================================================================== BUG: KCSAN: data-race in blkdev_open / queue_limits_commit_update read to 0xffff8881021897b0 of 4 bytes by task 3304 on cpu 0: 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 0xffff888102189720 of 192 bytes by task 7461 on cpu 1: queue_limits_commit_update+0x4b/0x160 block/blk-settings.c:577 loop_configure+0x78c/0x9c0 drivers/block/loop.c:1064 lo_ioctl+0x1e1/0x13a0 drivers/block/loop.c:1534 blkdev_ioctl+0x387/0x460 block/ioctl.c:804 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583 x64_sys_call+0x1563/0x3020 arch/x86/include/generated/asm/syscalls_64.h:17 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: 1 UID: 0 PID: 7461 Comm: syz.5.884 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 ================================================================== loop5: detected capacity change from 0 to 512 EXT4-fs: Ignoring removed nobh option EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support! EXT4-fs (loop5): encrypted files will use data=ordered instead of data journaling mode EXT4-fs (loop5): 1 truncate cleaned up EXT4-fs (loop5): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.