syzbot

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BUG: KCSAN: data-race in perf_event_set_state / perf_event_update_time

write to 0xffff888118f02878 of 8 bytes by task 13512 on cpu 0:
 perf_event_update_time+0x196/0x1d0 kernel/events/core.c:736
 perf_mmap+0xa4e/0xc60 kernel/events/core.c:7129
 vfs_mmap include/linux/fs.h:2290 [inline]
 mmap_file mm/internal.h:167 [inline]
 __mmap_new_file_vma mm/vma.c:2413 [inline]
 __mmap_new_vma mm/vma.c:2476 [inline]
 __mmap_region mm/vma.c:2669 [inline]
 mmap_region+0xfad/0x1630 mm/vma.c:2739
 do_mmap+0x9b3/0xbe0 mm/mmap.c:558
 vm_mmap_pgoff+0x17a/0x2e0 mm/util.c:580
 ksys_mmap_pgoff+0x268/0x310 mm/mmap.c:604
 x64_sys_call+0x14a3/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:10
 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 0xffff888118f02878 of 8 bytes by task 13511 on cpu 1:
 __perf_update_times kernel/events/core.c:719 [inline]
 perf_event_update_time kernel/events/core.c:734 [inline]
 perf_event_set_state+0x153/0x440 kernel/events/core.c:753
 event_sched_out+0x2d4/0x4d0 kernel/events/core.c:2393
 group_sched_out kernel/events/core.c:2417 [inline]
 __pmu_ctx_sched_out+0x263/0x530 kernel/events/core.c:3453
 ctx_sched_out+0x273/0x2d0 kernel/events/core.c:3541
 task_ctx_sched_out+0x4d/0x70 kernel/events/core.c:2861
 perf_event_context_sched_out kernel/events/core.c:3748 [inline]
 __perf_event_task_sched_out+0x286/0x370 kernel/events/core.c:3848
 perf_event_task_sched_out include/linux/perf_event.h:1654 [inline]
 prepare_task_switch kernel/sched/core.c:5155 [inline]
 context_switch kernel/sched/core.c:5304 [inline]
 __schedule+0xaf8/0xb30 kernel/sched/core.c:6961
 __schedule_loop kernel/sched/core.c:7043 [inline]
 schedule+0x5f/0xd0 kernel/sched/core.c:7058
 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:7115
 rwsem_down_write_slowpath+0x410/0x910 kernel/locking/rwsem.c:1185
 __down_write_common kernel/locking/rwsem.c:1317 [inline]
 __down_write_killable kernel/locking/rwsem.c:1331 [inline]
 down_write_killable+0x4d/0x80 kernel/locking/rwsem.c:1603
 mmap_write_lock_killable include/linux/mmap_lock.h:415 [inline]
 vm_mmap_pgoff+0xe3/0x2e0 mm/util.c:578
 ksys_mmap_pgoff+0x268/0x310 mm/mmap.c:604
 x64_sys_call+0x14a3/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:10
 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: 0x00000000000f72b7 -> 0x000000000011fc90

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 13511 Comm: syz.9.3381 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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