syzbot

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BUG: KCSAN: data-race in __bio_queue_enter / blk_mq_unfreeze_queue

read-write to 0xffff888101244a9c of 4 bytes by task 12116 on cpu 0:
 __blk_mq_unfreeze_queue block/blk-mq.c:184 [inline]
 blk_mq_unfreeze_queue+0x38/0xc0 block/blk-mq.c:195
 loop_set_status+0x414/0x550 drivers/block/loop.c:1293
 lo_ioctl+0x7fd/0x11d0
 blkdev_ioctl+0x35f/0x450 block/ioctl.c:676
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xd3/0x150 fs/ioctl.c:893
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893
 x64_sys_call+0x15cc/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888101244a9c of 4 bytes by task 12118 on cpu 1:
 __bio_queue_enter+0x164/0x500 block/blk-core.c:347
 bio_queue_enter block/blk.h:74 [inline]
 blk_mq_submit_bio+0x197/0xe30 block/blk-mq.c:2971
 __submit_bio+0xf2/0x470 block/blk-core.c:615
 __submit_bio_noacct_mq block/blk-core.c:696 [inline]
 submit_bio_noacct_nocheck+0x295/0x6e0 block/blk-core.c:725
 submit_bio_noacct+0x767/0x9b0 block/blk-core.c:853
 submit_bio+0x218/0x230 block/blk-core.c:895
 submit_bh_wbc+0x2de/0x320 fs/buffer.c:2824
 submit_bh+0x1e/0x30 fs/buffer.c:2829
 __ext4_read_bh fs/ext4/super.c:175 [inline]
 ext4_read_bh_nowait fs/ext4/super.c:187 [inline]
 ext4_read_bh_lock+0x16c/0x190 fs/ext4/super.c:211
 ext4_bread_batch+0x18d/0x360 fs/ext4/inode.c:950
 __ext4_find_entry+0x9d3/0x10a0 fs/ext4/namei.c:1627
 ext4_lookup_entry fs/ext4/namei.c:1727 [inline]
 ext4_lookup+0xba/0x390 fs/ext4/namei.c:1795
 lookup_open fs/namei.c:3556 [inline]
 open_last_lookups fs/namei.c:3647 [inline]
 path_openat+0xc5f/0x1f10 fs/namei.c:3883
 do_filp_open+0xf7/0x200 fs/namei.c:3913
 do_sys_openat2+0xab/0x120 fs/open.c:1416
 do_sys_open fs/open.c:1431 [inline]
 __do_sys_openat fs/open.c:1447 [inline]
 __se_sys_openat fs/open.c:1442 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1442
 x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 12118 Comm: syz.2.2264 Not tainted 6.11.0-rc3-syzkaller-00156-gd7a5aa4b3c00 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
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