[syzbot] Monthly block report (Sep 2026)

Hello block maintainers/developers,

This is a 31-day syzbot report for the block subsystem.
All related reports/information can be found at:
https://syzkaller.appspot.com/upstream/s/block

During the period, 10 new issues were detected and 4 were fixed.
In total, 32 issues are still open and 118 have already been fixed.
There are also 30 low-priority issues.

Some of the still happening issues:

Ref  Crashes Repro Title
<1>  1741    Yes   INFO: task hung in blkdev_fallocate
                   https://syzkaller.appspot.com/bug?extid=39b75c02b8be0a061bfc
<2>  87      No    INFO: task hung in read_cache_folio (6)
                   https://syzkaller.appspot.com/bug?extid=9db0864859224b833108
<3>  57      Yes   INFO: task hung in __rq_qos_throttle (2)
                   https://syzkaller.appspot.com/bug?extid=53706c567afab5131044
<4>  29      No    possible deadlock in blkcg_deactivate_policy (2)
                   https://syzkaller.appspot.com/bug?extid=14254d81dd19ba7d7e41
<5>  16      Yes   INFO: task hung in blkdev_read_iter
                   https://syzkaller.appspot.com/bug?extid=afa7aef0c237038586e7
<6>  11      No    BUG: unable to handle kernel paging request in blk_mq_complete_request_remote
                   https://syzkaller.appspot.com/bug?extid=2e3bf0bd49acd9b21d4b
<7>  1249    Yes   WARNING in blk_mq_free_tag_set
                   https://syzkaller.appspot.com/bug?extid=02b37e31e64ea5cb6d29
<8>  94      Yes   INFO: rcu detected stall in kjournald2 (2)
                   https://syzkaller.appspot.com/bug?extid=14c6ac6811273526cfa5
<9>  30      Yes   KASAN: slab-out-of-bounds Read in blk_mq_free_rqs
                   https://syzkaller.appspot.com/bug?extid=e90526cab23b9efcd03c
<10> 13      No    KASAN: slab-out-of-bounds Read in seq_buf_putmem
                   https://syzkaller.appspot.com/bug?extid=f179b16e13624138b0f1

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