syzbot

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BUG: KCSAN: data-race in lru_add_drain_all / lru_cache_add_inactive_or_unevictable

write to 0xffff888237d264a8 of 1 bytes by task 21890 on cpu 1:
 pagevec_add include/linux/pagevec.h:74 [inline]
 lru_cache_add mm/swap.c:461 [inline]
 lru_cache_add_inactive_or_unevictable+0xa9/0x250 mm/swap.c:493
 wp_page_copy+0x7f8/0x10c0 mm/memory.c:2953
 do_wp_page+0x5a8/0xba0 include/linux/spinlock_api_smp.h:152
 handle_pte_fault mm/memory.c:4385 [inline]
 __handle_mm_fault mm/memory.c:4502 [inline]
 handle_mm_fault+0xb31/0x1a70 mm/memory.c:4600
 do_user_addr_fault+0x60c/0xc00 arch/x86/mm/fault.c:1390
 handle_page_fault arch/x86/mm/fault.c:1475 [inline]
 exc_page_fault+0x94/0x230 arch/x86/mm/fault.c:1531
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:577

read to 0xffff888237d264a8 of 1 bytes by task 19152 on cpu 0:
 pagevec_count include/linux/pagevec.h:61 [inline]
 lru_add_drain_all+0x108/0x3b0 mm/swap.c:813
 invalidate_bdev+0x50/0x70 fs/block_dev.c:96
 ext4_put_super+0x5d0/0x8e0 fs/ext4/super.c:1230
 generic_shutdown_super+0xe1/0x230 fs/super.c:465
 kill_block_super+0x4a/0x90 fs/super.c:1395
 deactivate_locked_super+0x65/0xd0 fs/super.c:335
 deactivate_super+0x85/0x90 fs/super.c:366
 cleanup_mnt+0x267/0x2d0 fs/namespace.c:1136
 __cleanup_mnt+0x15/0x20 fs/namespace.c:1143
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301
 do_syscall_64+0x56/0x90 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 19152 Comm: syz-executor.5 Not tainted 5.12.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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