syzbot

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BUG: KCSAN: data-race in __bio_queue_enter / blk_freeze_queue

read-write to 0xffff888100f682e4 of 4 bytes by task 7512 on cpu 1:
 blk_freeze_queue_start block/blk-mq.c:127 [inline]
 blk_freeze_queue+0x37/0xb0 block/blk-mq.c:166
 blk_mq_freeze_queue+0x15/0x20 block/blk-mq.c:176
 loop_set_status+0x135/0x550 drivers/block/loop.c:1285
 lo_ioctl+0x892/0x12e0
 blkdev_ioctl+0x375/0x460 block/ioctl.c:630
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888100f682e4 of 4 bytes by task 7394 on cpu 0:
 __bio_queue_enter+0x1e3/0x4f0 block/blk-core.c:358
 bio_queue_enter block/blk.h:70 [inline]
 blk_mq_get_new_requests block/blk-mq.c:2878 [inline]
 blk_mq_submit_bio+0x359/0xd70 block/blk-mq.c:2989
 __submit_bio+0x11c/0x350 block/blk-core.c:599
 __submit_bio_noacct_mq block/blk-core.c:678 [inline]
 submit_bio_noacct_nocheck+0x449/0x5e0 block/blk-core.c:707
 submit_bio_noacct+0x700/0x8a0 block/blk-core.c:801
 submit_bio+0xb7/0xc0 block/blk-core.c:834
 mpage_bio_submit_read fs/mpage.c:82 [inline]
 mpage_readahead+0x28a/0x2d0 fs/mpage.c:385
 blkdev_readahead+0x1c/0x20 block/fops.c:425
 read_pages+0x9f/0x530 mm/readahead.c:160
 page_cache_ra_unbounded+0x2aa/0x2e0 mm/readahead.c:269
 do_page_cache_ra mm/readahead.c:299 [inline]
 force_page_cache_ra mm/readahead.c:330 [inline]
 page_cache_sync_ra+0x24b/0x2a0 mm/readahead.c:691
 page_cache_sync_readahead include/linux/pagemap.h:1293 [inline]
 filemap_get_pages+0x251/0xe90 mm/filemap.c:2556
 filemap_read+0x214/0x680 mm/filemap.c:2652
 blkdev_read_iter+0x217/0x2c0 block/fops.c:730
 call_read_iter include/linux/fs.h:1950 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x3da/0x5c0 fs/read_write.c:470
 ksys_read+0xeb/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+0x42/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7394 Comm: udevd Tainted: G        W          6.6.0-rc3-syzkaller-00096-g71e58659bfc0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
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