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BUG: KCSAN: data-race in console_unlock / console_unlock

write to 0xffffffff8417d940 of 8 bytes by task 15676 on cpu 0:
 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:66
 loop_set_size drivers/block/loop.c:298 [inline]
 loop_configure+0xc8e/0xeb0 drivers/block/loop.c:1295
 lo_ioctl+0x59b/0x1340 drivers/block/loop.c:1847
 blkdev_ioctl+0x1d0/0x3c0 block/ioctl.c:585
 block_ioctl+0x6d/0x80 fs/block_dev.c:1604
 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_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 15677 on cpu 1:
 console_unlock+0x9f5/0xb30 kernel/printk/printk.c:2667
 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_read_bpb fs/fat/inode.c:1490 [inline]
 fat_fill_super+0x1713/0x2a80 fs/fat/inode.c:1656
 vfat_fill_super+0x2c/0x40 fs/fat/namei_vfat.c:1051
 mount_bdev+0x1e8/0x290 fs/super.c:1368
 vfat_mount+0x2d/0x40 fs/fat/namei_vfat.c:1058
 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:2919 [inline]
 path_mount+0x11d4/0x1ce0 fs/namespace.c:3249
 do_mount fs/namespace.c:3262 [inline]
 __do_sys_mount fs/namespace.c:3470 [inline]
 __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3447
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3447
 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: 0x000000000000111f -> 0x0000000000001120

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 15677 Comm: syz-executor.2 Not tainted 5.14.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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