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BUG: KCSAN: data-race in console_lock / printk_kthread_func

write to 0xffffffff85c348a0 of 1 bytes by task 24748 on cpu 0:
 console_kthreads_block kernel/printk/printk.c:318 [inline]
 console_lock+0x65/0xd0 kernel/printk/printk.c:2713
 do_con_write+0x71/0x3590 drivers/tty/vt/vt.c:2908
 con_write+0x25/0x420 drivers/tty/vt/vt.c:3295
 process_output_block drivers/tty/n_tty.c:581 [inline]
 n_tty_write+0x7ea/0xb40 drivers/tty/n_tty.c:2248
 do_tty_write drivers/tty/tty_io.c:1024 [inline]
 file_tty_write+0x3f9/0x650 drivers/tty/tty_io.c:1095
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1116
 do_iter_readv_writev+0x27b/0x300
 do_iter_write+0x16f/0x5c0 fs/read_write.c:852
 vfs_iter_write+0x4c/0x70 fs/read_write.c:893
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x660 fs/splice.c:891
 do_splice_direct+0xfb/0x180 fs/splice.c:979
 do_sendfile+0x3ad/0x900 fs/read_write.c:1246
 __do_sys_sendfile64 fs/read_write.c:1311 [inline]
 __se_sys_sendfile64 fs/read_write.c:1297 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1297
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

read to 0xffffffff85c348a0 of 1 bytes by task 1396 on cpu 1:
 printer_should_wake kernel/printk/printk.c:3731 [inline]
 printk_kthread_func+0x481/0xb60 kernel/printk/printk.c:3795
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1396 Comm: pr/netcon0 Tainted: G        W         5.18.0-syzkaller-11080-g664a393a2663-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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