udevd[3301]: inotify_add_watch(7, /dev/loop1p4, 10) failed: No such file or directory
==================================================================
BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff893980c8 of 1 bytes by task 4002 on cpu 1:
 string_nocheck lib/vsprintf.c:659 [inline]
 string+0x187/0x220 lib/vsprintf.c:737
 vsnprintf+0x532/0x860 lib/vsprintf.c:2948
 vscnprintf+0x41/0x90 lib/vsprintf.c:3013
 printk_sprint+0x30/0x2e0 kernel/printk/printk.c:2222
 vprintk_store+0x57b/0x910 kernel/printk/printk.c:2364
 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455
 devkmsg_emit+0x7f/0xb0 kernel/printk/printk.c:733
 devkmsg_write+0x1e2/0x2b0 kernel/printk/printk.c:796
 do_iter_readv_writev+0x4fd/0x5a0 fs/read_write.c:-1
 vfs_writev+0x2e1/0x900 fs/read_write.c:1059
 do_writev+0xe9/0x210 fs/read_write.c:1105
 __do_sys_writev fs/read_write.c:1173 [inline]
 __se_sys_writev fs/read_write.c:1170 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1170
 x64_sys_call+0x1c0c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:21
 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

read to 0xffffffff893980c8 of 8 bytes by task 3301 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:608 [inline]
 data_push_tail+0x100/0x470 kernel/printk/printk_ringbuffer.c:693
 data_alloc+0x11b/0x390 kernel/printk/printk_ringbuffer.c:1089
 prb_reserve+0x8d7/0xae0 kernel/printk/printk_ringbuffer.c:1724
 vprintk_store+0x54a/0x910 kernel/printk/printk.c:2354
 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455
 devkmsg_emit+0x7f/0xb0 kernel/printk/printk.c:733
 devkmsg_write+0x1e2/0x2b0 kernel/printk/printk.c:796
 do_iter_readv_writev+0x4fd/0x5a0 fs/read_write.c:-1
 vfs_writev+0x2e1/0x900 fs/read_write.c:1059
 do_writev+0xe9/0x210 fs/read_write.c:1105
 __do_sys_writev fs/read_write.c:1173 [inline]
 __se_sys_writev fs/read_write.c:1170 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1170
 x64_sys_call+0x1c0c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:21
 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

value changed: 0x00000000ffffefed -> 0x00000a79726f7463

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3301 Comm: udevd 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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