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BUG: KCSAN: data-race in __lru_add_drain_all / lru_cache_add

write to 0xffff888237c22528 of 1 bytes by task 4413 on cpu 0:
 pagevec_add include/linux/pagevec.h:74 [inline]
 pagevec_add_and_need_flush mm/swap.c:222 [inline]
 lru_cache_add+0x75/0x150 mm/swap.c:452
 shmem_getpage_gfp+0xca9/0x13c0 mm/shmem.c:1940
 shmem_getpage mm/shmem.c:151 [inline]
 shmem_fallocate+0x598/0x8b0 mm/shmem.c:2735
 vfs_fallocate+0x459/0x6a0 fs/open.c:307
 ksys_fallocate fs/open.c:330 [inline]
 __do_sys_fallocate fs/open.c:338 [inline]
 __se_sys_fallocate fs/open.c:336 [inline]
 __x64_sys_fallocate+0x75/0xc0 fs/open.c:336
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888237c22528 of 1 bytes by task 1041 on cpu 1:
 pagevec_count include/linux/pagevec.h:61 [inline]
 __lru_add_drain_all+0x12c/0x3e0 mm/swap.c:806
 lru_add_drain_all+0xc/0x10 mm/swap.c:828
 invalidate_bdev+0x56/0x80 fs/block_dev.c:97
 bdev_disk_changed+0xf6/0xe60 block/partitions/core.c:676
 blkdev_get_whole fs/block_dev.c:1092 [inline]
 blkdev_get_by_dev+0x6aa/0xca0 fs/block_dev.c:1234
 blkdev_reread_part block/ioctl.c:103 [inline]
 blkdev_common_ioctl+0x102a/0x10a0 block/ioctl.c:513
 blkdev_ioctl+0x16e/0x3e0 block/ioctl.c:583
 block_ioctl+0x6d/0x80 fs/block_dev.c:1421
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:860
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x08 -> 0x0f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1041 Comm: systemd-udevd Not tainted 5.14.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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