syzbot

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BUG: KCSAN: data-race in __bio_queue_enter / blk_mq_unfreeze_queue

read-write to 0xffff888101b1f31c of 4 bytes by task 1821 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_clr_fd+0x244/0x3c0 drivers/block/loop.c:1172
 loop_clr_fd drivers/block/loop.c:1257 [inline]
 lo_ioctl+0xd8c/0x1290 drivers/block/loop.c:1563
 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 0xffff888101b1f31c of 4 bytes by task 26008 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:2794 [inline]
 blk_mq_submit_bio+0x351/0xe90 block/blk-mq.c:2896
 __submit_bio block/blk-core.c:591 [inline]
 __submit_bio_noacct_mq block/blk-core.c:668 [inline]
 submit_bio_noacct_nocheck+0x83d/0xaa0 block/blk-core.c:685
 submit_bio_noacct+0x6a5/0x810 block/blk-core.c:791
 submit_bio+0xfb/0x110 block/blk-core.c:827
 mpage_bio_submit fs/mpage.c:64 [inline]
 mpage_readahead+0x280/0x2c0 fs/mpage.c:364
 blkdev_readahead+0x18/0x20 block/fops.c:386
 read_pages+0xa6/0x560 mm/readahead.c:161
 page_cache_ra_unbounded+0x2de/0x320 mm/readahead.c:270
 do_page_cache_ra mm/readahead.c:300 [inline]
 force_page_cache_ra+0x1c6/0x200 mm/readahead.c:331
 page_cache_sync_ra+0xc8/0xf0 mm/readahead.c:705
 page_cache_sync_readahead include/linux/pagemap.h:1213 [inline]
 filemap_get_pages mm/filemap.c:2581 [inline]
 filemap_read+0x3fd/0x1510 mm/filemap.c:2675
 blkdev_read_iter+0x2c6/0x370 block/fops.c:598
 call_read_iter include/linux/fs.h:2185 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3a5/0x560 fs/read_write.c:470
 ksys_read+0xe8/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:621
 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: 26008 Comm: udevd Not tainted 6.0.0-syzkaller-10822-g60bb8154d1d7-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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I/O error, dev loop3, sector 3968 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2
I/O error, dev loop1, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 2