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BUG: KCSAN: data-race in __mutex_lock / __mutex_lock

write to 0xffff888124366070 of 8 bytes by task 10862 on cpu 1:
 __mutex_remove_waiter kernel/locking/mutex.c:249 [inline]
 __mutex_lock_common kernel/locking/mutex.c:786 [inline]
 __mutex_lock+0x9d2/0xf40 kernel/locking/mutex.c:821
 __mutex_lock_interruptible_slowpath+0xa/0x10 kernel/locking/mutex.c:1179
 mutex_lock_interruptible+0x8c/0xa0 kernel/locking/mutex.c:1112
 tty_write_lock drivers/tty/tty_io.c:942 [inline]
 iterate_tty_write drivers/tty/tty_io.c:958 [inline]
 file_tty_write+0x2b5/0x690 drivers/tty/tty_io.c:1081
 tty_write+0x25/0x30 drivers/tty/tty_io.c:1102
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57d/0x990 fs/read_write.c:687
 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+0x27e1/0x3020 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888124366070 of 8 bytes by task 10859 on cpu 0:
 __mutex_lock_common kernel/locking/mutex.c:728 [inline]
 __mutex_lock+0x52d/0xf40 kernel/locking/mutex.c:821
 __mutex_lock_interruptible_slowpath+0xa/0x10 kernel/locking/mutex.c:1179
 mutex_lock_interruptible+0x8c/0xa0 kernel/locking/mutex.c:1112
 tty_write_lock drivers/tty/tty_io.c:942 [inline]
 iterate_tty_write drivers/tty/tty_io.c:958 [inline]
 file_tty_write+0x2b5/0x690 drivers/tty/tty_io.c:1081
 tty_write+0x25/0x30 drivers/tty/tty_io.c:1102
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x57d/0x990 fs/read_write.c:687
 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+0x27e1/0x3020 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffffc90010913ca8 -> 0xffffc9001097fca8

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10859 Comm: syz.0.2761 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
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