Re: [syzbot] [xfs?] INFO: task hung in clean_bdev_aliases

From: Darrick J. Wong
Date: Wed Sep 06 2023 - 14:04:08 EST

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In reply to: Aleksandr Nogikh: "Re: [syzbot] [xfs?] INFO: task hung in clean_bdev_aliases"
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On Wed, Sep 06, 2023 at 07:20:15PM +0200, Aleksandr Nogikh wrote:
> On Tue, Sep 5, 2023 at 11:14 PM 'Dave Chinner' via syzkaller-bugs
> <syzkaller-bugs@xxxxxxxxxxxxxxxx> wrote:
> >
> > [cc linux-block, Christoph]
> >
> > Another iomap-blockdev related issue.
> >
> > #syz set subsystems: block
> >
> > syzbot developers: Please review how you are classifying subsystems,
> > this is the third false XFS classification in 24 hours.
>
> The reason why syzbot marked this report as xfs is that, per
> MAINTAINERS, fs/iomap/ points to linux-xfs@xxxxxxxxxxxxxxx. I can
> adjust the rules syzbot uses so that these are routed to "block".

Huh?

MAINTAINERS tells us that fs/iomap/ maps to "IOMAP FILESYSTEM LIBRARY",
why wouldn't it tag bugs with those stacktraces as "[iomap]" ?

They're separate subsystems that just happen to share the same vger
list because iomap was lifted from xfs.

> But should MAINTAINERS actually also not relate IOMAP FILESYSTEM
> LIBRARY with xfs in this case?

Did y'all try emailing those lists to ask how they'd like the function
name -> source file -> syzbot tagging set up?

--D

> --
> Aleksandr
>
> >
> > -Dave.
> >
> > On Mon, Sep 04, 2023 at 10:04:47PM -0700, syzbot wrote:
> > > Hello,
> > >
> > > syzbot found the following issue on:
> > >
> > > HEAD commit: 92901222f83d Merge tag 'f2fs-for-6-6-rc1' of git://git.ker..
> > > git tree: upstream
> > > console+strace: https://syzkaller.appspot.com/x/log.txt?x=1485e78fa80000
> > > kernel config: https://syzkaller.appspot.com/x/.config?x=3bd57a1ac08277b0
> > > dashboard link: https://syzkaller.appspot.com/bug?extid=1fa947e7f09e136925b8
> > > compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13fcf738680000
> > >
> > > Downloadable assets:
> > > disk image: https://storage.googleapis.com/syzbot-assets/ee486d884228/disk-92901222.raw.xz
> > > vmlinux: https://storage.googleapis.com/syzbot-assets/b5187db0b1d1/vmlinux-92901222.xz
> > > kernel image: https://storage.googleapis.com/syzbot-assets/82c4e42d693e/bzImage-92901222.xz
> > >
> > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > Reported-by: syzbot+1fa947e7f09e136925b8@xxxxxxxxxxxxxxxxxxxxxxxxx
> > >
> > > INFO: task syz-executor.5:10017 blocked for more than 143 seconds.
> > > Not tainted 6.5.0-syzkaller-11075-g92901222f83d #0
> > > "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> > > task:syz-executor.5 state:D stack:27624 pid:10017 ppid:5071 flags:0x00004006
> > > Call Trace:
> > > <TASK>
> > > context_switch kernel/sched/core.c:5382 [inline]
> > > __schedule+0xee1/0x59f0 kernel/sched/core.c:6695
> > > schedule+0xe7/0x1b0 kernel/sched/core.c:6771
> > > io_schedule+0xbe/0x130 kernel/sched/core.c:9026
> > > folio_wait_bit_common+0x3d2/0x9b0 mm/filemap.c:1304
> > > folio_lock include/linux/pagemap.h:1042 [inline]
> > > clean_bdev_aliases+0x56b/0x610 fs/buffer.c:1725
> > > clean_bdev_bh_alias include/linux/buffer_head.h:219 [inline]
> > > __block_write_begin_int+0x8d6/0x1470 fs/buffer.c:2115
> > > iomap_write_begin+0x5be/0x17b0 fs/iomap/buffered-io.c:772
> > > iomap_write_iter fs/iomap/buffered-io.c:907 [inline]
> > > iomap_file_buffered_write+0x3d6/0x9a0 fs/iomap/buffered-io.c:968
> > > blkdev_buffered_write block/fops.c:634 [inline]
> > > blkdev_write_iter+0x572/0xca0 block/fops.c:688
> > > call_write_iter include/linux/fs.h:1985 [inline]
> > > do_iter_readv_writev+0x21e/0x3c0 fs/read_write.c:735
> > > do_iter_write+0x17f/0x830 fs/read_write.c:860
> > > vfs_iter_write+0x7a/0xb0 fs/read_write.c:901
> > > iter_file_splice_write+0x698/0xbf0 fs/splice.c:736
> > > do_splice_from fs/splice.c:933 [inline]
> > > direct_splice_actor+0x118/0x180 fs/splice.c:1142
> > > splice_direct_to_actor+0x347/0xa30 fs/splice.c:1088
> > > do_splice_direct+0x1af/0x280 fs/splice.c:1194
> > > do_sendfile+0xb88/0x1390 fs/read_write.c:1254
> > > __do_sys_sendfile64 fs/read_write.c:1322 [inline]
> > > __se_sys_sendfile64 fs/read_write.c:1308 [inline]
> > > __x64_sys_sendfile64+0x1d6/0x220 fs/read_write.c:1308
> > > do_syscall_x64 arch/x86/entry/common.c:50 [inline]
> > > do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
> > > entry_SYSCALL_64_after_hwframe+0x63/0xcd
> > > RIP: 0033:0x7fdb8ca7cae9
> > > RSP: 002b:00007ffcd642da18 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
> > > RAX: ffffffffffffffda RBX: 00007fdb8cb9bf80 RCX: 00007fdb8ca7cae9
> > > RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003
> > > RBP: 00007fdb8cac847a R08: 0000000000000000 R09: 0000000000000000
> > > R10: 0100000000000042 R11: 0000000000000246 R12: 0000000000000000
> > > R13: 0000000000000be7 R14: 00007fdb8cb9bf80 R15: 00007fdb8cb9bf80
> > > </TASK>
> > > INFO: lockdep is turned off.
> > > NMI backtrace for cpu 1
> > > CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.5.0-syzkaller-11075-g92901222f83d #0
> > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
> > > Call Trace:
> > > <TASK>
> > > __dump_stack lib/dump_stack.c:88 [inline]
> > > dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
> > > nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113
> > > nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62
> > > trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
> > > check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
> > > watchdog+0xfac/0x1230 kernel/hung_task.c:379
> > > kthread+0x33a/0x430 kernel/kthread.c:388
> > > ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
> > > ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
> > > </TASK>
> > > Sending NMI from CPU 1 to CPUs 0:
> > > NMI backtrace for cpu 0
> > > CPU: 0 PID: 17 Comm: rcu_preempt Not tainted 6.5.0-syzkaller-11075-g92901222f83d #0
> > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
> > > RIP: 0010:load_balance+0x10a/0x3130 kernel/sched/fair.c:10983
> > > Code: 4a 8d 3c f5 40 aa 5c 8c 48 ba 00 00 00 00 00 fc ff df 48 89 f9 48 c1 e9 03 80 3c 11 00 0f 85 2f 2e 00 00 31 c0 b9 0c 00 00 00 <4e> 8b 1c f5 40 aa 5c 8c 4c 89 94 24 f8 00 00 00 48 8d bc 24 00 01
> > > RSP: 0018:ffffc900001676c8 EFLAGS: 00000046
> > > RAX: 0000000000000000 RBX: ffff8880b983c700 RCX: 000000000000000c
> > > RDX: dffffc0000000000 RSI: ffffffff8ae90360 RDI: ffffffff8c5caa40
> > > RBP: ffffc90000167898 R08: ffffc90000167960 R09: 0000000000000000
> > > R10: ffff88801525ac00 R11: 0000000000000000 R12: 00000000000287d8
> > > R13: ffffc90000167960 R14: 0000000000000000 R15: 0000000100004d48
> > > FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
> > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > > CR2: 0000000020000240 CR3: 000000000c976000 CR4: 0000000000350ef0
> > > Call Trace:
> > > <NMI>
> > > </NMI>
> > > <TASK>
> > > newidle_balance+0x710/0x1210 kernel/sched/fair.c:12059
> > > pick_next_task_fair+0x87/0x1200 kernel/sched/fair.c:8234
> > > __pick_next_task kernel/sched/core.c:6004 [inline]
> > > pick_next_task kernel/sched/core.c:6079 [inline]
> > > __schedule+0x493/0x59f0 kernel/sched/core.c:6659
> > > schedule+0xe7/0x1b0 kernel/sched/core.c:6771
> > > schedule_timeout+0x157/0x2c0 kernel/time/timer.c:2167
> > > rcu_gp_fqs_loop+0x1ec/0xa50 kernel/rcu/tree.c:1613
> > > rcu_gp_kthread+0x249/0x380 kernel/rcu/tree.c:1812
> > > kthread+0x33a/0x430 kernel/kthread.c:388
> > > ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
> > > ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
> > > </TASK>
> > >
> > >
> > > ---
> > > This report is generated by a bot. It may contain errors.
> > > See https://goo.gl/tpsmEJ for more information about syzbot.
> > > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.
> > >
> > > syzbot will keep track of this issue. See:
> > > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
> > >
> > > If the bug is already fixed, let syzbot know by replying with:
> > > #syz fix: exact-commit-title
> > >
> > > If you want syzbot to run the reproducer, reply with:
> > > #syz test: git://repo/address.git branch-or-commit-hash
> > > If you attach or paste a git patch, syzbot will apply it before testing.
> > >
> > > If you want to overwrite bug's subsystems, reply with:
> > > #syz set subsystems: new-subsystem
> > > (See the list of subsystem names on the web dashboard)
> > >
> > > If the bug is a duplicate of another bug, reply with:
> > > #syz dup: exact-subject-of-another-report
> > >
> > > If you want to undo deduplication, reply with:
> > > #syz undup
> > >
> >
> > --
> > Dave Chinner
> > david@xxxxxxxxxxxxx
> >

Next message: Kees Cook: "Re: [PATCH] x86/vmlinux: Fix linker fill bytes for ld.lld"
Previous message: Paul E. McKenney: "Re: [PATCH v2 1/2] maple_tree: Disable mas_wr_append() when other readers are possible"
In reply to: Aleksandr Nogikh: "Re: [syzbot] [xfs?] INFO: task hung in clean_bdev_aliases"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]