INFO: task can't die in __blk_mq_delay_run_hw_queue

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 92d00774360d Add linux-next specific files for 20210810
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=160ea779300000
kernel config: https://syzkaller.appspot.com/x/.config?x=a6933fa6f9a86ca9
dashboard link: https://syzkaller.appspot.com/bug?extid=3f8a87508cd62a717029
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1
CC: [ax...@kernel.dk linux...@vger.kernel.org linux-...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+3f8a87...@syzkaller.appspotmail.com

INFO: task syz-executor.0:23508 can't die for more than 143 seconds.
task:syz-executor.0 state:R running task stack:24584 pid:23508 ppid: 22131 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:4698 [inline]
__schedule+0x93a/0x26f0 kernel/sched/core.c:5955
preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6115
preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
__blk_mq_delay_run_hw_queue+0x573/0x640 block/blk-mq.c:1578
blk_mq_run_hw_queue+0x16c/0x2f0 block/blk-mq.c:1630
blk_mq_sched_insert_requests+0x1d5/0x680 block/blk-mq-sched.c:513
blk_mq_flush_plug_list+0x3d8/0x560 block/blk-mq.c:1955
blk_flush_plug_list block/blk-core.c:1719 [inline]
blk_finish_plug block/blk-core.c:1736 [inline]
blk_finish_plug+0x83/0xe0 block/blk-core.c:1732
read_pages+0x737/0xfa0 mm/readahead.c:150
page_cache_ra_unbounded+0x4c2/0x940 mm/readahead.c:225
do_page_cache_ra+0xf9/0x140 mm/readahead.c:269
do_sync_mmap_readahead mm/filemap.c:2988 [inline]
filemap_fault+0x1553/0x2780 mm/filemap.c:3081
__do_fault+0x10d/0x4f0 mm/memory.c:3858
do_read_fault mm/memory.c:4173 [inline]
do_fault mm/memory.c:4302 [inline]
handle_pte_fault mm/memory.c:4560 [inline]
__handle_mm_fault+0x28ea/0x5150 mm/memory.c:4695
handle_mm_fault+0x1c8/0x790 mm/memory.c:4793
faultin_page mm/gup.c:949 [inline]
__get_user_pages+0x503/0xf70 mm/gup.c:1170
populate_vma_page_range+0x24d/0x330 mm/gup.c:1502
__mm_populate+0x1ea/0x3e0 mm/gup.c:1611
mm_populate include/linux/mm.h:2719 [inline]
vm_mmap_pgoff+0x20e/0x290 mm/util.c:549
ksys_mmap_pgoff+0x4a8/0x620 mm/mmap.c:1636
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665e9
RSP: 002b:00007f13ce41f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9
RDX: 0000000001000002 RSI: 0000000000b36000 RDI: 0000000020000000
RBP: 00000000004bfcc4 R08: 0000000000000004 R09: 0000000000000000
R10: 0000000000028011 R11: 0000000000000246 R12: 000000000056c038
R13: 00007ffd3eb47d5f R14: 00007f13ce41f300 R15: 0000000000022000
INFO: task syz-executor.0:23512 can't die for more than 143 seconds.
task:syz-executor.0 state:R running task stack:24624 pid:23512 ppid: 22131 flags:0x0000400e
Call Trace:
context_switch kernel/sched/core.c:4698 [inline]
__schedule+0x93a/0x26f0 kernel/sched/core.c:5955
INFO: lockdep is turned off.


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.