==================================================================
BUG: KCSAN: data-race in _prb_read_valid / prb_reserve

write to 0xffffffff868e7ad0 of 88 bytes by task 26403 on cpu 0:
 prb_reserve+0x695/0xaf0 kernel/printk/printk_ringbuffer.c:1651
 vprintk_store+0x56d/0x860 kernel/printk/printk.c:2299
 vprintk_emit+0x10d/0x580 kernel/printk/printk.c:2399
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2438
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2448
 isofs_find_entry fs/isofs/namei.c:102 [inline]
 isofs_lookup+0x8b8/0x930 fs/isofs/namei.c:165
 __lookup_slow+0x193/0x250 fs/namei.c:1816
 lookup_slow+0x3c/0x60 fs/namei.c:1833
 walk_component+0x1ec/0x220 fs/namei.c:2151
 lookup_last fs/namei.c:2652 [inline]
 path_lookupat+0xfe/0x2a0 fs/namei.c:2676
 filename_lookup+0x147/0x340 fs/namei.c:2705
 kern_path+0x3b/0x130 fs/namei.c:2863
 create_local_trace_uprobe+0x53/0x2c0 kernel/trace/trace_uprobe.c:1650
 perf_uprobe_init+0xc0/0x150 kernel/trace/trace_event_perf.c:319
 perf_uprobe_event_init+0xc4/0x140 kernel/events/core.c:11170
 perf_try_init_event+0xd9/0x540 kernel/events/core.c:12605
 perf_init_event kernel/events/core.c:12703 [inline]
 perf_event_alloc+0xb27/0x1740 kernel/events/core.c:12978
 __do_sys_perf_event_open kernel/events/core.c:13496 [inline]
 __se_sys_perf_event_open+0x4a5/0x11c0 kernel/events/core.c:13377
 __x64_sys_perf_event_open+0x67/0x80 kernel/events/core.c:13377
 x64_sys_call+0x7bd/0x3000 arch/x86/include/generated/asm/syscalls_64.h:299
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff868e7ad0 of 8 bytes by task 2993 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:483 [inline]
 prb_first_seq kernel/printk/printk_ringbuffer.c:1975 [inline]
 _prb_read_valid+0x383/0x920 kernel/printk/printk_ringbuffer.c:2132
 prb_read_valid+0x3c/0x60 kernel/printk/printk_ringbuffer.c:2203
 syslog_print+0x146/0x540 kernel/printk/printk.c:1606
 do_syslog+0x52b/0x7e0 kernel/printk/printk.c:1758
 __do_sys_syslog kernel/printk/printk.c:1850 [inline]
 __se_sys_syslog kernel/printk/printk.c:1848 [inline]
 __x64_sys_syslog+0x41/0x50 kernel/printk/printk.c:1848
 x64_sys_call+0x2f45/0x3000 arch/x86/include/generated/asm/syscalls_64.h:104
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000002e74 -> 0x0000000000004e74

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 2993 Comm: klogd Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
==================================================================