syzbot

EXT4-fs (loop4): unmounting filesystem.
==================================================================
BUG: KCSAN: data-race in __lru_add_drain_all / folio_activate

read-write to 0xffff888237c27b88 of 1 bytes by task 2250 on cpu 0:
 folio_batch_add include/linux/pagevec.h:129 [inline]
 folio_batch_add_and_move mm/swap.c:260 [inline]
 folio_activate+0xce/0x1c0 mm/swap.c:378
 folio_mark_accessed+0x138/0x1a0 mm/swap.c:498
 shmem_file_read_iter+0x31d/0x580 mm/shmem.c:2659
 call_read_iter include/linux/fs.h:2185 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3a5/0x560 fs/read_write.c:470
 ksys_read+0xe8/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:621
 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 0xffff888237c27b88 of 1 bytes by task 1843 on cpu 1:
 folio_batch_count include/linux/pagevec.h:108 [inline]
 cpu_needs_drain mm/swap.c:821 [inline]
 __lru_add_drain_all+0x22a/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: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1843 Comm: syz-executor.4 Tainted: G        W          6.1.0-rc2-syzkaller-00487-gb72018ab8236-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
==================================================================
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.
EXT4-fs (loop4): unmounting filesystem.