From: syzbot <syzbot+8b41a1365f1106fd0f33@syzkaller.appspotmail.com>
To: asmadeus@codewreck.org, davem@davemloft.net, ericvh@gmail.com,
linux-kernel@vger.kernel.org, lucho@ionkov.net,
netdev@vger.kernel.org, syzkaller-bugs@googlegroups.com,
v9fs-developer@lists.sourceforge.net
Subject: Re: INFO: task hung in p9_fd_close
Date: Sat, 21 Sep 2019 09:19:06 -0700 [thread overview]
Message-ID: <000000000000c1d3ca0593128b24@google.com> (raw)
In-Reply-To: <00000000000039af4d05915a9f56@google.com>
syzbot has found a reproducer for the following crash on:
HEAD commit: f97c81dc Merge tag 'armsoc-late' of git://git.kernel.org/p..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=171a1555600000
kernel config: https://syzkaller.appspot.com/x/.config?x=61f948934213449f
dashboard link: https://syzkaller.appspot.com/bug?extid=8b41a1365f1106fd0f33
compiler: clang version 9.0.0 (/home/glider/llvm/clang
80fee25776c2fb61e74c1ecb1a523375c2500b69)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1641d429600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11eff9ad600000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+8b41a1365f1106fd0f33@syzkaller.appspotmail.com
INFO: task syz-executor635:8085 blocked for more than 143 seconds.
Not tainted 5.3.0+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor635 D27848 8085 8070 0x00004004
Call Trace:
context_switch kernel/sched/core.c:3384 [inline]
__schedule+0x82e/0xc50 kernel/sched/core.c:4056
schedule+0x131/0x1e0 kernel/sched/core.c:4123
schedule_timeout+0x46/0x240 kernel/time/timer.c:1869
do_wait_for_common+0x2e7/0x4d0 kernel/sched/completion.c:83
__wait_for_common kernel/sched/completion.c:104 [inline]
wait_for_common kernel/sched/completion.c:115 [inline]
wait_for_completion+0x47/0x60 kernel/sched/completion.c:136
__flush_work+0xd4/0x150 kernel/workqueue.c:3040
__cancel_work_timer+0x420/0x570 kernel/workqueue.c:3127
cancel_work_sync+0x17/0x20 kernel/workqueue.c:3163
p9_conn_destroy net/9p/trans_fd.c:868 [inline]
p9_fd_close+0x297/0x3c0 net/9p/trans_fd.c:898
p9_client_create+0x974/0xee0 net/9p/client.c:1068
v9fs_session_init+0x192/0x18e0 fs/9p/v9fs.c:406
v9fs_mount+0x82/0x860 fs/9p/vfs_super.c:124
legacy_get_tree+0xf9/0x1a0 fs/fs_context.c:659
vfs_get_tree+0x8f/0x380 fs/super.c:1542
do_new_mount fs/namespace.c:2825 [inline]
do_mount+0x16c7/0x2510 fs/namespace.c:3145
ksys_mount+0xcc/0x100 fs/namespace.c:3354
__do_sys_mount fs/namespace.c:3368 [inline]
__se_sys_mount fs/namespace.c:3365 [inline]
__x64_sys_mount+0xbf/0xd0 fs/namespace.c:3365
do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x447909
Code: e8 5c 14 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 9b 0c fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007eff1aea0db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00000000006ddc78 RCX: 0000000000447909
RDX: 00000000200005c0 RSI: 0000000020000540 RDI: 0000000000000000
RBP: 00000000006ddc70 R08: 0000000020000680 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc7c
R13: 00007ffc4e6377ef R14: 00007eff1aea19c0 R15: 000000000000002d
Showing all locks held in the system:
2 locks held by kworker/1:1/22:
#0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at: spin_unlock_irq
include/linux/spinlock.h:388 [inline]
#0: ffff8880aa4278e8 ((wq_completion)events){+.+.}, at:
process_one_work+0x75d/0x10e0 kernel/workqueue.c:2242
#1: ffff8880a9a3fd78 ((work_completion)(&m->wq)){+.+.}, at:
process_one_work+0x79f/0x10e0 kernel/workqueue.c:2244
1 lock held by khungtaskd/1053:
#0: ffffffff888d3900 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30
include/linux/rcupdate.h:207
1 lock held by rsyslogd/7959:
#0: ffff8880a99f1e20 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x243/0x2e0
fs/file.c:801
2 locks held by getty/8049:
#0: ffff8880a602d450 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8050:
#0: ffff8880a902ac50 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f092e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8051:
#0: ffff88809c0f1750 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f312e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8052:
#0: ffff88809e344b90 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f152e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8053:
#0: ffff88809e344310 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8054:
#0: ffff88809c8aa410 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f2d2e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
2 locks held by getty/8055:
#0: ffff8880a0267310 (&tty->ldisc_sem){++++}, at:
tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:272
#1: ffffc90005f012e0 (&ldata->atomic_read_lock){+.+.}, at:
n_tty_read+0x221/0x1b00 drivers/tty/n_tty.c:2156
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 1053 Comm: khungtaskd Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146
check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
watchdog+0xbb9/0xbd0 kernel/hung_task.c:289
kthread+0x332/0x350 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:check_preemption_disabled+0x6/0x2a0 lib/smp_processor_id.c:13
Code: 90 90 90 90 55 48 89 e5 e8 a7 b2 2e fe 48 c7 c7 79 91 38 88 48 c7 c6
10 72 4e 88 e8 04 00 00 00 5d c3 66 90 55 48 89 e5 41 57 <41> 56 41 55 41
54 53 48 83 ec 10 49 89 f6 49 89 ff e8 74 b2 2e fe
RSP: 0018:ffff8880aeb09ee0 EFLAGS: 00000093
RAX: ffffffff83448fc9 RBX: 0000000000000004 RCX: ffff8880a98c2340
RDX: 0000000000000000 RSI: ffffffff884e7210 RDI: ffffffff88389179
RBP: ffff8880aeb09ee8 R08: ffffffff816701e0 R09: fffffbfff117c3cd
R10: fffffbfff117c3cd R11: 0000000000000000 R12: 1ffff11015d64eaf
R13: ffff8880aeb00000 R14: dffffc0000000000 R15: ffff8880aeb2757c
FS: 0000000000000000(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000000a3d38000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
debug_smp_processor_id+0x1c/0x20 lib/smp_processor_id.c:57
tick_nohz_stop_idle kernel/time/tick-sched.c:535 [inline]
tick_nohz_irq_enter kernel/time/tick-sched.c:1255 [inline]
tick_irq_enter+0xbd/0x3e0 kernel/time/tick-sched.c:1274
irq_enter+0x52/0xc0 kernel/softirq.c:354
scheduler_ipi+0xb3/0x4a0 kernel/sched/core.c:2337
smp_reschedule_interrupt+0x7a/0xa0 arch/x86/kernel/smp.c:244
reschedule_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:854
</IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 3c fa eb ae 89 d9 80 e1 07 80 c1 03 38 c1 7c ba 48 89 df e8 94 ab 3c
fa eb b0 90 90 e9 07 00 00 00 0f 00 2d b6 99 52 00 fb f4 <c3> 90 e9 07 00
00 00 0f 00 2d a6 99 52 00 f4 c3 90 90 55 48 89 e5
RSP: 0018:ffff8880a98cfe10 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff02
RAX: 1ffffffff1115179 RBX: ffff8880a98c2340 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff812ba81a RDI: ffff8880a98c2b80
RBP: ffff8880a98cfe18 R08: ffff8880a98c2b98 R09: ffffed1015318469
R10: ffffed1015318469 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff11015318468 R14: dffffc0000000000 R15: 1ffffffff1115177
arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
default_idle_call+0x59/0xa0 kernel/sched/idle.c:94
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x140/0x670 kernel/sched/idle.c:264
cpu_startup_entry+0x25/0x30 kernel/sched/idle.c:356
start_secondary+0x384/0x410 arch/x86/kernel/smpboot.c:264
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241
next prev parent reply other threads:[~2019-09-21 16:19 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-30 19:28 INFO: task hung in p9_fd_close syzbot
2019-09-21 16:19 ` syzbot [this message]
2022-08-26 15:27 ` [PATCH] 9p/trans_fd: always use O_NONBLOCK read/write Tetsuo Handa
2022-08-27 6:11 ` [PATCH v2] 9p/trans_fd: perform read/write with TIF_SIGPENDING set Tetsuo Handa
2022-09-01 15:23 ` Christian Schoenebeck
2022-09-01 22:25 ` Tetsuo Handa
2022-09-03 23:39 ` Dominique Martinet
2022-09-04 0:27 ` Tetsuo Handa
2022-10-07 1:40 ` Dominique Martinet
2022-10-07 11:52 ` Tetsuo Handa
2022-10-06 14:55 ` [PATCH] 9p/trans_fd: always use O_NONBLOCK read/write Christian Schoenebeck
2022-10-07 1:03 ` Dominique Martinet
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=000000000000c1d3ca0593128b24@google.com \
--to=syzbot+8b41a1365f1106fd0f33@syzkaller.appspotmail.com \
--cc=asmadeus@codewreck.org \
--cc=davem@davemloft.net \
--cc=ericvh@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=lucho@ionkov.net \
--cc=netdev@vger.kernel.org \
--cc=syzkaller-bugs@googlegroups.com \
--cc=v9fs-developer@lists.sourceforge.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.