syzbot

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BUG: KCSAN: data-race in blk_mq_unfreeze_queue / blk_queue_enter

write to 0xffff88812aa44814 of 4 bytes by task 30831 on cpu 0:
 blk_mq_unfreeze_queue+0x4c/0xc0 block/blk-mq.c:189
 loop_set_status+0x886/0xb30 drivers/block/loop.c:1344
 loop_set_status64+0x6d/0xb0 drivers/block/loop.c:1476
 lo_ioctl+0x30b/0xc80 drivers/block/loop.c:1619
 __blkdev_driver_ioctl block/ioctl.c:277 [inline]
 blkdev_ioctl+0xbe5/0x1260 block/ioctl.c:582
 block_ioctl+0x95/0xc0 fs/block_dev.c:1983
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x84f/0xcf0 fs/ioctl.c:732
 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:754
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812aa44814 of 4 bytes by task 30827 on cpu 1:
 blk_queue_enter+0x400/0x570 block/blk-core.c:440
 generic_make_request block/blk-core.c:1060 [inline]
 generic_make_request+0x121/0x700 block/blk-core.c:1008
 submit_bio+0x96/0x3c0 block/blk-core.c:1192
 submit_bh_wbc+0x40f/0x460 fs/buffer.c:3135
 submit_bh fs/buffer.c:3141 [inline]
 block_read_full_page+0x5c9/0x6d0 fs/buffer.c:2336
 blkdev_readpage+0x26/0x40 fs/block_dev.c:614
 generic_file_buffered_read mm/filemap.c:2188 [inline]
 generic_file_read_iter+0xbfa/0x1440 mm/filemap.c:2324
 blkdev_read_iter+0xb2/0xe0 fs/block_dev.c:2039
 call_read_iter include/linux/fs.h:1896 [inline]
 new_sync_read+0x389/0x4f0 fs/read_write.c:414
 __vfs_read+0xb1/0xc0 fs/read_write.c:427
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446
 ksys_read+0xd5/0x1b0 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x4c/0x60 fs/read_write.c:595
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 30827 Comm: blkid Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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