==================================================================
BUG: KCSAN: data-race in console_unlock / console_unlock

write to 0xffffffff8417c940 of 8 bytes by task 9777 on cpu 1:
 console_unlock+0x570/0xb30 kernel/printk/printk.c:2632
 vprintk_emit+0x125/0x3d0 kernel/printk/printk.c:2174
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2185
 vprintk+0x15a/0x170 kernel/printk/printk_safe.c:392
 printk+0x62/0x87 kernel/printk/printk.c:2216
 show_ip arch/x86/kernel/dumpstack.c:148 [inline]
 show_iret_regs+0x24/0x60 arch/x86/kernel/dumpstack.c:155
 __show_regs+0x1e/0x330 arch/x86/kernel/process_64.c:74
 show_regs_if_on_stack arch/x86/kernel/dumpstack.c:173 [inline]
 show_trace_log_lvl+0x548/0x600 arch/x86/kernel/dumpstack.c:298
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xb7/0x103 lib/dump_stack.c:105
 dump_stack+0x11/0x1a lib/dump_stack.c:112
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail+0x23c/0x250 lib/fault-inject.c:146
 should_fail_usercopy+0x16/0x20 lib/fault-inject-usercopy.c:37
 copyin lib/iov_iter.c:164 [inline]
 _copy_from_iter+0x131/0x970 lib/iov_iter.c:718
 copy_from_iter include/linux/uio.h:148 [inline]
 do_tty_write drivers/tty/tty_io.c:1035 [inline]
 file_tty_write+0x3d1/0x660 drivers/tty/tty_io.c:1110
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1131
 call_write_iter include/linux/fs.h:2114 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x69d/0x770 fs/read_write.c:605
 ksys_write+0xce/0x180 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:667
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff8417c940 of 8 bytes by task 9776 on cpu 0:
 console_unlock+0x9f5/0xb30 kernel/printk/printk.c:2667
 con_shutdown+0x47/0x50 drivers/tty/vt/vt.c:3393
 release_tty+0x80/0x500 drivers/tty/tty_io.c:1605
 tty_release_struct+0x93/0xb0 drivers/tty/tty_io.c:1717
 tty_release+0x993/0xa10 drivers/tty/tty_io.c:1878
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x477/0x1530 kernel/exit.c:825
 do_group_exit+0xce/0x1a0 kernel/exit.c:922
 get_signal+0xfa3/0x15e0 kernel/signal.c:2808
 arch_do_signal_or_restart+0x2a/0x220 arch/x86/kernel/signal.c:865
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x109/0x190 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x49/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000000000005eb -> 0x00000000000005ec

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9776 Comm: syz-executor.1 Not tainted 5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================