syzbot

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BUG: KCSAN: data-race in mlock_pagevec / need_mlock_page_drain

write to 0xffff888237d27ee0 of 1 bytes by task 5059 on cpu 1:
 pagevec_reinit include/linux/pagevec.h:46 [inline]
 mlock_pagevec+0x13a/0x150 mm/mlock.c:210
 munlock_page+0x25f/0x2a0 mm/mlock.c:304
 munlock_vma_page mm/internal.h:537 [inline]
 page_remove_rmap+0x17e/0x220 mm/rmap.c:1464
 try_to_migrate_one+0xa1a/0xe50 mm/rmap.c:2129
 rmap_walk_anon+0x3dc/0x5c0 mm/rmap.c:2451
 try_to_migrate+0x110/0x140
 __unmap_and_move mm/migrate.c:1107 [inline]
 unmap_and_move+0x62a/0x1010 mm/migrate.c:1184
 migrate_pages+0x2cb/0x8d0 mm/migrate.c:1461
 do_mbind+0x79b/0x8b0 mm/mempolicy.c:1337
 kernel_mbind mm/mempolicy.c:1484 [inline]
 __do_sys_mbind mm/mempolicy.c:1561 [inline]
 __se_sys_mbind+0x13b/0x3f0 mm/mempolicy.c:1557
 __x64_sys_mbind+0x74/0x80 mm/mempolicy.c:1557
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888237d27ee0 of 1 bytes by task 1814 on cpu 0:
 pagevec_count include/linux/pagevec.h:51 [inline]
 need_mlock_page_drain+0x2c/0x50 mm/mlock.c:236
 cpu_needs_drain mm/swap.c:822 [inline]
 __lru_add_drain_all+0x24e/0x3c0 mm/swap.c:910
 lru_add_drain_all+0xc/0x10 mm/swap.c:926
 invalidate_bdev+0x56/0x80 block/bdev.c:86
 ext4_put_super+0x510/0x810 fs/ext4/super.c:1273
 generic_shutdown_super+0xd5/0x240 fs/super.c:492
 kill_block_super+0x4a/0x90 fs/super.c:1428
 deactivate_locked_super+0x6a/0xb0 fs/super.c:332
 deactivate_super+0x85/0x90 fs/super.c:363
 cleanup_mnt+0x267/0x2d0 fs/namespace.c:1186
 __cleanup_mnt+0x15/0x20 fs/namespace.c:1193
 task_work_run+0xde/0x110 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x124/0x130 kernel/entry/common.c:171
 exit_to_user_mode_prepare kernel/entry/common.c:203 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:296
 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1814 Comm: syz-executor.5 Not tainted 6.1.0-rc5-syzkaller-00326-g77c51ba552a1-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
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