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BUG: KCSAN: data-race in console_unlock / console_unlock

write to 0xffffffff8417d940 of 8 bytes by task 15271 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
 fat_msg+0x80/0xaf fs/fat/misc.c:56
 fat__get_entry fs/fat/dir.c:102 [inline]
 fat_get_entry+0x540/0x5f0 fs/fat/dir.c:128
 fat_get_short_entry fs/fat/dir.c:873 [inline]
 fat_subdirs+0x10c/0x1b0 fs/fat/dir.c:939
 fat_read_root fs/fat/inode.c:1413 [inline]
 fat_fill_super+0x254c/0x2a80 fs/fat/inode.c:1863
 msdos_fill_super+0x29/0x30 fs/fat/namei_msdos.c:655
 mount_bdev+0x1e8/0x290 fs/super.c:1368
 msdos_mount+0x2d/0x40 fs/fat/namei_msdos.c:662
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:610
 vfs_get_tree+0x4a/0x1a0 fs/super.c:1498
 do_new_mount fs/namespace.c:2923 [inline]
 path_mount+0x11f2/0x1d30 fs/namespace.c:3253
 do_mount fs/namespace.c:3266 [inline]
 __do_sys_mount fs/namespace.c:3474 [inline]
 __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3451
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3451
 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 0xffffffff8417d940 of 8 bytes by task 15274 on cpu 0:
 console_unlock+0x9f5/0xb30 kernel/printk/printk.c:2667
 do_con_write+0x5d29/0x5d90 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:2288
 do_tty_write drivers/tty/tty_io.c:1038 [inline]
 file_tty_write+0x409/0x660 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

value changed: 0x00000000000070bb -> 0x00000000000070bc

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 15274 Comm: syz-executor.3 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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