================================================================== BUG: KCSAN: data-race in blkdev_open / queue_limits_commit_update read to 0xffff888102208bb0 of 4 bytes by task 17244 on cpu 1: bdev_can_atomic_write include/linux/blkdev.h:1855 [inline] blkdev_open+0x161/0x290 block/fops.c:692 do_dentry_open+0x4be/0xa90 fs/open.c:947 vfs_open+0x37/0x1e0 fs/open.c:1079 do_open fs/namei.c:4699 [inline] path_openat+0x1b70/0x2050 fs/namei.c:4858 do_file_open+0x16c/0x290 fs/namei.c:4887 do_sys_openat2+0x94/0x130 fs/open.c:1364 do_sys_open fs/open.c:1370 [inline] __do_sys_openat fs/open.c:1386 [inline] __se_sys_openat fs/open.c:1381 [inline] __x64_sys_openat+0xf2/0x120 fs/open.c:1381 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/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f write to 0xffff888102208b20 of 192 bytes by task 20340 on cpu 0: queue_limits_commit_update+0x4b/0x160 block/blk-settings.c:564 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:797 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/0x3b0 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: 20340 Comm: syz.7.7348 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 ================================================================== loop7: detected capacity change from 0 to 128 FAT-fs (loop7): utf8 is not a recommended IO charset for FAT filesystems, filesystem will be case sensitive! FAT-fs (loop7): Invalid FSINFO signature: 0x41615252, 0x80417272 (sector = 1) FAT-fs (loop7): error, fat_get_cluster: invalid cluster chain (i_pos 0) FAT-fs (loop7): Filesystem has been set read-only