Adrian Huang 2fe20210fc mm: memcg/slab: call flush_memcg_workqueue() only if memcg workqueue is valid ... When booting with amd_iommu=off, the following WARNING message appears: AMD-Vi: AMD IOMMU disabled on kernel command-line ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:2772 flush_workqueue+0x42e/0x450 Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.5.0-rc3-amd-iommu #6 Hardware name: Lenovo ThinkSystem SR655-2S/7D2WRCZ000, BIOS D8E101L-1.00 12/05/2019 RIP: 0010:flush_workqueue+0x42e/0x450 Code: ff 0f 0b e9 7a fd ff ff 4d 89 ef e9 33 fe ff ff 0f 0b e9 7f fd ff ff 0f 0b e9 bc fd ff ff 0f 0b e9 a8 fd ff ff e8 52 2c fe ff <0f> 0b 31 d2 48 c7 c6 e0 88 c5 95 48 c7 c7 d8 ad f0 95 e8 19 f5 04 Call Trace: kmem_cache_destroy+0x69/0x260 iommu_go_to_state+0x40c/0x5ab amd_iommu_prepare+0x16/0x2a irq_remapping_prepare+0x36/0x5f enable_IR_x2apic+0x21/0x172 default_setup_apic_routing+0x12/0x6f apic_intr_mode_init+0x1a1/0x1f1 x86_late_time_init+0x17/0x1c start_kernel+0x480/0x53f secondary_startup_64+0xb6/0xc0 ---[ end trace 30894107c3749449 ]--- x2apic: IRQ remapping doesn't support X2APIC mode x2apic disabled The warning is caused by the calling of 'kmem_cache_destroy()' in free_iommu_resources(). Here is the call path: free_iommu_resources kmem_cache_destroy flush_memcg_workqueue flush_workqueue The root cause is that the IOMMU subsystem runs before the workqueue subsystem, which the variable 'wq_online' is still 'false'. This leads to the statement 'if (WARN_ON(!wq_online))' in flush_workqueue() is 'true'. Since the variable 'memcg_kmem_cache_wq' is not allocated during the time, it is unnecessary to call flush_memcg_workqueue(). This prevents the WARNING message triggered by flush_workqueue(). Link: http://lkml.kernel.org/r/20200103085503.1665-1-ahuang12@lenovo.com Fixes: 92ee383f6d ("mm: fix race between kmem_cache destroy, create and deactivate") Signed-off-by: Adrian Huang <ahuang12@lenovo.com> Reported-by: Xiaochun Lee <lixc17@lenovo.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Joerg Roedel <jroedel@suse.de> 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> Cc: Michal Hocko <mhocko@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2020-01-13 18:19:02 -08:00
..
kasan	kasan: use apply_to_existing_page_range() for releasing vmalloc shadow	2019-12-17 20:59:59 -08:00
backing-dev.c
balloon_compaction.c
cleancache.c
cma_debug.c	mm/cma_debug.c: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops	2019-12-01 12:59:09 -08:00
cma.c	mm/cma.c: switch to bitmap_zalloc() for cma bitmap allocation	2019-12-01 12:59:09 -08:00
cma.h
compaction.c
debug_page_ref.c
debug.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c	mm: drop mmap_sem before calling balance_dirty_pages() in write fault	2019-12-01 06:29:18 -08:00
frame_vector.c
frontswap.c
gup_benchmark.c	mm/gup: fix memory leak in __gup_benchmark_ioctl	2020-01-04 13:55:09 -08:00
gup.c	mm/gup.c: fix comments of __get_user_pages() and get_user_pages_remote()	2019-12-01 06:29:18 -08:00
highmem.c
hmm.c	mm/hmm: remove hmm_range_dma_map and hmm_range_dma_unmap	2019-11-23 19:56:45 -04:00
huge_memory.c	mm/huge_memory.c: thp: fix conflict of above-47bit hint address and PMD alignment	2020-01-13 18:19:01 -08:00
hugetlb_cgroup.c
hugetlb.c	mm/hugetlb: defer freeing of huge pages if in non-task context	2020-01-04 13:55:09 -08:00
hwpoison-inject.c	mm/hwpoison-inject: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops	2019-12-01 12:59:09 -08:00
init-mm.c
internal.h	mm, pcpu: make zone pcp updates and reset internal to the mm	2019-12-01 12:59:06 -08:00
interval_tree.c
Kconfig	mm/Kconfig: fix trivial help text punctuation	2019-12-01 12:59:10 -08:00
Kconfig.debug
khugepaged.c	mm/thp: flush file for !is_shmem PageDirty() case in collapse_file()	2019-12-01 12:59:09 -08:00
kmemleak-test.c
kmemleak.c
ksm.c	* PPC secure guest support	2019-12-04 11:08:30 -08:00
list_lru.c
maccess.c
madvise.c	mm/madvise.c: use PAGE_ALIGN[ED] for range checking	2019-12-01 12:59:09 -08:00
Makefile
mapping_dirty_helpers.c
memblock.c	mm: support memblock alloc on the exact node for sparse_buffer_init()	2019-12-01 12:59:08 -08:00
memcontrol.c	mm: memcg/slab: fix percpu slab vmstats flushing	2020-01-13 18:19:02 -08:00
memfd.c
memory_hotplug.c	mm/memory_hotplug: shrink zones when offlining memory	2020-01-04 13:55:08 -08:00
memory-failure.c	mm/memory-failure.c: use page_shift() in add_to_kill()	2019-12-01 12:59:04 -08:00
memory.c	mm/memory.c: add apply_to_existing_page_range() helper	2019-12-17 20:59:59 -08:00
mempolicy.c	mm, thp: tweak reclaim/compaction effort of local-only and all-node allocations	2020-01-13 18:19:01 -08:00
mempool.c
memremap.c	mm/memory_hotplug: shrink zones when offlining memory	2020-01-04 13:55:08 -08:00
memtest.c
migrate.c	mm: move_pages: return valid node id in status if the page is already on the target node	2020-01-04 13:55:09 -08:00
mincore.c
mlock.c
mm_init.c
mmap.c	arm64: Revert support for execute-only user mappings	2020-01-06 10:10:07 -08:00
mmu_context.c
mmu_gather.c
mmu_notifier.c	hmm related patches for 5.5	2019-11-30 10:33:14 -08:00
mmzone.c
mprotect.c	autonuma: reduce cache footprint when scanning page tables	2019-12-01 12:59:09 -08:00
mremap.c	mm/mmap.c: use IS_ERR_VALUE to check return value of get_unmapped_area	2019-12-01 06:29:19 -08:00
msync.c
nommu.c	mm/mmap.c: rb_parent is not necessary in __vma_link_list()	2019-12-01 06:29:19 -08:00
oom_kill.c	mm/oom: fix pgtables units mismatch in Killed process message	2020-01-04 13:55:09 -08:00
page_alloc.c	mm, debug_pagealloc: don't rely on static keys too early	2020-01-13 18:19:02 -08:00
page_counter.c
page_ext.c
page_idle.c
page_io.c	mm/page_io.c: annotate refault stalls from swap_readpage	2019-12-01 12:59:11 -08:00
page_isolation.c	mm/page_isolation.c: convert SKIP_HWPOISON to MEMORY_OFFLINE	2019-12-01 12:59:04 -08:00
page_owner.c
page_poison.c
page_vma_mapped.c
page-writeback.c	mm/page-writeback.c: improve arithmetic divisions	2020-01-13 18:19:02 -08:00
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c
pgtable-generic.c	asm-generic/mm: stub out p{4,u}d_clear_bad() if __PAGETABLE_P{4,U}D_FOLDED	2019-12-01 06:29:19 -08:00
process_vm_access.c
readahead.c
rmap.c	mm, thp: do not queue fully unmapped pages for deferred split	2019-12-01 12:59:09 -08:00
rodata_test.c
shmem.c	mm/shmem.c: thp, shmem: fix conflict of above-47bit hint address and PMD alignment	2020-01-13 18:19:01 -08:00
shuffle.c
shuffle.h
slab_common.c	mm: memcg/slab: call flush_memcg_workqueue() only if memcg workqueue is valid	2020-01-13 18:19:02 -08:00
slab.c	mm, debug_pagealloc: don't rely on static keys too early	2020-01-13 18:19:02 -08:00
slab.h	mm: clean up and clarify lruvec lookup procedure	2019-12-01 12:59:06 -08:00
slob.c
slub.c	mm, debug_pagealloc: don't rely on static keys too early	2020-01-13 18:19:02 -08:00
sparse-vmemmap.c
sparse.c	mm/memory_hotplug: don't free usage map when removing a re-added early section	2020-01-13 18:19:01 -08:00
swap_cgroup.c
swap_slots.c
swap_state.c
swap.c	mm/swap.c: piggyback lru_add_drain_all() calls	2019-12-01 06:29:19 -08:00
swapfile.c	mm, swap: disallow swapon() on zoned block devices	2019-12-01 06:29:18 -08:00
truncate.c
usercopy.c
userfaultfd.c	mm: fix typos in comments when calling __SetPageUptodate()	2019-12-01 12:59:10 -08:00
util.c	mm/mmap.c: rb_parent is not necessary in __vma_link_list()	2019-12-01 06:29:19 -08:00
vmacache.c
vmalloc.c	mm, debug_pagealloc: don't rely on static keys too early	2020-01-13 18:19:02 -08:00
vmpressure.c
vmscan.c	mm: vmscan: protect shrinker idr replace with CONFIG_MEMCG	2019-12-17 20:59:59 -08:00
vmstat.c	mm/memcontrol: use vmstat names for printing statistics	2019-12-04 19:44:11 -08:00
workingset.c	mm: vmscan: detect file thrashing at the reclaim root	2019-12-01 12:59:07 -08:00
z3fold.c	mm/z3fold.c: add inter-page compaction	2019-12-01 12:59:07 -08:00
zbud.c
zpool.c
zsmalloc.c	mm/zsmalloc.c: fix the migrated zspage statistics.	2020-01-04 13:55:09 -08:00
zswap.c