linux/mm
Mika Westerberg a2b90f1121 bdi: Do not use freezable workqueue
A removable block device, such as NVMe or SSD connected over Thunderbolt
can be hot-removed any time including when the system is suspended. When
device is hot-removed during suspend and the system gets resumed, kernel
first resumes devices and then thaws the userspace including freezable
workqueues. What happens in that case is that the NVMe driver notices
that the device is unplugged and removes it from the system. This ends
up calling bdi_unregister() for the gendisk which then schedules
wb_workfn() to be run one more time.

However, since the bdi_wq is still frozen flush_delayed_work() call in
wb_shutdown() blocks forever halting system resume process. User sees
this as hang as nothing is happening anymore.

Triggering sysrq-w reveals this:

  Workqueue: nvme-wq nvme_remove_dead_ctrl_work [nvme]
  Call Trace:
   ? __schedule+0x2c5/0x630
   ? wait_for_completion+0xa4/0x120
   schedule+0x3e/0xc0
   schedule_timeout+0x1c9/0x320
   ? resched_curr+0x1f/0xd0
   ? wait_for_completion+0xa4/0x120
   wait_for_completion+0xc3/0x120
   ? wake_up_q+0x60/0x60
   __flush_work+0x131/0x1e0
   ? flush_workqueue_prep_pwqs+0x130/0x130
   bdi_unregister+0xb9/0x130
   del_gendisk+0x2d2/0x2e0
   nvme_ns_remove+0xed/0x110 [nvme_core]
   nvme_remove_namespaces+0x96/0xd0 [nvme_core]
   nvme_remove+0x5b/0x160 [nvme]
   pci_device_remove+0x36/0x90
   device_release_driver_internal+0xdf/0x1c0
   nvme_remove_dead_ctrl_work+0x14/0x30 [nvme]
   process_one_work+0x1c2/0x3f0
   worker_thread+0x48/0x3e0
   kthread+0x100/0x140
   ? current_work+0x30/0x30
   ? kthread_park+0x80/0x80
   ret_from_fork+0x35/0x40

This is not limited to NVMes so exactly same issue can be reproduced by
hot-removing SSD (over Thunderbolt) while the system is suspended.

Prevent this from happening by removing WQ_FREEZABLE from bdi_wq.

Reported-by: AceLan Kao <acelan.kao@canonical.com>
Link: https://marc.info/?l=linux-kernel&m=138695698516487
Link: https://bugzilla.kernel.org/show_bug.cgi?id=204385
Link: https://lore.kernel.org/lkml/20191002122136.GD2819@lahna.fi.intel.com/#t
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-06 09:11:35 -06:00
..
kasan mm: introduce compound_nr() 2019-09-24 15:54:08 -07:00
backing-dev.c bdi: Do not use freezable workqueue 2019-10-06 09:11:35 -06:00
balloon_compaction.c mm/balloon_compaction: suppress allocation warnings 2019-09-04 07:42:01 -04:00
cleancache.c Driver Core and debugfs changes for 5.3-rc1 2019-07-12 12:24:03 -07:00
cma_debug.c mm/cma_debug.c: fix the break condition in cma_maxchunk_get() 2019-05-14 09:47:45 -07:00
cma.c mm/cma.c: fail if fixed declaration can't be honored 2019-07-16 19:23:21 -07:00
cma.h
compaction.c mm/compaction.c: remove unnecessary zone parameter in isolate_migratepages() 2019-09-24 15:54:10 -07:00
debug_page_ref.c
debug.c mm: update references to page _refcount 2019-05-14 19:52:47 -07:00
dmapool.c mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options 2019-07-12 11:05:46 -07:00
early_ioremap.c
fadvise.c fs: Export generic_fadvise() 2019-08-30 22:43:58 -07:00
failslab.c mm/failslab.c: by default, do not fail allocations with direct reclaim only 2019-07-12 11:05:43 -07:00
filemap.c mm,thp: avoid writes to file with THP in pagecache 2019-09-24 15:54:11 -07:00
frame_vector.c
frontswap.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482 2019-06-19 17:09:52 +02:00
gup_benchmark.c mm/gup: replace get_user_pages_longterm() with FOLL_LONGTERM 2019-05-14 09:47:45 -07:00
gup.c mm, thp: introduce FOLL_SPLIT_PMD 2019-09-24 15:54:11 -07:00
highmem.c mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
hmm.c pagewalk: separate function pointers from iterator data 2019-09-07 04:28:04 -03:00
huge_memory.c mm: thp: make deferred split shrinker memcg aware 2019-09-24 15:54:11 -07:00
hugetlb_cgroup.c mm: introduce compound_nr() 2019-09-24 15:54:08 -07:00
hugetlb.c hugetlbfs: don't retry when pool page allocations start to fail 2019-09-24 15:54:10 -07:00
hwpoison-inject.c hwpoison-inject: no need to check return value of debugfs_create functions 2019-06-03 15:39:40 +02:00
init-mm.c mm: use CPU_BITS_NONE to initialize init_mm.cpu_bitmask 2019-09-24 15:54:10 -07:00
internal.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
interval_tree.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 248 2019-06-19 17:09:08 +02:00
Kconfig mm,thp: add read-only THP support for (non-shmem) FS 2019-09-24 15:54:11 -07:00
Kconfig.debug mm, page_owner, debug_pagealloc: save and dump freeing stack trace 2019-09-24 15:54:08 -07:00
khugepaged.c khugepaged: enable collapse pmd for pte-mapped THP 2019-09-24 15:54:11 -07:00
kmemleak-test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
kmemleak.c mm/kmemleak.c: record the current memory pool size 2019-09-24 15:54:07 -07:00
ksm.c mm: move memcmp_pages() and pages_identical() 2019-09-24 15:54:11 -07:00
list_lru.c mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages 2019-07-12 11:05:44 -07:00
maccess.c The main changes in this release include: 2019-07-18 11:51:00 -07:00
madvise.c mm/madvise: reduce code duplication in error handling paths 2019-09-24 15:54:12 -07:00
Makefile mm: silence -Woverride-init/initializer-overrides 2019-09-24 15:54:10 -07:00
memblock.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
memcontrol.c mm: thp: make deferred split shrinker memcg aware 2019-09-24 15:54:11 -07:00
memfd.c mm: page cache: store only head pages in i_pages 2019-09-24 15:54:08 -07:00
memory_hotplug.c mm/memory_hotplug.c: s/is/if 2019-09-24 15:54:09 -07:00
memory-failure.c HMM patches for 5.3 2019-07-14 19:42:11 -07:00
memory.c mm: do not hash address in print_bad_pte() 2019-09-24 15:54:09 -07:00
mempolicy.c mm/mempolicy.c: remove unnecessary nodemask check in kernel_migrate_pages() 2019-09-24 15:54:10 -07:00
mempool.c docs/core-api/mm: fix return value descriptions in mm/ 2019-03-05 21:07:20 -08:00
memremap.c Merge branch 'odp_fixes' into hmm.git 2019-08-21 20:58:18 -03:00
memtest.c
migrate.c mm/migrate.c: clean up useless code in migrate_vma_collect_pmd() 2019-09-24 15:54:10 -07:00
mincore.c pagewalk: separate function pointers from iterator data 2019-09-07 04:28:04 -03:00
mlock.c mm/mlock.c: change count_mm_mlocked_page_nr return type 2019-06-13 17:34:56 -10:00
mm_init.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
mmap.c mm: mmap: increase sockets maximum memory size pgoff for 32bits 2019-09-24 15:54:12 -07:00
mmu_context.c
mmu_gather.c mm: remove quicklist page table caches 2019-09-24 15:54:09 -07:00
mmu_notifier.c mm, notifier: Catch sleeping/blocking for !blockable 2019-09-07 04:28:05 -03:00
mmzone.c
mprotect.c pagewalk: separate function pointers from iterator data 2019-09-07 04:28:04 -03:00
mremap.c mm/mmu_notifier: contextual information for event triggering invalidation 2019-05-14 09:47:49 -07:00
msync.c
nommu.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
oom_kill.c mm, oom: consider present pages for the node size 2019-09-24 15:54:10 -07:00
page_alloc.c mm: move mem_cgroup_uncharge out of __page_cache_release() 2019-09-24 15:54:11 -07:00
page_counter.c
page_ext.c mm, debug_pagealloc: use a page type instead of page_ext flag 2019-07-12 11:05:43 -07:00
page_idle.c mm/page_idle.c: fix oops because end_pfn is larger than max_pfn 2019-06-29 16:43:45 +08:00
page_io.c mm, swap: use rbtree for swap_extent 2019-07-12 11:05:43 -07:00
page_isolation.c mm/page_isolation.c: change the prototype of undo_isolate_page_range() 2019-07-12 11:05:43 -07:00
page_owner.c mm, page_owner, debug_pagealloc: save and dump freeing stack trace 2019-09-24 15:54:08 -07:00
page_poison.c mm/page_poison.c: fix a typo in a comment 2019-09-24 15:54:08 -07:00
page_vma_mapped.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
page-writeback.c writeback, memcg: Implement foreign dirty flushing 2019-08-27 09:22:38 -06:00
pagewalk.c pagewalk: use lockdep_assert_held for locking validation 2019-09-07 04:28:04 -03:00
percpu-internal.h percpu: convert chunk hints to be based on pcpu_block_md 2019-03-13 12:25:31 -07:00
percpu-km.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-stats.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-vm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu.c percpu: Use struct_size() helper 2019-09-04 13:40:49 -07:00
pgtable-generic.c x86/mm: Page size aware flush_tlb_mm_range() 2018-10-09 16:51:11 +02:00
process_vm_access.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
readahead.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
rmap.c mm,thp: add read-only THP support for (non-shmem) FS 2019-09-24 15:54:11 -07:00
rodata_test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441 2019-06-05 17:37:17 +02:00
shmem.c shmem: fix obsolete comment in shmem_getpage_gfp() 2019-09-24 15:54:12 -07:00
shuffle.c mm: maintain randomization of page free lists 2019-05-14 19:52:48 -07:00
shuffle.h mm: maintain randomization of page free lists 2019-05-14 19:52:48 -07:00
slab_common.c mm, slab: extend slab/shrink to shrink all memcg caches 2019-09-24 15:54:07 -07:00
slab.c mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options 2019-07-12 11:05:46 -07:00
slab.h mm, slab: move memcg_cache_params structure to mm/slab.h 2019-09-24 15:54:07 -07:00
slob.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
slub.c mm: introduce page_size() 2019-09-24 15:54:08 -07:00
sparse-vmemmap.c mm/sparsemem: convert kmalloc_section_memmap() to populate_section_memmap() 2019-07-18 17:08:07 -07:00
sparse.c mm/sparse.c: remove NULL check in clear_hwpoisoned_pages() 2019-09-24 15:54:09 -07:00
swap_cgroup.c
swap_slots.c
swap_state.c mm: page cache: store only head pages in i_pages 2019-09-24 15:54:08 -07:00
swap.c mm: move mem_cgroup_uncharge out of __page_cache_release() 2019-09-24 15:54:11 -07:00
swapfile.c vfs: don't allow writes to swap files 2019-08-20 07:55:16 -07:00
truncate.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
usercopy.c mm/usercopy: use memory range to be accessed for wraparound check 2019-08-13 16:06:52 -07:00
userfaultfd.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 2019-06-19 17:09:53 +02:00
util.c arm64, mm: make randomization selected by generic topdown mmap layout 2019-09-24 15:54:11 -07:00
vmacache.c mm: get rid of vmacache_flush_all() entirely 2018-09-13 15:18:04 -10:00
vmalloc.c mm/vmalloc.c: move 'area->pages' after if statement 2019-09-24 15:54:10 -07:00
vmpressure.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
vmscan.c mm: shrinker: make shrinker not depend on memcg kmem 2019-09-24 15:54:11 -07:00
vmstat.c mm,thp: stats for file backed THP 2019-09-24 15:54:11 -07:00
workingset.c mm: workingset: fix vmstat counters for shadow nodes 2019-08-13 16:06:52 -07:00
z3fold.c z3fold: fix memory leak in kmem cache 2019-09-24 15:54:10 -07:00
zbud.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
zpool.c zpool: add malloc_support_movable to zpool_driver 2019-09-24 15:54:12 -07:00
zsmalloc.c mm/zsmalloc.c: fix a -Wunused-function warning 2019-09-24 15:54:12 -07:00
zswap.c zswap: do not map same object twice 2019-09-24 15:54:12 -07:00