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BUG: KCSAN: data-race in probe_sched_switch / tracing_start_sched_switch

write to 0xffffffff89601220 of 4 bytes by task 10159 on cpu 1:
 tracing_start_sched_switch+0x8d/0x200 kernel/trace/trace_sched_switch.c:101
 tracing_start_cmdline_record+0x13/0x20 kernel/trace/trace_sched_switch.c:135
 __ftrace_event_enable_disable+0x203/0x4b0 kernel/trace/trace_events.c:894
 ftrace_event_enable_disable kernel/trace/trace_events.c:934 [inline]
 __ftrace_set_clr_event_nolock+0x39e/0x820 kernel/trace/trace_events.c:1404
 __ftrace_set_clr_event kernel/trace/trace_events.c:1437 [inline]
 ftrace_set_clr_event+0x2a6/0x340 kernel/trace/trace_events.c:1487
 ftrace_event_write+0x170/0x1d0 kernel/trace/trace_events.c:1577
 vfs_write+0x254/0x9a0 fs/read_write.c:685
 ksys_write+0xdc/0x1a0 fs/read_write.c:739
 __do_sys_write fs/read_write.c:750 [inline]
 __se_sys_write fs/read_write.c:747 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:747
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 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 0xffffffff89601220 of 4 bytes by task 10160 on cpu 0:
 probe_sched_switch+0x46/0xa0 kernel/trace/trace_sched_switch.c:32
 __traceiter_sched_switch+0x3f/0x60 include/trace/events/sched.h:220
 __do_trace_sched_switch include/trace/events/sched.h:220 [inline]
 trace_sched_switch include/trace/events/sched.h:220 [inline]
 __schedule+0xc34/0xd20 kernel/sched/core.c:7281
 __schedule_loop kernel/sched/core.c:7361 [inline]
 schedule+0x5b/0xa0 kernel/sched/core.c:7376
 schedule_timeout+0x53/0x180 kernel/time/sleep_timeout.c:75
 unix_wait_for_peer+0x135/0x1a0 net/unix/af_unix.c:1628
 unix_dgram_sendmsg+0x8c2/0x1030 net/unix/af_unix.c:2264
 sock_sendmsg_nosec net/socket.c:800 [inline]
 __sock_sendmsg net/socket.c:815 [inline]
 ____sys_sendmsg+0x532/0x580 net/socket.c:2713
 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2767
 __sys_sendmmsg+0x185/0x320 net/socket.c:2856
 __do_sys_sendmmsg net/socket.c:2883 [inline]
 __se_sys_sendmmsg net/socket.c:2880 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2880
 x64_sys_call+0x1fb4/0x2550 arch/x86/include/generated/asm/syscalls_64.h:308
 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: 0x00000285 -> 0x00000286

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10160 Comm: syz.3.1951 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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