WSL2-Linux-Kernel/mm
Qian Cai 1649652908 mm/slab.c: fix an infinite loop in leaks_show()
[ Upstream commit 745e10146c ]

"cat /proc/slab_allocators" could hang forever on SMP machines with
kmemleak or object debugging enabled due to other CPUs running do_drain()
will keep making kmemleak_object or debug_objects_cache dirty and unable
to escape the first loop in leaks_show(),

do {
	set_store_user_clean(cachep);
	drain_cpu_caches(cachep);
	...

} while (!is_store_user_clean(cachep));

For example,

do_drain
  slabs_destroy
    slab_destroy
      kmem_cache_free
        __cache_free
          ___cache_free
            kmemleak_free_recursive
              delete_object_full
                __delete_object
                  put_object
                    free_object_rcu
                      kmem_cache_free
                        cache_free_debugcheck --> dirty kmemleak_object

One approach is to check cachep->name and skip both kmemleak_object and
debug_objects_cache in leaks_show().  The other is to set store_user_clean
after drain_cpu_caches() which leaves a small window between
drain_cpu_caches() and set_store_user_clean() where per-CPU caches could
be dirty again lead to slightly wrong information has been stored but
could also speed up things significantly which sounds like a good
compromise.  For example,

 # cat /proc/slab_allocators
 0m42.778s # 1st approach
 0m0.737s  # 2nd approach

[akpm@linux-foundation.org: tweak comment]
Link: http://lkml.kernel.org/r/20190411032635.10325-1-cai@lca.pw
Fixes: d31676dfde ("mm/slab: alternative implementation for DEBUG_SLAB_LEAK")
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-06-15 11:54:51 +02:00
..
kasan kasan: fix shadow_size calculation error in kasan_module_alloc 2018-08-24 13:09:12 +02:00
Kconfig mm/hmm: select mmu notifier when selecting HMM 2019-06-15 11:54:51 +02:00
Kconfig.debug kmemcheck: rip it out 2018-02-22 15:42:24 +01:00
Makefile kmemcheck: rip it out 2018-02-22 15:42:24 +01:00
backing-dev.c writeback: synchronize sync(2) against cgroup writeback membership switches 2019-03-05 17:58:01 +01:00
balloon_compaction.c virtio_balloon: fix deadlock on OOM 2018-10-13 09:27:30 +02:00
bootmem.c
cleancache.c
cma.c mm/cma.c: fix the bitmap status to show failed allocation reason 2019-06-15 11:54:51 +02:00
cma.h
cma_debug.c mm/cma_debug.c: fix the break condition in cma_maxchunk_get() 2019-06-15 11:54:51 +02:00
compaction.c
debug.c mm: get rid of vmacache_flush_all() entirely 2018-09-19 22:43:48 +02:00
debug_page_ref.c
dmapool.c
early_ioremap.c mm/early_ioremap: Fix boot hang with earlyprintk=efi,keep 2018-02-25 11:08:03 +01:00
fadvise.c mm/fadvise.c: fix signed overflow UBSAN complaint 2018-09-15 09:45:28 +02:00
failslab.c
filemap.c mm/filemap.c: fix NULL pointer in page_cache_tree_insert() 2018-04-24 09:36:39 +02:00
frame_vector.c mm/frame_vector.c: release a semaphore in 'get_vaddr_frames()' 2018-03-03 10:24:21 +01:00
frontswap.c
gup.c mm: prevent get_user_pages() from overflowing page refcount 2019-05-04 09:15:17 +02:00
highmem.c
hmm.c mm, hmm: mark hmm_devmem_{add, add_resource} EXPORT_SYMBOL_GPL 2019-01-13 10:01:02 +01:00
huge_memory.c mm/huge_memory: fix lockdep complaint on 32-bit i_size_read() 2018-12-05 19:41:08 +01:00
hugetlb.c hugetlbfs: on restore reserve error path retain subpool reservation 2019-06-15 11:54:51 +02:00
hugetlb_cgroup.c
hwpoison-inject.c
init-mm.c
internal.h
interval_tree.c
khugepaged.c mm/khugepaged: collapse_shmem() do not crash on Compound 2018-12-05 19:41:09 +01:00
kmemleak-test.c
kmemleak.c mm/kmemleak.c: fix unused-function warning 2019-05-08 07:20:53 +02:00
ksm.c mm/ksm.c: ignore STABLE_FLAG of rmap_item->address in rmap_walk_ksm() 2018-07-03 11:25:03 +02:00
list_lru.c memcg: make it work on sparse non-0-node systems 2019-06-09 09:18:17 +02:00
maccess.c
madvise.c mm: madvise(MADV_DODUMP): allow hugetlbfs pages 2018-10-10 08:54:22 +02:00
memblock.c Revert "mm: page_alloc: skip over regions of invalid pfns where possible" 2018-03-28 18:24:39 +02:00
memcontrol.c memcg: remove memcg_cgroup::id from IDR on mem_cgroup_css_alloc() failure 2018-09-05 09:26:32 +02:00
memory-failure.c mm: hwpoison: fix thp split handing in soft_offline_in_use_page() 2019-03-23 14:35:24 +01:00
memory.c mm/memory.c: fix modifying of page protection by insert_pfn() 2019-05-16 19:42:31 +02:00
memory_hotplug.c mm, memory_hotplug: test_pages_in_a_zone do not pass the end of zone 2019-03-13 14:03:18 -07:00
mempolicy.c mm, mempolicy: fix uninit memory access 2019-04-05 22:31:27 +02:00
mempool.c
memtest.c
migrate.c mm/migrate.c: add missing flush_dcache_page for non-mapped page migrate 2019-04-03 06:25:20 +02:00
mincore.c mm/mincore.c: make mincore() more conservative 2019-05-21 18:50:16 +02:00
mlock.c
mm_init.c
mmap.c coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping 2019-04-27 09:35:37 +02:00
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings 2018-08-15 18:12:51 +02:00
mremap.c mremap: properly flush TLB before releasing the page 2018-10-20 09:48:53 +02:00
msync.c
nobootmem.c
nommu.c
oom_kill.c mm, oom: fix use-after-free in oom_kill_process 2019-02-06 17:31:36 +01:00
page-writeback.c mm/page-writeback.c: don't break integrity writeback on ->writepage() error 2019-01-26 09:37:06 +01:00
page_alloc.c mem-hotplug: fix node spanned pages when we have a node with only ZONE_MOVABLE 2019-06-15 11:54:51 +02:00
page_counter.c
page_ext.c mm/page_ext.c: fix an imbalance with kmemleak 2019-04-05 22:31:27 +02:00
page_idle.c mm: thp: fix potential clearing to referenced flag in page_idle_clear_pte_refs_one() 2018-05-30 07:52:24 +02:00
page_io.c
page_isolation.c
page_owner.c mm/page_owner: fix recursion bug after changing skip entries 2018-05-30 07:52:21 +02:00
page_poison.c page_poison: play nicely with KASAN 2019-04-05 22:31:28 +02:00
page_vma_mapped.c mm/rmap: map_pte() was not handling private ZONE_DEVICE page properly 2018-11-13 11:15:08 -08:00
pagewalk.c mm/pagewalk.c: report holes in hugetlb ranges 2017-11-24 08:37:04 +01:00
percpu-internal.h
percpu-km.c percpu: convert spin_lock_irq to spin_lock_irqsave. 2019-02-12 19:46:05 +01:00
percpu-stats.c
percpu-vm.c percpu: add __GFP_NORETRY semantics to the percpu balancing path 2018-04-08 14:26:29 +02:00
percpu.c percpu: stop printing kernel addresses 2019-04-27 09:35:41 +02:00
pgtable-generic.c
process_vm_access.c
quicklist.c
readahead.c readahead: stricter check for bdi io_pages 2018-09-09 19:55:53 +02:00
rmap.c mm: migration: fix migration of huge PMD shared pages 2018-10-13 09:27:22 +02:00
rodata_test.c
shmem.c tmpfs: fix uninitialized return value in shmem_link 2019-03-23 14:35:17 +01:00
slab.c mm/slab.c: fix an infinite loop in leaks_show() 2019-06-15 11:54:51 +02:00
slab.h kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2018-02-22 15:42:23 +01:00
slab_common.c mm: don't warn about large allocations for slab 2018-12-01 09:42:51 +01:00
slob.c
slub.c slub: make ->cpu_partial unsigned int 2018-10-03 17:00:55 -07:00
sparse-vmemmap.c
sparse.c mm: sections are not offlined during memory hotremove 2018-05-16 10:10:27 +02:00
swap.c
swap_cgroup.c
swap_slots.c
swap_state.c
swapfile.c mm/swap: use nr_node_ids for avail_lists in swap_info_struct 2019-01-26 09:37:06 +01:00
truncate.c mm: cleancache: fix corruption on missed inode invalidation 2018-12-08 13:03:40 +01:00
usercopy.c
userfaultfd.c hugetlb: use same fault hash key for shared and private mappings 2019-05-31 06:47:12 -07:00
util.c mm: page_mapped: don't assume compound page is huge or THP 2019-01-16 22:07:11 +01:00
vmacache.c mm: get rid of vmacache_flush_all() entirely 2018-09-19 22:43:48 +02:00
vmalloc.c mm/vmalloc.c: fix kernel BUG at mm/vmalloc.c:512! 2019-04-05 22:31:27 +02:00
vmpressure.c
vmscan.c mm: fix inactive list balancing between NUMA nodes and cgroups 2019-05-16 19:42:22 +02:00
vmstat.c mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n 2019-04-27 09:35:41 +02:00
workingset.c
z3fold.c z3fold: fix possible reclaim races 2018-12-01 09:42:54 +01:00
zbud.c
zpool.c
zsmalloc.c zsmalloc: calling zs_map_object() from irq is a bug 2017-12-14 09:53:10 +01:00
zswap.c zswap: re-check zswap_is_full() after do zswap_shrink() 2018-09-05 09:26:30 +02:00