Guo Ziliang 029c4628b2 mm: swap: get rid of livelock in swapin readahead ... In our testing, a livelock task was found. Through sysrq printing, same stack was found every time, as follows: __swap_duplicate+0x58/0x1a0 swapcache_prepare+0x24/0x30 __read_swap_cache_async+0xac/0x220 read_swap_cache_async+0x58/0xa0 swapin_readahead+0x24c/0x628 do_swap_page+0x374/0x8a0 __handle_mm_fault+0x598/0xd60 handle_mm_fault+0x114/0x200 do_page_fault+0x148/0x4d0 do_translation_fault+0xb0/0xd4 do_mem_abort+0x50/0xb0 The reason for the livelock is that swapcache_prepare() always returns EEXIST, indicating that SWAP_HAS_CACHE has not been cleared, so that it cannot jump out of the loop. We suspect that the task that clears the SWAP_HAS_CACHE flag never gets a chance to run. We try to lower the priority of the task stuck in a livelock so that the task that clears the SWAP_HAS_CACHE flag will run. The results show that the system returns to normal after the priority is lowered. In our testing, multiple real-time tasks are bound to the same core, and the task in the livelock is the highest priority task of the core, so the livelocked task cannot be preempted. Although cond_resched() is used by __read_swap_cache_async, it is an empty function in the preemptive system and cannot achieve the purpose of releasing the CPU. A high-priority task cannot release the CPU unless preempted by a higher-priority task. But when this task is already the highest priority task on this core, other tasks will not be able to be scheduled. So we think we should replace cond_resched() with schedule_timeout_uninterruptible(1), schedule_timeout_interruptible will call set_current_state first to set the task state, so the task will be removed from the running queue, so as to achieve the purpose of giving up the CPU and prevent it from running in kernel mode for too long. (akpm: ugly hack becomes uglier. But it fixes the issue in a backportable-to-stable fashion while we hopefully work on something better) Link: https://lkml.kernel.org/r/20220221111749.1928222-1-cgel.zte@gmail.com Signed-off-by: Guo Ziliang <guo.ziliang@zte.com.cn> Reported-by: Zeal Robot <zealci@zte.com.cn> Reviewed-by: Ran Xiaokai <ran.xiaokai@zte.com.cn> Reviewed-by: Jiang Xuexin <jiang.xuexin@zte.com.cn> Reviewed-by: Yang Yang <yang.yang29@zte.com.cn> Acked-by: Hugh Dickins <hughd@google.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Roger Quadros <rogerq@kernel.org> Cc: Ziliang Guo <guo.ziliang@zte.com.cn> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2022-03-17 11:02:13 -07:00
..
damon	mm/damon: hide kernel pointer from tracepoint event	2022-01-15 16:30:33 +02:00
kasan	lib/stackdepot: always do filter_irq_stacks() in stack_depot_save()	2022-01-22 08:33:38 +02:00
kfence	kfence: make test case compatible with run time set sample interval	2022-02-11 17:55:00 -08:00
backing-dev.c	mm: bdi: initialize bdi_min_ratio when bdi is unregistered	2021-12-10 17:10:56 -08:00
balloon_compaction.c	mm: fix typos in comments	2021-05-07 00:26:35 -07:00
bootmem_info.c	bootmem: Use page->index instead of page->freelist	2022-01-06 12:27:03 +01:00
cma_debug.c	mm/cma: change cma mutex to irq safe spinlock	2021-05-05 11:27:21 -07:00
cma_sysfs.c	mm: cma: support sysfs	2021-05-05 11:27:24 -07:00
cma.c	memblock: rename memblock_free to memblock_phys_free	2021-11-06 13:30:41 -07:00
cma.h	mm: cma: support sysfs	2021-05-05 11:27:24 -07:00
compaction.c	mm: compaction: fix the migration stats in trace_mm_compaction_migratepages()	2022-01-15 16:30:30 +02:00
debug_page_ref.c
debug_vm_pgtable.c	mm/debug_vm_pgtable: remove pte entry from the page table	2022-02-04 09:25:04 -08:00
debug.c	mm,fs: split dump_mapping() out from dump_page()	2022-01-15 16:30:26 +02:00
dmapool.c	mm/dmapool.c: revert "make dma pool to use kmalloc_node"	2022-01-15 16:30:28 +02:00
early_ioremap.c	mm/early_ioremap.c: remove redundant early_ioremap_shutdown()	2021-09-08 11:50:24 -07:00
fadvise.c
failslab.c
filemap.c	Merge branch 'akpm' (patches from Andrew)	2022-01-22 11:28:23 +02:00
folio-compat.c	filemap: Add filemap_release_folio()	2022-01-04 13:15:34 -05:00
frontswap.c	frontswap: remove support for multiple ops	2022-01-22 08:33:38 +02:00
gup_test.c	selftests/vm: gup_test: test faulting in kernel, and verify pinnable pages	2021-05-05 11:27:26 -07:00
gup_test.h	selftests/vm: gup_test: fix test flag	2021-05-05 11:27:26 -07:00
gup.c	mm: gup: make fault_in_safe_writeable() use fixup_user_fault()	2022-03-10 10:48:53 -08:00
highmem.c	Fixes for 5.16 folios:	2021-11-25 10:13:56 -08:00
hmm.c	mm/hmm.c: allow VM_MIXEDMAP to work with hmm_range_fault	2022-01-15 16:30:31 +02:00
huge_memory.c	Merge branch 'akpm' (patches from Andrew)	2022-01-15 20:37:06 +02:00
hugetlb_cgroup.c	hugetlb: add hugetlb.*.numa_stat file	2022-01-15 16:30:29 +02:00
hugetlb_vmemmap.c	mm: hugetlb: introduce CONFIG_HUGETLB_PAGE_FREE_VMEMMAP_DEFAULT_ON	2021-06-30 20:47:26 -07:00
hugetlb_vmemmap.h	mm: hugetlb: introduce nr_free_vmemmap_pages in the struct hstate	2021-06-30 20:47:25 -07:00
hugetlb.c	hugetlbfs: fix a truncation issue in hugepages parameter	2022-02-26 09:51:17 -08:00
hwpoison-inject.c	mm: hwpoison: don't drop slab caches for offlining non-LRU page	2021-09-03 09:58:15 -07:00
init-mm.c	mm: add setup_initial_init_mm() helper	2021-07-08 11:48:21 -07:00
internal.h	Merge branch 'akpm' (patches from Andrew)	2022-01-15 20:37:06 +02:00
interval_tree.c	mm/interval_tree: add comments to improve code readability	2021-04-30 11:20:38 -07:00
io-mapping.c	mm: add a io_mapping_map_user helper	2021-04-30 11:20:39 -07:00
ioremap.c	mm: move ioremap_page_range to vmalloc.c	2021-09-08 11:50:24 -07:00
Kconfig	mm: hide the FRONTSWAP Kconfig symbol	2022-01-22 08:33:38 +02:00
Kconfig.debug	mm: page table check	2022-01-15 16:30:28 +02:00
khugepaged.c	mm/page_table_check: check entries at pmd levels	2022-02-04 09:25:04 -08:00
kmemleak.c	mm/kmemleak: avoid scanning potential huge holes	2022-02-04 09:25:05 -08:00
ksm.c	mm: ksm: fix use-after-free kasan report in ksm_might_need_to_copy	2022-01-15 16:30:31 +02:00
list_lru.c	mm: list_lru: only add memcg-aware lrus to the global lru list	2021-11-06 13:30:35 -07:00
maccess.c	ARM: 9115/1: mm/maccess: fix unaligned copy_{from,to}_kernel_nofault	2021-08-20 11:39:25 +01:00
madvise.c	mm: fix use-after-free when anon vma name is used after vma is freed	2022-03-05 11:08:32 -08:00
Makefile	mm: remove cleancache	2022-01-22 08:33:38 +02:00
mapping_dirty_helpers.c	mm: move tlb_flush_pending inline helpers to mm_inline.h	2022-01-15 16:30:27 +02:00
memblock.c	memblock: use kfree() to release kmalloced memblock regions	2022-02-20 08:45:39 +02:00
memcontrol.c	mm: memcg: synchronize objcg lists with a dedicated spinlock	2022-02-11 17:55:00 -08:00
memfd.c	memfd: fix F_SEAL_WRITE after shmem huge page allocated	2022-03-05 11:08:32 -08:00
memory_hotplug.c	treewide: Add missing includes masked by cgroup -> bpf dependency	2021-12-03 10:58:13 -08:00
memory-failure.c	memory-failure: fetch compound_head after pgmap_pfn_valid()	2022-01-30 09:56:58 +02:00
memory.c	Merge branch 'akpm' (patches from Andrew)	2022-01-20 10:41:01 +02:00
mempolicy.c	mm: refactor vm_area_struct::anon_vma_name usage code	2022-03-05 11:08:32 -08:00
mempool.c	mm: remove spurious blkdev.h includes	2021-10-18 06:17:01 -06:00
memremap.c	Merge branch 'akpm' (patches from Andrew)	2022-01-15 20:37:06 +02:00
memtest.c
migrate.c	mm/migrate.c: rework migration_entry_wait() to not take a pageref	2022-01-22 08:33:34 +02:00
mincore.c
mlock.c	mm: refactor vm_area_struct::anon_vma_name usage code	2022-03-05 11:08:32 -08:00
mm_init.c	include/linux/page-flags-layout.h: cleanups	2021-04-30 11:20:42 -07:00
mmap_lock.c	mm: mmap_lock: fix disabling preemption directly	2021-07-23 17:43:28 -07:00
mmap.c	mm: refactor vm_area_struct::anon_vma_name usage code	2022-03-05 11:08:32 -08:00
mmu_gather.c	mm: move tlb_flush_pending inline helpers to mm_inline.h	2022-01-15 16:30:27 +02:00
mmu_notifier.c	mm/mmu_notifiers: ensure range_end() is paired with range_start()	2021-03-25 09:22:55 -07:00
mmzone.c
mprotect.c	mm: refactor vm_area_struct::anon_vma_name usage code	2022-03-05 11:08:32 -08:00
mremap.c	mm, hugepages: add mremap() support for hugepage backed vma	2021-11-06 13:30:39 -07:00
msync.c	mm/msync: exit early when the flags is an MS_ASYNC and start < vm_start	2021-04-30 11:20:37 -07:00
nommu.c	Merge branch 'akpm' (patches from Andrew)	2021-11-06 14:08:17 -07:00
oom_kill.c	Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2022-01-17 05:49:30 +02:00
page_alloc.c	Merge branch 'akpm' (patches from Andrew)	2022-01-20 10:41:01 +02:00
page_counter.c	mm/page_counter: remove an incorrect call to propagate_protected_usage()	2022-01-15 16:30:27 +02:00
page_ext.c	mm: make some vars and functions static or __init	2022-01-15 16:30:31 +02:00
page_idle.c	mm/idle_page_tracking: make PG_idle reusable	2021-09-08 11:50:24 -07:00
page_io.c	delayacct: support swapin delay accounting for swapping without blkio	2022-01-20 08:52:55 +02:00
page_isolation.c	Revert "mm/page_isolation: unset migratetype directly for non Buddy page"	2022-02-04 09:25:04 -08:00
page_owner.c	lib/stackdepot: allow optional init and stack_table allocation by kvmalloc()	2022-01-22 08:33:37 +02:00
page_poison.c	mm: page_poison: print page info when corruption is caught	2021-04-30 11:20:36 -07:00
page_reporting.c	mm/page_reporting: allow driver to specify reporting order	2021-06-29 10:53:47 -07:00
page_reporting.h	mm/page_reporting: export reporting order as module parameter	2021-06-29 10:53:47 -07:00
page_table_check.c	mm/page_table_check: check entries at pmd levels	2022-02-04 09:25:04 -08:00
page_vma_mapped.c	mm: device exclusive memory access	2021-07-01 11:06:03 -07:00
page-writeback.c	mm/writeback: Improve __folio_mark_dirty() comment	2022-01-02 20:28:57 -05:00
pagewalk.c	mm: pagewalk: fix walk for hugepage tables	2021-06-29 10:53:49 -07:00
percpu-internal.h	mm: memcg/percpu: account extra objcg space to memory cgroups	2022-01-15 16:30:31 +02:00
percpu-km.c	percpu: flush tlb in pcpu_reclaim_populated()	2021-07-04 18:30:17 +00:00
percpu-stats.c	percpu: rework memcg accounting	2021-06-05 20:43:15 +00:00
percpu-vm.c	percpu: flush tlb in pcpu_reclaim_populated()	2021-07-04 18:30:17 +00:00
percpu.c	bitmap patches for 5.17-rc1	2022-01-23 06:20:44 +02:00
pgalloc-track.h	mm: fix typos in comments	2021-05-07 00:26:35 -07:00
pgtable-generic.c	mm: move tlb_flush_pending inline helpers to mm_inline.h	2022-01-15 16:30:27 +02:00
process_vm_access.c	mm/process_vm_access.c: remove duplicate include	2021-05-05 11:27:27 -07:00
ptdump.c	mm: ptdump: fix build failure	2021-04-16 16:10:37 -07:00
readahead.c	readahead: Convert page_cache_ra_unbounded to folios	2022-01-04 13:15:34 -05:00
rmap.c	mm/rmap: fix potential batched TLB flush race	2022-01-15 16:30:31 +02:00
rodata_test.c
secretmem.c	mm/secretmem: avoid letting secretmem_users drop to zero	2021-10-28 17:18:55 -07:00
shmem.c	mm: simplify try_to_unuse	2022-01-22 08:33:38 +02:00
shuffle.c	mm: eliminate "expecting prototype" kernel-doc warnings	2021-04-16 16:10:36 -07:00
shuffle.h	mm/shuffle: fix section mismatch warning	2021-05-22 15:09:07 -10:00
slab_common.c	Merge branch 'akpm' (patches from Andrew)	2022-01-15 20:37:06 +02:00
slab.c	mm/kasan: Convert to struct folio and struct slab	2022-01-06 12:26:14 +01:00
slab.h	slab changes for 5.17 - part 2	2022-01-18 06:40:47 +02:00
slob.c	mm/slob: Remove unnecessary page_mapcount_reset() function call	2022-01-06 12:27:28 +01:00
slub.c	mm/slub: Define struct slab fields for CONFIG_SLUB_CPU_PARTIAL only when enabled	2022-01-06 12:26:53 +01:00
sparse-vmemmap.c	mm: remove redundant smp_wmb()	2021-11-06 13:30:36 -07:00
sparse.c	bootmem: Use page->index instead of page->freelist	2022-01-06 12:27:03 +01:00
swap_cgroup.c
swap_slots.c	treewide: Add missing includes masked by cgroup -> bpf dependency	2021-12-03 10:58:13 -08:00
swap_state.c	mm: swap: get rid of livelock in swapin readahead	2022-03-17 11:02:13 -07:00
swap.c	Merge branch 'akpm' (patches from Andrew)	2022-01-15 20:37:06 +02:00
swapfile.c	mm: mark swap_lock and swap_active_head static	2022-01-22 08:33:38 +02:00
truncate.c	mm: remove cleancache	2022-01-22 08:33:38 +02:00
usercopy.c	mm: Convert check_heap_object() to use struct slab	2022-01-06 12:25:51 +01:00
userfaultfd.c	mm: shmem: don't truncate page if memory failure happens	2022-01-15 16:30:26 +02:00
util.c	mm: Consider __GFP_NOWARN flag for oversized kvmalloc() calls	2022-03-04 10:00:37 -08:00
vmacache.c
vmalloc.c	mm/vmalloc: be more explicit about supported gfp flags.	2022-01-15 16:30:28 +02:00
vmpressure.c	mm/vmpressure: fix data-race with memcg->socket_pressure	2021-11-06 13:30:40 -07:00
vmscan.c	mm: vmscan: remove deadlock due to throttling failing to make progress	2022-02-11 17:55:00 -08:00
vmstat.c	mm/vmstat: add events for THP max_ptes_* exceeds	2022-01-15 16:30:29 +02:00
workingset.c	Merge branch 'akpm' (patches from Andrew)	2021-11-09 10:11:53 -08:00
z3fold.c	mm/z3fold: add kerneldoc fields for z3fold_pool	2021-07-01 11:06:03 -07:00
zbud.c	mm/zbud: add kerneldoc fields for zbud_pool	2021-07-01 11:06:03 -07:00
zpool.c	zpool: remove the list of pools_head	2022-01-15 16:30:31 +02:00
zsmalloc.c	zsmalloc: replace get_cpu_var with local_lock	2022-01-22 08:33:37 +02:00
zswap.c	frontswap: remove support for multiple ops	2022-01-22 08:33:38 +02:00