !SLUB_TINY)
help
Randomizes the freelist order used on creating new pages. This
security feature reduces the predictability of the kernel slab
@@ -255,7 +281,7 @@ config SLAB_FREELIST_RANDOM
config SLAB_FREELIST_HARDENED
bool "Harden slab freelist metadata"
- depends on SLAB || SLUB
+ depends on SLAB || (SLUB && !SLUB_TINY)
help
Many kernel heap attacks try to target slab cache metadata and
other infrastructure. This options makes minor performance
@@ -267,7 +293,7 @@ config SLAB_FREELIST_HARDENED
config SLUB_STATS
default n
bool "Enable SLUB performance statistics"
- depends on SLUB && SYSFS
+ depends on SLUB && SYSFS && !SLUB_TINY
help
SLUB statistics are useful to debug SLUBs allocation behavior in
order find ways to optimize the allocator. This should never be
@@ -279,7 +305,7 @@ config SLUB_STATS
config SLUB_CPU_PARTIAL
default y
- depends on SLUB && SMP
+ depends on SLUB && SMP && !SLUB_TINY
bool "SLUB per cpu partial cache"
help
Per cpu partial caches accelerate objects allocation and freeing
diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug
index ce8dded36de9..fca699ad1fb0 100644
--- a/mm/Kconfig.debug
+++ b/mm/Kconfig.debug
@@ -56,7 +56,7 @@ config DEBUG_SLAB
config SLUB_DEBUG
default y
bool "Enable SLUB debugging support" if EXPERT
- depends on SLUB && SYSFS
+ depends on SLUB && SYSFS && !SLUB_TINY
select STACKDEPOT if STACKTRACE_SUPPORT
help
SLUB has extensive debug support features. Disabling these can
diff --git a/mm/kasan/generic.c b/mm/kasan/generic.c
index d8b5590f9484..b076f597a378 100644
--- a/mm/kasan/generic.c
+++ b/mm/kasan/generic.c
@@ -450,15 +450,22 @@ void kasan_init_object_meta(struct kmem_cache *cache, const void *object)
__memset(alloc_meta, 0, sizeof(*alloc_meta));
}
-size_t kasan_metadata_size(struct kmem_cache *cache)
+size_t kasan_metadata_size(struct kmem_cache *cache, bool in_object)
{
+ struct kasan_cache *info = &cache->kasan_info;
+
if (!kasan_requires_meta())
return 0;
- return (cache->kasan_info.alloc_meta_offset ?
- sizeof(struct kasan_alloc_meta) : 0) +
- ((cache->kasan_info.free_meta_offset &&
- cache->kasan_info.free_meta_offset != KASAN_NO_FREE_META) ?
- sizeof(struct kasan_free_meta) : 0);
+
+ if (in_object)
+ return (info->free_meta_offset ?
+ 0 : sizeof(struct kasan_free_meta));
+ else
+ return (info->alloc_meta_offset ?
+ sizeof(struct kasan_alloc_meta) : 0) +
+ ((info->free_meta_offset &&
+ info->free_meta_offset != KASAN_NO_FREE_META) ?
+ sizeof(struct kasan_free_meta) : 0);
}
static void __kasan_record_aux_stack(void *addr, bool can_alloc)
diff --git a/mm/migrate.c b/mm/migrate.c
index dff333593a8a..1ee0719bd7a1 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -74,13 +74,22 @@ int isolate_movable_page(struct page *page, isolate_mode_t mode)
if (unlikely(!get_page_unless_zero(page)))
goto out;
+ if (unlikely(PageSlab(page)))
+ goto out_putpage;
+ /* Pairs with smp_wmb() in slab freeing, e.g. SLUB's __free_slab() */
+ smp_rmb();
/*
- * Check PageMovable before holding a PG_lock because page's owner
- * assumes anybody doesn't touch PG_lock of newly allocated page
- * so unconditionally grabbing the lock ruins page's owner side.
+ * Check movable flag before taking the page lock because
+ * we use non-atomic bitops on newly allocated page flags so
+ * unconditionally grabbing the lock ruins page's owner side.
*/
if (unlikely(!__PageMovable(page)))
goto out_putpage;
+ /* Pairs with smp_wmb() in slab allocation, e.g. SLUB's alloc_slab_page() */
+ smp_rmb();
+ if (unlikely(PageSlab(page)))
+ goto out_putpage;
+
/*
* As movable pages are not isolated from LRU lists, concurrent
* compaction threads can race against page migration functions
diff --git a/mm/slab.c b/mm/slab.c
index 59c8e28f7b6a..7a269db050ee 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -234,7 +234,7 @@ static void kmem_cache_node_init(struct kmem_cache_node *parent)
parent->shared = NULL;
parent->alien = NULL;
parent->colour_next = 0;
- spin_lock_init(&parent->list_lock);
+ raw_spin_lock_init(&parent->list_lock);
parent->free_objects = 0;
parent->free_touched = 0;
}
@@ -559,9 +559,9 @@ static noinline void cache_free_pfmemalloc(struct kmem_cache *cachep,
slab_node = slab_nid(slab);
n = get_node(cachep, slab_node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
free_block(cachep, &objp, 1, slab_node, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
slabs_destroy(cachep, &list);
}
@@ -684,7 +684,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
struct kmem_cache_node *n = get_node(cachep, node);
if (ac->avail) {
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
/*
* Stuff objects into the remote nodes shared array first.
* That way we could avoid the overhead of putting the objects
@@ -695,7 +695,7 @@ static void __drain_alien_cache(struct kmem_cache *cachep,
free_block(cachep, ac->entry, ac->avail, node, list);
ac->avail = 0;
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
}
}
@@ -768,9 +768,9 @@ static int __cache_free_alien(struct kmem_cache *cachep, void *objp,
slabs_destroy(cachep, &list);
} else {
n = get_node(cachep, slab_node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
free_block(cachep, &objp, 1, slab_node, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
slabs_destroy(cachep, &list);
}
return 1;
@@ -811,10 +811,10 @@ static int init_cache_node(struct kmem_cache *cachep, int node, gfp_t gfp)
*/
n = get_node(cachep, node);
if (n) {
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
n->free_limit = (1 + nr_cpus_node(node)) * cachep->batchcount +
cachep->num;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
return 0;
}
@@ -893,7 +893,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
goto fail;
n = get_node(cachep, node);
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
if (n->shared && force_change) {
free_block(cachep, n->shared->entry,
n->shared->avail, node, &list);
@@ -911,7 +911,7 @@ static int setup_kmem_cache_node(struct kmem_cache *cachep,
new_alien = NULL;
}
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
/*
@@ -950,7 +950,7 @@ static void cpuup_canceled(long cpu)
if (!n)
continue;
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
/* Free limit for this kmem_cache_node */
n->free_limit -= cachep->batchcount;
@@ -961,7 +961,7 @@ static void cpuup_canceled(long cpu)
nc->avail = 0;
if (!cpumask_empty(mask)) {
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
goto free_slab;
}
@@ -975,7 +975,7 @@ static void cpuup_canceled(long cpu)
alien = n->alien;
n->alien = NULL;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
kfree(shared);
if (alien) {
@@ -1159,7 +1159,7 @@ static void __init init_list(struct kmem_cache *cachep, struct kmem_cache_node *
/*
* Do not assume that spinlocks can be initialized via memcpy:
*/
- spin_lock_init(&ptr->list_lock);
+ raw_spin_lock_init(&ptr->list_lock);
MAKE_ALL_LISTS(cachep, ptr, nodeid);
cachep->node[nodeid] = ptr;
@@ -1330,11 +1330,11 @@ slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
for_each_kmem_cache_node(cachep, node, n) {
unsigned long total_slabs, free_slabs, free_objs;
- spin_lock_irqsave(&n->list_lock, flags);
+ raw_spin_lock_irqsave(&n->list_lock, flags);
total_slabs = n->total_slabs;
free_slabs = n->free_slabs;
free_objs = n->free_objects;
- spin_unlock_irqrestore(&n->list_lock, flags);
+ raw_spin_unlock_irqrestore(&n->list_lock, flags);
pr_warn(" node %d: slabs: %ld/%ld, objs: %ld/%ld\n",
node, total_slabs - free_slabs, total_slabs,
@@ -1370,6 +1370,8 @@ static struct slab *kmem_getpages(struct kmem_cache *cachep, gfp_t flags,
account_slab(slab, cachep->gfporder, cachep, flags);
__folio_set_slab(folio);
+ /* Make the flag visible before any changes to folio->mapping */
+ smp_wmb();
/* Record if ALLOC_NO_WATERMARKS was set when allocating the slab */
if (sk_memalloc_socks() && page_is_pfmemalloc(folio_page(folio, 0)))
slab_set_pfmemalloc(slab);
@@ -1387,9 +1389,11 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab)
BUG_ON(!folio_test_slab(folio));
__slab_clear_pfmemalloc(slab);
- __folio_clear_slab(folio);
page_mapcount_reset(folio_page(folio, 0));
folio->mapping = NULL;
+ /* Make the mapping reset visible before clearing the flag */
+ smp_wmb();
+ __folio_clear_slab(folio);
if (current->reclaim_state)
current->reclaim_state->reclaimed_slab += 1 << order;
@@ -2096,7 +2100,7 @@ static void check_spinlock_acquired(struct kmem_cache *cachep)
{
#ifdef CONFIG_SMP
check_irq_off();
- assert_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
+ assert_raw_spin_locked(&get_node(cachep, numa_mem_id())->list_lock);
#endif
}
@@ -2104,7 +2108,7 @@ static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node)
{
#ifdef CONFIG_SMP
check_irq_off();
- assert_spin_locked(&get_node(cachep, node)->list_lock);
+ assert_raw_spin_locked(&get_node(cachep, node)->list_lock);
#endif
}
@@ -2144,9 +2148,9 @@ static void do_drain(void *arg)
check_irq_off();
ac = cpu_cache_get(cachep);
n = get_node(cachep, node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
free_block(cachep, ac->entry, ac->avail, node, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
ac->avail = 0;
slabs_destroy(cachep, &list);
}
@@ -2164,9 +2168,9 @@ static void drain_cpu_caches(struct kmem_cache *cachep)
drain_alien_cache(cachep, n->alien);
for_each_kmem_cache_node(cachep, node, n) {
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
drain_array_locked(cachep, n->shared, node, true, &list);
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
}
@@ -2188,10 +2192,10 @@ static int drain_freelist(struct kmem_cache *cache,
nr_freed = 0;
while (nr_freed < tofree && !list_empty(&n->slabs_free)) {
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
p = n->slabs_free.prev;
if (p == &n->slabs_free) {
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
goto out;
}
@@ -2204,7 +2208,7 @@ static int drain_freelist(struct kmem_cache *cache,
* to the cache.
*/
n->free_objects -= cache->num;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slab_destroy(cache, slab);
nr_freed++;
}
@@ -2629,7 +2633,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab)
INIT_LIST_HEAD(&slab->slab_list);
n = get_node(cachep, slab_nid(slab));
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
n->total_slabs++;
if (!slab->active) {
list_add_tail(&slab->slab_list, &n->slabs_free);
@@ -2639,7 +2643,7 @@ static void cache_grow_end(struct kmem_cache *cachep, struct slab *slab)
STATS_INC_GROWN(cachep);
n->free_objects += cachep->num - slab->active;
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
}
@@ -2805,7 +2809,7 @@ static struct slab *get_first_slab(struct kmem_cache_node *n, bool pfmemalloc)
{
struct slab *slab;
- assert_spin_locked(&n->list_lock);
+ assert_raw_spin_locked(&n->list_lock);
slab = list_first_entry_or_null(&n->slabs_partial, struct slab,
slab_list);
if (!slab) {
@@ -2832,10 +2836,10 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
if (!gfp_pfmemalloc_allowed(flags))
return NULL;
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
slab = get_first_slab(n, true);
if (!slab) {
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
return NULL;
}
@@ -2844,7 +2848,7 @@ static noinline void *cache_alloc_pfmemalloc(struct kmem_cache *cachep,
fixup_slab_list(cachep, n, slab, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
return obj;
@@ -2903,7 +2907,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
if (!n->free_objects && (!shared || !shared->avail))
goto direct_grow;
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
shared = READ_ONCE(n->shared);
/* See if we can refill from the shared array */
@@ -2927,7 +2931,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
must_grow:
n->free_objects -= ac->avail;
alloc_done:
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
direct_grow:
@@ -3147,7 +3151,7 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
BUG_ON(!n);
check_irq_off();
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
slab = get_first_slab(n, false);
if (!slab)
goto must_grow;
@@ -3165,12 +3169,12 @@ static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
fixup_slab_list(cachep, n, slab, &list);
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
fixup_objfreelist_debug(cachep, &list);
return obj;
must_grow:
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
slab = cache_grow_begin(cachep, gfp_exact_node(flags), nodeid);
if (slab) {
/* This slab isn't counted yet so don't update free_objects */
@@ -3254,7 +3258,8 @@ slab_alloc_node(struct kmem_cache *cachep, struct list_lru *lru, gfp_t flags,
init = slab_want_init_on_alloc(flags, cachep);
out:
- slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init);
+ slab_post_alloc_hook(cachep, objcg, flags, 1, &objp, init,
+ cachep->object_size);
return objp;
}
@@ -3325,7 +3330,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
check_irq_off();
n = get_node(cachep, node);
- spin_lock(&n->list_lock);
+ raw_spin_lock(&n->list_lock);
if (n->shared) {
struct array_cache *shared_array = n->shared;
int max = shared_array->limit - shared_array->avail;
@@ -3354,7 +3359,7 @@ free_done:
STATS_SET_FREEABLE(cachep, i);
}
#endif
- spin_unlock(&n->list_lock);
+ raw_spin_unlock(&n->list_lock);
ac->avail -= batchcount;
memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail);
slabs_destroy(cachep, &list);
@@ -3446,16 +3451,6 @@ void *__kmem_cache_alloc_lru(struct kmem_cache *cachep, struct list_lru *lru,
return ret;
}
-/**
- * kmem_cache_alloc - Allocate an object
- * @cachep: The cache to allocate from.
- * @flags: See kmalloc().
- *
- * Allocate an object from this cache. The flags are only relevant
- * if the cache has no available objects.
- *
- * Return: pointer to the new object or %NULL in case of error
- */
void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
{
return __kmem_cache_alloc_lru(cachep, NULL, flags);
@@ -3507,13 +3502,13 @@ int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size,
* Done outside of the IRQ disabled section.
*/
slab_post_alloc_hook(s, objcg, flags, size, p,
- slab_want_init_on_alloc(flags, s));
+ slab_want_init_on_alloc(flags, s), s->object_size);
/* FIXME: Trace call missing. Christoph would like a bulk variant */
return size;
error:
local_irq_enable();
cache_alloc_debugcheck_after_bulk(s, flags, i, p, _RET_IP_);
- slab_post_alloc_hook(s, objcg, flags, i, p, false);
+ slab_post_alloc_hook(s, objcg, flags, i, p, false, s->object_size);
kmem_cache_free_bulk(s, i, p);
return 0;
}
@@ -3721,9 +3716,9 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
node = cpu_to_mem(cpu);
n = get_node(cachep, node);
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
free_block(cachep, ac->entry, ac->avail, node, &list);
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
}
free_percpu(prev);
@@ -3815,9 +3810,9 @@ static void drain_array(struct kmem_cache *cachep, struct kmem_cache_node *n,
return;
}
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
drain_array_locked(cachep, ac, node, false, &list);
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
slabs_destroy(cachep, &list);
}
@@ -3901,7 +3896,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
for_each_kmem_cache_node(cachep, node, n) {
check_irq_on();
- spin_lock_irq(&n->list_lock);
+ raw_spin_lock_irq(&n->list_lock);
total_slabs += n->total_slabs;
free_slabs += n->free_slabs;
@@ -3910,7 +3905,7 @@ void get_slabinfo(struct kmem_cache *cachep, struct slabinfo *sinfo)
if (n->shared)
shared_avail += n->shared->avail;
- spin_unlock_irq(&n->list_lock);
+ raw_spin_unlock_irq(&n->list_lock);
}
num_objs = total_slabs * cachep->num;
active_slabs = total_slabs - free_slabs;
diff --git a/mm/slab.h b/mm/slab.h
index 0202a8c2f0d2..7cc432969945 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -11,37 +11,43 @@ struct slab {
#if defined(CONFIG_SLAB)
+ struct kmem_cache *slab_cache;
union {
- struct list_head slab_list;
+ struct {
+ struct list_head slab_list;
+ void *freelist; /* array of free object indexes */
+ void *s_mem; /* first object */
+ };
struct rcu_head rcu_head;
};
- struct kmem_cache *slab_cache;
- void *freelist; /* array of free object indexes */
- void *s_mem; /* first object */
unsigned int active;
#elif defined(CONFIG_SLUB)
- union {
- struct list_head slab_list;
- struct rcu_head rcu_head;
-#ifdef CONFIG_SLUB_CPU_PARTIAL
- struct {
- struct slab *next;
- int slabs; /* Nr of slabs left */
- };
-#endif
- };
struct kmem_cache *slab_cache;
- /* Double-word boundary */
- void *freelist; /* first free object */
union {
- unsigned long counters;
struct {
- unsigned inuse:16;
- unsigned objects:15;
- unsigned frozen:1;
+ union {
+ struct list_head slab_list;
+#ifdef CONFIG_SLUB_CPU_PARTIAL
+ struct {
+ struct slab *next;
+ int slabs; /* Nr of slabs left */
+ };
+#endif
+ };
+ /* Double-word boundary */
+ void *freelist; /* first free object */
+ union {
+ unsigned long counters;
+ struct {
+ unsigned inuse:16;
+ unsigned objects:15;
+ unsigned frozen:1;
+ };
+ };
};
+ struct rcu_head rcu_head;
};
unsigned int __unused;
@@ -66,9 +72,10 @@ struct slab {
#define SLAB_MATCH(pg, sl) \
static_assert(offsetof(struct page, pg) == offsetof(struct slab, sl))
SLAB_MATCH(flags, __page_flags);
-SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */
#ifndef CONFIG_SLOB
-SLAB_MATCH(rcu_head, rcu_head);
+SLAB_MATCH(compound_head, slab_cache); /* Ensure bit 0 is clear */
+#else
+SLAB_MATCH(compound_head, slab_list); /* Ensure bit 0 is clear */
#endif
SLAB_MATCH(_refcount, __page_refcount);
#ifdef CONFIG_MEMCG
@@ -76,6 +83,9 @@ SLAB_MATCH(memcg_data, memcg_data);
#endif
#undef SLAB_MATCH
static_assert(sizeof(struct slab) <= sizeof(struct page));
+#if defined(CONFIG_HAVE_CMPXCHG_DOUBLE) && defined(CONFIG_SLUB)
+static_assert(IS_ALIGNED(offsetof(struct slab, freelist), 2*sizeof(void *)));
+#endif
/**
* folio_slab - Converts from folio to slab.
@@ -207,8 +217,6 @@ struct kmem_cache {
unsigned int size; /* The aligned/padded/added on size */
unsigned int align; /* Alignment as calculated */
slab_flags_t flags; /* Active flags on the slab */
- unsigned int useroffset;/* Usercopy region offset */
- unsigned int usersize; /* Usercopy region size */
const char *name; /* Slab name for sysfs */
int refcount; /* Use counter */
void (*ctor)(void *); /* Called on object slot creation */
@@ -336,7 +344,8 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
SLAB_ACCOUNT)
#elif defined(CONFIG_SLUB)
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
- SLAB_TEMPORARY | SLAB_ACCOUNT | SLAB_NO_USER_FLAGS)
+ SLAB_TEMPORARY | SLAB_ACCOUNT | \
+ SLAB_NO_USER_FLAGS | SLAB_KMALLOC)
#else
#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE)
#endif
@@ -356,6 +365,7 @@ static inline slab_flags_t kmem_cache_flags(unsigned int object_size,
SLAB_RECLAIM_ACCOUNT | \
SLAB_TEMPORARY | \
SLAB_ACCOUNT | \
+ SLAB_KMALLOC | \
SLAB_NO_USER_FLAGS)
bool __kmem_cache_empty(struct kmem_cache *);
@@ -720,13 +730,27 @@ static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
static inline void slab_post_alloc_hook(struct kmem_cache *s,
struct obj_cgroup *objcg, gfp_t flags,
- size_t size, void **p, bool init)
+ size_t size, void **p, bool init,
+ unsigned int orig_size)
{
+ unsigned int zero_size = s->object_size;
size_t i;
flags &= gfp_allowed_mask;
/*
+ * For kmalloc object, the allocated memory size(object_size) is likely
+ * larger than the requested size(orig_size). If redzone check is
+ * enabled for the extra space, don't zero it, as it will be redzoned
+ * soon. The redzone operation for this extra space could be seen as a
+ * replacement of current poisoning under certain debug option, and
+ * won't break other sanity checks.
+ */
+ if (kmem_cache_debug_flags(s, SLAB_STORE_USER | SLAB_RED_ZONE) &&
+ (s->flags & SLAB_KMALLOC))
+ zero_size = orig_size;
+
+ /*
* As memory initialization might be integrated into KASAN,
* kasan_slab_alloc and initialization memset must be
* kept together to avoid discrepancies in behavior.
@@ -736,7 +760,7 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s,
for (i = 0; i < size; i++) {
p[i] = kasan_slab_alloc(s, p[i], flags, init);
if (p[i] && init && !kasan_has_integrated_init())
- memset(p[i], 0, s->object_size);
+ memset(p[i], 0, zero_size);
kmemleak_alloc_recursive(p[i], s->object_size, 1,
s->flags, flags);
kmsan_slab_alloc(s, p[i], flags);
@@ -750,9 +774,8 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s,
* The slab lists for all objects.
*/
struct kmem_cache_node {
- spinlock_t list_lock;
-
#ifdef CONFIG_SLAB
+ raw_spinlock_t list_lock;
struct list_head slabs_partial; /* partial list first, better asm code */
struct list_head slabs_full;
struct list_head slabs_free;
@@ -768,6 +791,7 @@ struct kmem_cache_node {
#endif
#ifdef CONFIG_SLUB
+ spinlock_t list_lock;
unsigned long nr_partial;
struct list_head partial;
#ifdef CONFIG_SLUB_DEBUG
@@ -871,4 +895,8 @@ void __check_heap_object(const void *ptr, unsigned long n,
}
#endif
+#ifdef CONFIG_SLUB_DEBUG
+void skip_orig_size_check(struct kmem_cache *s, const void *object);
+#endif
+
#endif /* MM_SLAB_H */
diff --git a/mm/slab_common.c b/mm/slab_common.c
index 0042fb2730d1..3e49bb830060 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -143,8 +143,10 @@ int slab_unmergeable(struct kmem_cache *s)
if (s->ctor)
return 1;
+#ifdef CONFIG_HARDENED_USERCOPY
if (s->usersize)
return 1;
+#endif
/*
* We may have set a slab to be unmergeable during bootstrap.
@@ -223,8 +225,10 @@ static struct kmem_cache *create_cache(const char *name,
s->size = s->object_size = object_size;
s->align = align;
s->ctor = ctor;
+#ifdef CONFIG_HARDENED_USERCOPY
s->useroffset = useroffset;
s->usersize = usersize;
+#endif
err = __kmem_cache_create(s, flags);
if (err)
@@ -317,7 +321,8 @@ kmem_cache_create_usercopy(const char *name,
flags &= CACHE_CREATE_MASK;
/* Fail closed on bad usersize of useroffset values. */
- if (WARN_ON(!usersize && useroffset) ||
+ if (!IS_ENABLED(CONFIG_HARDENED_USERCOPY) ||
+ WARN_ON(!usersize && useroffset) ||
WARN_ON(size < usersize || size - usersize < useroffset))
usersize = useroffset = 0;
@@ -595,8 +600,8 @@ void kmem_dump_obj(void *object)
ptroffset = ((char *)object - (char *)kp.kp_objp) - kp.kp_data_offset;
pr_cont(" pointer offset %lu", ptroffset);
}
- if (kp.kp_slab_cache && kp.kp_slab_cache->usersize)
- pr_cont(" size %u", kp.kp_slab_cache->usersize);
+ if (kp.kp_slab_cache && kp.kp_slab_cache->object_size)
+ pr_cont(" size %u", kp.kp_slab_cache->object_size);
if (kp.kp_ret)
pr_cont(" allocated at %pS\n", kp.kp_ret);
else
@@ -640,8 +645,10 @@ void __init create_boot_cache(struct kmem_cache *s, const char *name,
align = max(align, size);
s->align = calculate_alignment(flags, align, size);
+#ifdef CONFIG_HARDENED_USERCOPY
s->useroffset = useroffset;
s->usersize = usersize;
+#endif
err = __kmem_cache_create(s, flags);
@@ -766,10 +773,16 @@ EXPORT_SYMBOL(kmalloc_size_roundup);
#define KMALLOC_CGROUP_NAME(sz)
#endif
+#ifndef CONFIG_SLUB_TINY
+#define KMALLOC_RCL_NAME(sz) .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #sz,
+#else
+#define KMALLOC_RCL_NAME(sz)
+#endif
+
#define INIT_KMALLOC_INFO(__size, __short_size) \
{ \
.name[KMALLOC_NORMAL] = "kmalloc-" #__short_size, \
- .name[KMALLOC_RECLAIM] = "kmalloc-rcl-" #__short_size, \
+ KMALLOC_RCL_NAME(__short_size) \
KMALLOC_CGROUP_NAME(__short_size) \
KMALLOC_DMA_NAME(__short_size) \
.size = __size, \
@@ -855,7 +868,7 @@ void __init setup_kmalloc_cache_index_table(void)
static void __init
new_kmalloc_cache(int idx, enum kmalloc_cache_type type, slab_flags_t flags)
{
- if (type == KMALLOC_RECLAIM) {
+ if ((KMALLOC_RECLAIM != KMALLOC_NORMAL) && (type == KMALLOC_RECLAIM)) {
flags |= SLAB_RECLAIM_ACCOUNT;
} else if (IS_ENABLED(CONFIG_MEMCG_KMEM) && (type == KMALLOC_CGROUP)) {
if (mem_cgroup_kmem_disabled()) {
@@ -1037,6 +1050,10 @@ size_t __ksize(const void *object)
return folio_size(folio);
}
+#ifdef CONFIG_SLUB_DEBUG
+ skip_orig_size_check(folio_slab(folio)->slab_cache, object);
+#endif
+
return slab_ksize(folio_slab(folio)->slab_cache);
}
diff --git a/mm/slub.c b/mm/slub.c
index 157527d7101b..891df05a4d45 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -187,6 +187,12 @@ do { \
#define USE_LOCKLESS_FAST_PATH() (false)
#endif
+#ifndef CONFIG_SLUB_TINY
+#define __fastpath_inline __always_inline
+#else
+#define __fastpath_inline
+#endif
+
#ifdef CONFIG_SLUB_DEBUG
#ifdef CONFIG_SLUB_DEBUG_ON
DEFINE_STATIC_KEY_TRUE(slub_debug_enabled);
@@ -241,6 +247,7 @@ static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s)
/* Enable to log cmpxchg failures */
#undef SLUB_DEBUG_CMPXCHG
+#ifndef CONFIG_SLUB_TINY
/*
* Minimum number of partial slabs. These will be left on the partial
* lists even if they are empty. kmem_cache_shrink may reclaim them.
@@ -253,6 +260,10 @@ static inline bool kmem_cache_has_cpu_partial(struct kmem_cache *s)
* sort the partial list by the number of objects in use.
*/
#define MAX_PARTIAL 10
+#else
+#define MIN_PARTIAL 0
+#define MAX_PARTIAL 0
+#endif
#define DEBUG_DEFAULT_FLAGS (SLAB_CONSISTENCY_CHECKS | SLAB_RED_ZONE | \
SLAB_POISON | SLAB_STORE_USER)
@@ -298,7 +309,7 @@ struct track {
enum track_item { TRACK_ALLOC, TRACK_FREE };
-#ifdef CONFIG_SYSFS
+#ifdef SLAB_SUPPORTS_SYSFS
static int sysfs_slab_add(struct kmem_cache *);
static int sysfs_slab_alias(struct kmem_cache *, const char *);
#else