loop0: detected capacity change from 0 to 2048
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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237d25ea8 of 1 bytes by task 5959 on cpu 1:
 folio_batch_add include/linux/pagevec.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa5/0x1f0 mm/swap.c:510
 shmem_alloc_and_add_folio mm/shmem.c:2006 [inline]
 shmem_get_folio_gfp+0x7ab/0xd60 mm/shmem.c:2597
 shmem_get_folio mm/shmem.c:2703 [inline]
 shmem_write_begin+0xa8/0x190 mm/shmem.c:3353
 generic_perform_write+0x184/0x490 mm/filemap.c:4175
 shmem_file_write_iter+0xc5/0xf0 mm/shmem.c:3528
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x52a/0x960 fs/read_write.c:686
 ksys_write+0xda/0x1a0 fs/read_write.c:738
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:746
 x64_sys_call+0x27fe/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237d25ea8 of 1 bytes by task 5993 on cpu 0:
 folio_batch_count include/linux/pagevec.h:56 [inline]
 cpu_needs_drain mm/swap.c:778 [inline]
 __lru_add_drain_all+0x12b/0x3f0 mm/swap.c:872
 lru_add_drain_all+0x10/0x20 mm/swap.c:888
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 bdev_disk_changed+0xeb/0xcb0 block/partitions/core.c:657
 loop_reread_partitions drivers/block/loop.c:439 [inline]
 loop_set_status+0x541/0x5f0 drivers/block/loop.c:1265
 loop_set_status64 drivers/block/loop.c:1361 [inline]
 lo_ioctl+0x68f/0x1350 drivers/block/loop.c:1547
 blkdev_ioctl+0x34f/0x440 block/ioctl.c:705
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:598 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:584
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:584
 x64_sys_call+0x1816/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0d -> 0x10

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5993 Comm: syz.0.1216 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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