syzbot

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BUG: KCSAN: data-race in __bio_queue_enter / blk_mq_unfreeze_queue

read-write to 0xffff88810247d734 of 4 bytes by task 20285 on cpu 0:
 __blk_mq_unfreeze_queue block/blk-mq.c:225 [inline]
 blk_mq_unfreeze_queue+0x34/0xb0 block/blk-mq.c:236
 loop_set_block_size drivers/block/loop.c:1501 [inline]
 lo_simple_ioctl drivers/block/loop.c:1522 [inline]
 lo_ioctl+0xbf5/0x1290 drivers/block/loop.c:1587
 blkdev_ioctl+0x20e/0x440 block/ioctl.c:614
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856
 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+0x63/0xcd

read to 0xffff88810247d734 of 4 bytes by task 20282 on cpu 1:
 __bio_queue_enter+0x1fa/0x510 block/blk-core.c:338
 bio_queue_enter block/blk.h:76 [inline]
 blk_mq_get_new_requests block/blk-mq.c:2800 [inline]
 blk_mq_submit_bio+0x351/0xe90 block/blk-mq.c:2902
 __submit_bio block/blk-core.c:590 [inline]
 __submit_bio_noacct_mq block/blk-core.c:667 [inline]
 submit_bio_noacct_nocheck+0x83d/0xaa0 block/blk-core.c:684
 submit_bio_noacct+0x6a5/0x810 block/blk-core.c:790
 submit_bio+0xfb/0x110 block/blk-core.c:826
 submit_bio_wait+0x7b/0xc0 block/bio.c:1320
 blkdev_issue_flush+0x4f/0x70 block/blk-flush.c:467
 blkdev_fsync+0x5b/0x80 block/fops.c:458
 vfs_fsync_range+0x107/0x120 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2891 [inline]
 blkdev_write_iter+0x36f/0x3e0 block/fops.c:543
 do_iter_write+0x494/0x750 fs/read_write.c:861
 vfs_iter_write+0x4c/0x70 fs/read_write.c:902
 iter_file_splice_write+0x44a/0x7c0 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:931
 splice_direct_to_actor+0x305/0x620 fs/splice.c:886
 do_splice_direct+0xfb/0x180 fs/splice.c:974
 do_sendfile+0x3bf/0x910 fs/read_write.c:1255
 __do_sys_sendfile64 fs/read_write.c:1323 [inline]
 __se_sys_sendfile64 fs/read_write.c:1309 [inline]
 __x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
 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+0x63/0xcd

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 20282 Comm: syz-executor.2 Not tainted 6.1.0-rc7-syzkaller-00200-gc2bf05db6c78-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
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