EXT4-fs (loop2): can't read group descriptor 0
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BUG: KCSAN: data-race in __lru_add_drain_all / folio_add_lru

read-write to 0xffff888237c26528 of 1 bytes by task 8925 on cpu 0:
 folio_batch_add include/linux/folio_batch.h:77 [inline]
 __folio_batch_add_and_move mm/swap.c:194 [inline]
 folio_add_lru+0xa4/0x1f0 mm/swap.c:517
 filemap_add_folio+0x267/0x350 mm/filemap.c:983
 __filemap_get_folio_mpol+0x32e/0x840 mm/filemap.c:2022
 __filemap_get_folio include/linux/pagemap.h:763 [inline]
 aio_setup_ring+0x262/0x710 fs/aio.c:577
 ioctx_alloc+0x296/0x480 fs/aio.c:845
 __do_sys_io_setup fs/aio.c:1452 [inline]
 __se_sys_io_setup+0x6b/0x1b0 fs/aio.c:1435
 __x64_sys_io_setup+0x31/0x40 fs/aio.c:1435
 x64_sys_call+0x24f1/0x3020 arch/x86/include/generated/asm/syscalls_64.h:207
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26528 of 1 bytes by task 8927 on cpu 1:
 folio_batch_count include/linux/folio_batch.h:56 [inline]
 cpu_needs_drain mm/swap.c:786 [inline]
 __lru_add_drain_all+0x17e/0x450 mm/swap.c:883
 lru_add_drain_all+0x10/0x20 mm/swap.c:899
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 __ext4_fill_super fs/ext4/super.c:5799 [inline]
 ext4_fill_super+0x2c9e/0x3780 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1634
 get_tree_bdev+0x1f/0x30 fs/super.c:1657
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5856
 vfs_get_tree+0x57/0x1d0 fs/super.c:1694
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3765 [inline]
 do_new_mount+0x288/0x8d0 fs/namespace.c:3841
 path_mount+0x4ad/0xb90 fs/namespace.c:4161
 do_mount fs/namespace.c:4174 [inline]
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4367
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4367
 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x02 -> 0x0c

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8927 Comm: syz.2.2605 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
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