[moderation] [trace?] KCSAN: data-race in probe_sched_wakeup / tracing_stop_cmdline_record

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 388b607d107c Merge tag 'efi-next-for-v7.3' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12451179580000
kernel config: https://syzkaller.appspot.com/x/.config?x=3f26454114340ba2
dashboard link: https://syzkaller.appspot.com/bug?extid=6081b58df5a5a2bf38af
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
CC: [linux-...@vger.kernel.org linux-tra...@vger.kernel.org mathieu....@efficios.com mhir...@kernel.org ros...@goodmis.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/04f536871fd4/disk-388b607d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/79d441b37e9a/vmlinux-388b607d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/bca49ceeaa9c/bzImage-388b607d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6081b5...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in probe_sched_wakeup / tracing_stop_cmdline_record

read-write to 0xffffffff895ee1e0 of 4 bytes by task 5659 on cpu 0:
tracing_stop_sched_switch kernel/trace/trace_sched_switch.c:120 [inline]
tracing_stop_cmdline_record+0x28/0xc0 kernel/trace/trace_sched_switch.c:140
__ftrace_event_enable_disable+0x323/0x4b0 kernel/trace/trace_events.c:848
ftrace_event_enable_disable kernel/trace/trace_events.c:934 [inline]
ftrace_clear_events kernel/trace/trace_events.c:1057 [inline]
ftrace_event_set_open+0xe6/0x200 kernel/trace/trace_events.c:2892
do_dentry_open+0x49f/0xa60 fs/open.c:996
vfs_open+0x37/0x1e0 fs/open.c:1101
do_open fs/namei.c:4837 [inline]
path_openat+0xc01/0x10d0 fs/namei.c:5000
do_file_open+0x16c/0x290 fs/namei.c:5029
do_sys_openat2+0xa0/0x130 fs/open.c:1417
do_sys_open fs/open.c:1423 [inline]
__do_sys_openat fs/open.c:1439 [inline]
__se_sys_openat fs/open.c:1434 [inline]
__x64_sys_openat+0xf2/0x120 fs/open.c:1434
x64_sys_call+0x1f72/0x2550 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff895ee1e0 of 4 bytes by task 5658 on cpu 1:
probe_sched_wakeup+0x41/0xa0 kernel/trace/trace_sched_switch.c:45
__traceiter_sched_wakeup+0x26/0x40 include/trace/events/sched.h:178
__do_trace_sched_wakeup include/trace/events/sched.h:178 [inline]
trace_sched_wakeup include/trace/events/sched.h:178 [inline]
ttwu_do_wakeup kernel/sched/core.c:3740 [inline]
ttwu_do_activate+0x201/0x230 kernel/sched/core.c:3837
ttwu_queue kernel/sched/core.c:4087 [inline]
try_to_wake_up+0x43f/0x6a0 kernel/sched/core.c:4425
autoremove_wake_function+0x10/0x50 kernel/sched/wait.c:404
__wake_up_common kernel/sched/wait.c:109 [inline]
__wake_up_common_lock kernel/sched/wait.c:126 [inline]
__wake_up_sync_key+0x52/0x80 kernel/sched/wait.c:193
__unix_dgram_recvmsg+0x3a4/0x860 net/unix/af_unix.c:2615
unix_dgram_recvmsg+0x7e/0x90 net/unix/af_unix.c:2689
sock_recvmsg_nosec+0xc2/0xf0 net/socket.c:1151
____sys_recvmsg+0x26f/0x280 net/socket.c:2931
___sys_recvmsg+0x11f/0x3a0 net/socket.c:2975
do_recvmmsg+0x1e5/0x560 net/socket.c:3070
__sys_recvmmsg net/socket.c:3144 [inline]
__do_sys_recvmmsg net/socket.c:3167 [inline]
__se_sys_recvmmsg net/socket.c:3160 [inline]
__x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3160
x64_sys_call+0x77f/0x2550 arch/x86/include/generated/asm/syscalls_64.h:300
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x112/0x360 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000095a -> 0x00000959

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5658 Comm: syz.6.587 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
==================================================================


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