syzbot

loop1: detected capacity change from 0 to 512
EXT4-fs (loop1): SIPHASH is not a valid default hash value
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BUG: KCSAN: data-race in blkdev_open / queue_limits_commit_update

read to 0xffff8881023da6d0 of 4 bytes by task 4275 on cpu 1:
 bdev_can_atomic_write include/linux/blkdev.h:1847 [inline]
 blkdev_open+0x161/0x290 block/fops.c:692
 do_dentry_open+0x4ca/0xa90 fs/open.c:949
 vfs_open+0x37/0x1e0 fs/open.c:1081
 do_open fs/namei.c:4671 [inline]
 path_openat+0x1b70/0x2050 fs/namei.c:4830
 do_file_open+0x16c/0x290 fs/namei.c:4859
 do_sys_openat2+0x94/0x130 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_openat fs/open.c:1388 [inline]
 __se_sys_openat fs/open.c:1383 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1383
 x64_sys_call+0x1e39/0x3020 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff8881023da640 of 192 bytes by task 4346 on cpu 0:
 queue_limits_commit_update+0x4b/0x160 block/blk-settings.c:577
 __loop_clr_fd drivers/block/loop.c:1141 [inline]
 lo_release+0x209/0x420 drivers/block/loop.c:1751
 bdev_release+0x373/0x3d0 block/bdev.c:-1
 blkdev_release+0x15/0x20 block/fops.c:705
 __fput+0x29b/0x650 fs/file_table.c:469
 fput_close_sync+0xad/0x190 fs/file_table.c:574
 __do_sys_close fs/open.c:1509 [inline]
 __se_sys_close fs/open.c:1494 [inline]
 __x64_sys_close+0x55/0xf0 fs/open.c:1494
 x64_sys_call+0x275d/0x3020 arch/x86/include/generated/asm/syscalls_64.h:4
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4346 Comm: syz.1.244 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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