Guo Ziliang 6829aa17ca mm: swap: get rid of livelock in swapin readahead ... commit 029c4628b2 upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-03-23 09:16:41 +01:00
..
damon	mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()'	2022-01-05 12:42:39 +01:00
kasan	kasan: fix quarantine conflicting with init_on_free	2022-03-08 19:12:38 +01:00
kfence	kfence: fix memory leak when cat kfence objects	2021-12-29 12:29:00 +01:00
backing-dev.c	mm: bdi: initialize bdi_min_ratio when bdi is unregistered	2021-12-14 10:57:11 +01:00
balloon_compaction.c	mm: fix typos in comments	2021-05-07 00:26:35 -07:00
bootmem_info.c	mm/bootmem_info.c: mark __init on register_page_bootmem_info_section	2021-09-03 09:58:14 -07:00
cleancache.c
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	mm: use proper type for cma_[alloc|release]	2021-05-05 11:27:24 -07:00
cma.h	mm: cma: support sysfs	2021-05-05 11:27:24 -07:00
compaction.c	Merge branch 'akpm' (patches from Andrew)	2021-09-08 12:55:35 -07:00
debug_page_ref.c
debug_vm_pgtable.c	mm/debug_vm_pgtable: remove pte entry from the page table	2022-02-08 18:34:05 +01:00
debug.c	mm/debug: sync up latest migrate_reason to migrate_reason_names	2021-09-24 16:13:35 -07:00
dmapool.c	mm/dmapool: use DEVICE_ATTR_RO macro	2021-06-29 10:53:52 -07:00
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	mm/filemap: Fix handling of THPs in generic_file_buffered_read()	2022-03-02 11:47:47 +01:00
frontswap.c	mm/mempool: minor coding style tweaks	2021-05-05 11:27:27 -07:00
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	Revert "mm/gup: small refactoring: simplify try_grab_page()"	2022-02-05 12:38:57 +01:00
highmem.c	kmap_local: don't assume kmap PTEs are linear arrays in memory	2021-11-25 09:48:43 +01:00
hmm.c	mm/hmm.c: allow VM_MIXEDMAP to work with hmm_range_fault	2022-01-27 11:05:43 +01:00
huge_memory.c	mm: filemap: check if THP has hwpoisoned subpage for PMD page fault	2021-10-28 17:18:55 -07:00
hugetlb_cgroup.c	hugetlb: make free_huge_page irq safe	2021-05-05 11:27:22 -07:00
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: flush TLBs correctly after huge_pmd_unshare	2021-11-25 09:49:07 +01:00
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	mm/numa: automatically generate node migration order	2021-09-03 09:58:16 -07:00
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	kmap_local: don't assume kmap PTEs are linear arrays in memory	2021-11-25 09:48:43 +01:00
Kconfig.debug	mm, page_poison: remove CONFIG_PAGE_POISONING_ZERO	2020-12-15 12:13:46 -08:00
khugepaged.c	mm: khugepaged: skip huge page collapse for special files	2021-10-28 17:18:55 -07:00
kmemleak.c	mm/kmemleak: avoid scanning potential huge holes	2022-02-08 18:34:05 +01:00
ksm.c	mm/ksm: remove old GCC 4.9+ check	2021-09-13 10:18:28 -07:00
list_lru.c	mm: vmscan: consolidate shrinker_maps handling code	2021-05-05 11:27:23 -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	Merge branch 'akpm' (patches from Andrew)	2021-09-03 10:08:28 -07:00
Makefile	mm: introduce Data Access MONitor (DAMON)	2021-09-08 11:50:24 -07:00
mapping_dirty_helpers.c	mm/mapping_dirty_helpers: remove double Note in kerneldoc	2021-07-01 11:06:02 -07:00
memblock.c	memblock: use kfree() to release kmalloced memblock regions	2022-03-02 11:48:10 +01:00
memcontrol.c	mm: memcg: synchronize objcg lists with a dedicated spinlock	2022-02-16 12:56:38 +01:00
memfd.c	memfd: fix F_SEAL_WRITE after shmem huge page allocated	2022-03-08 19:12:48 +01:00
memory_hotplug.c	Merge branch 'akpm' (patches from Andrew)	2021-09-08 12:55:35 -07:00
memory-failure.c	mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page()	2021-12-29 12:28:58 +01:00
memory.c	mm: filemap: check if THP has hwpoisoned subpage for PMD page fault	2021-10-28 17:18:55 -07:00
mempolicy.c	mm: mempolicy: fix THP allocations escaping mempolicy restrictions	2021-12-29 12:28:58 +01:00
mempool.c	kasan: use separate (un)poison implementation for integrated init	2021-06-04 19:32:21 +01:00
memremap.c	mm/memory_hotplug: remove nid parameter from arch_remove_memory()	2021-09-08 11:50:23 -07:00
memtest.c
migrate.c	mm/migrate: fix CPUHP state to update node demotion order	2021-10-18 20:22:03 -10:00
mincore.c	inode: make init and permission helpers idmapped mount aware	2021-01-24 14:27:16 +01:00
mlock.c	mm: introduce memfd_secret system call to create "secret" memory areas	2021-07-08 11:48:21 -07:00
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	Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux	2021-09-04 11:35:47 -07:00
mmu_gather.c	mm: eliminate "expecting prototype" kernel-doc warnings	2021-04-16 16:10:36 -07:00
mmu_notifier.c	mm/mmu_notifiers: ensure range_end() is paired with range_start()	2021-03-25 09:22:55 -07:00
mmzone.c	mm/lru: replace pgdat lru_lock with lruvec lock	2020-12-15 14:48:04 -08:00
mprotect.c	mm: don't try to NUMA-migrate COW pages that have other uses	2022-02-23 12:03:03 +01:00
mremap.c	mm/mremap: fix memory account on do_munmap() failure	2021-09-03 09:58:14 -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 tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux	2021-09-04 11:35:47 -07:00
oom_kill.c	mm, oom: do not trigger out_of_memory from the #PF	2021-11-18 19:17:16 +01:00
page_alloc.c	mm/page_alloc.c: do not warn allocation failure on zone DMA if no managed pages	2022-01-27 11:03:00 +01:00
page_counter.c	mm: page_counter: mitigate consequences of a page_counter underflow	2021-04-30 11:20:38 -07:00
page_ext.c	mm/migrate: add CPU hotplug to demotion #ifdef	2021-10-18 20:22:02 -10:00
page_idle.c	mm/idle_page_tracking: make PG_idle reusable	2021-09-08 11:50:24 -07:00
page_io.c	swap: fix swapfile read/write offset	2021-03-02 17:25:46 -07:00
page_isolation.c	Merge branch 'akpm' (patches from Andrew)	2021-09-08 12:55:35 -07:00
page_owner.c	mm: remove pfn_valid_within() and CONFIG_HOLES_IN_ZONE	2021-09-08 11:50:22 -07:00
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_vma_mapped.c	mm: device exclusive memory access	2021-07-01 11:06:03 -07:00
page-writeback.c	Merge branch 'akpm' (patches from Andrew)	2021-09-03 10:08:28 -07:00
pagewalk.c	mm: pagewalk: fix walk for hugepage tables	2021-06-29 10:53:49 -07:00
percpu-internal.h	Merge branch 'for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu	2021-07-01 17:17:24 -07:00
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	Merge branch 'akpm' (patches from Andrew)	2021-09-08 12:55:35 -07:00
pgalloc-track.h	mm: fix typos in comments	2021-05-07 00:26:35 -07:00
pgtable-generic.c	mm/thp: fix __split_huge_pmd_locked() on shmem migration entry	2021-06-16 09:24:42 -07:00
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	mm: Protect operations adding pages to page cache with invalidate_lock	2021-07-13 13:14:27 +02:00
rmap.c	Merge branch 'akpm' (patches from Andrew)	2021-09-08 12:55:35 -07:00
rodata_test.c
secretmem.c	mm/secretmem: avoid letting secretmem_users drop to zero	2021-10-28 17:18:55 -07:00
shmem.c	shmem: fix a race between shmem_unused_huge_shrink and shmem_evict_inode	2022-01-27 11:03:01 +01:00
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	mm: slub: move flush_cpu_slab() invocations __free_slab() invocations out of IRQ context	2021-09-04 01:12:23 +02:00
slab.c	mm/migrate: add CPU hotplug to demotion #ifdef	2021-10-18 20:22:02 -10:00
slab.h	mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag	2021-11-25 09:48:42 +01:00
slob.c	mm: Don't build mm_dump_obj() on CONFIG_PRINTK=n kernels	2021-03-08 14:18:46 -08:00
slub.c	mm/slub: fix endianness bug for alloc/free_traces attributes	2021-12-14 10:57:11 +01:00
sparse-vmemmap.c	mm: sparsemem: split the huge PMD mapping of vmemmap pages	2021-06-30 20:47:26 -07:00
sparse.c	mm: introduce memmap_alloc() to unify memory map allocation	2021-09-03 09:58:15 -07:00
swap_cgroup.c
swap_slots.c	mm: Replace deprecated CPU-hotplug functions.	2021-08-28 01:46:17 +02:00
swap_state.c	mm: swap: get rid of livelock in swapin readahead	2022-03-23 09:16:41 +01:00
swap.c	mm: fs: invalidate bh_lrus for only cold path	2021-09-24 16:13:35 -07:00
swapfile.c	mm, memcg: inline swap-related functions to improve disabled memcg config	2021-09-03 09:58:12 -07:00
truncate.c	Merge branch 'akpm' (patches from Andrew)	2021-09-03 10:08:28 -07:00
usercopy.c
userfaultfd.c	userfaultfd: change mmap_changing to atomic	2021-09-03 09:58:16 -07:00
util.c	mm: Consider __GFP_NOWARN flag for oversized kvmalloc() calls	2022-03-08 19:12:44 +01:00
vmacache.c
vmalloc.c	mm: defer kmemleak object creation of module_alloc()	2022-03-08 19:12:38 +01:00
vmpressure.c	mm/vmpressure: replace vmpressure_to_css() with vmpressure_to_memcg()	2021-09-03 09:58:17 -07:00
vmscan.c	mm,vmscan: fix divide by zero in get_scan_count	2021-09-08 18:45:53 -07:00
vmstat.c	mm/vmstat: protect per cpu variables with preempt disable on RT	2021-09-08 15:32:34 -07:00
workingset.c	memcg: flush lruvec stats in the refault	2021-09-23 10:09:13 -07:00
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	mm: fix typos in comments	2021-05-07 00:26:35 -07:00
zsmalloc.c	mm/zsmalloc.c: close race window between zs_pool_dec_isolated() and zs_unregister_migration()	2021-11-18 19:17:10 +01:00
zswap.c	mm/zswap.c: fix two bugs in zswap_writeback_entry()	2021-06-30 20:47:31 -07:00