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BUG: KCSAN: data-race in console_unlock / console_unlock

write to 0xffffffff8454e940 of 8 bytes by task 15258 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
 set_capacity_and_notify+0x15a/0x1c0 block/genhd.c:73
 loop_set_size drivers/block/loop.c:255 [inline]
 loop_configure+0xafc/0xcb0 drivers/block/loop.c:1162
 lo_ioctl+0x555/0x11f0 drivers/block/loop.c:1690
 blkdev_ioctl+0x1d0/0x3c0 block/ioctl.c:585
 block_ioctl+0x6d/0x80 fs/block_dev.c:1662
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:1055
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff8454e940 of 8 bytes by task 15261 on cpu 0:
 console_unlock+0x9f5/0xb30 kernel/printk/printk.c:2667
 do_con_write+0x5d2c/0x5da0 drivers/tty/vt/vt.c:270
 con_write+0x20/0x40 drivers/tty/vt/vt.c:3255
 process_output_block drivers/tty/n_tty.c:592 [inline]
 n_tty_write+0x77b/0xaf0 drivers/tty/n_tty.c:2354
 do_tty_write drivers/tty/tty_io.c:1043 [inline]
 file_tty_write+0x409/0x660 drivers/tty/tty_io.c:1133
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1140
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_writev fs/read_write.c:939 [inline]
 do_writev+0x1e0/0x400 fs/read_write.c:982
 __do_sys_writev fs/read_write.c:1055 [inline]
 __se_sys_writev fs/read_write.c:1052 [inline]
 __x64_sys_writev+0x41/0x50 fs/read_write.c:1052
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x000000000000a56a -> 0x000000000000a56b

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15261 Comm: syz-executor.5 Tainted: G        W         5.13.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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