udevd[4968]: inotify_add_watch(7, /dev/loop5p4, 10) failed: No such file or directory
==================================================================
BUG: KCSAN: data-race in data_push_tail / string

write to 0xffffffff88e4a538 of 1 bytes by task 6975 on cpu 1:
 string_nocheck lib/vsprintf.c:643 [inline]
 string+0x187/0x220 lib/vsprintf.c:721
 vsnprintf+0x532/0x890 lib/vsprintf.c:2852
 vscnprintf+0x41/0x90 lib/vsprintf.c:2917
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216
 vprintk_store+0x599/0x860 kernel/printk/printk.c:2336
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 devkmsg_emit+0x7f/0xb0 kernel/printk/printk.c:755
 devkmsg_write+0x1e3/0x2b0 kernel/printk/printk.c:818
 do_iter_readv_writev+0x41e/0x4c0 fs/read_write.c:-1
 vfs_writev+0x2c9/0x870 fs/read_write.c:1055
 do_writev+0xe7/0x210 fs/read_write.c:1101
 __do_sys_writev fs/read_write.c:1169 [inline]
 __se_sys_writev fs/read_write.c:1166 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1166
 x64_sys_call+0x2006/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff88e4a538 of 8 bytes by task 4968 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0xfd/0x420 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbf/0x2b0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x808/0xaf0 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2326
 vprintk_emit+0x178/0x650 kernel/printk/printk.c:2426
 devkmsg_emit+0x7f/0xb0 kernel/printk/printk.c:755
 devkmsg_write+0x1e3/0x2b0 kernel/printk/printk.c:818
 do_iter_readv_writev+0x41e/0x4c0 fs/read_write.c:-1
 vfs_writev+0x2c9/0x870 fs/read_write.c:1055
 do_writev+0xe7/0x210 fs/read_write.c:1101
 __do_sys_writev fs/read_write.c:1169 [inline]
 __se_sys_writev fs/read_write.c:1166 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1166
 x64_sys_call+0x2006/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000ffffeca9 -> 0x00000a79726f7463

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4968 Comm: udevd Not tainted 6.15.0-rc4-syzkaller-00256-g95d3481af6dc #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
==================================================================
udevd[4968]: inotify_add_watch(7, /dev/loop4p4, 10) failed: No such file or directory
udevd[4968]: inotify_add_watch(7, /dev/loop4p4, 10) failed: No such file or directory