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INFO: task hung in __x64_sys_acct

Status: auto-closed as invalid on 2019/09/17 08:14
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+d2b787e0554154c403f5@syzkaller.appspotmail.com
First crash: 2031d, last: 1862d
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in __x64_sys_acct 1 1830d 1830d 0/1 auto-closed as invalid on 2019/10/19 23:41

Sample crash report:
INFO: task syz-executor.5:27166 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc1+ #31
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D29024 27166  15197 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 __do_sys_acct kernel/acct.c:285 [inline]
 __se_sys_acct kernel/acct.c:273 [inline]
 __x64_sys_acct+0xa6/0x200 kernel/acct.c:273
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458079
Code: Bad RIP value.
RSP: 002b:00007fbfff007c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458079
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fbfff0086d4
R13: 00000000004bdee5 R14: 00000000004ce370 R15: 00000000ffffffff
INFO: task syz-executor.1:27283 blocked for more than 143 seconds.
      Not tainted 5.1.0-rc1+ #31
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28368 27283  15934 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 __do_sys_acct kernel/acct.c:285 [inline]
 __se_sys_acct kernel/acct.c:273 [inline]
 __x64_sys_acct+0xa6/0x200 kernel/acct.c:273
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458079
Code: Bad RIP value.
RSP: 002b:00007f9f88efbc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a3
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000458079
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9f88efc6d4
R13: 00000000004bdee5 R14: 00000000004ce370 R15: 00000000ffffffff

Showing all locks held in the system:
1 lock held by khungtaskd/1042:
 #0: 00000000c246cf1a (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5061
2 locks held by udevd/3875:
1 lock held by rsyslogd/8080:
 #0: 00000000d81ce0f4 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801
2 locks held by getty/8224:
 #0: 0000000021aeb9b6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000e8fd0b3a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/8225:
 #0: 00000000d47ad70a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000001dcd0334 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/8226:
 #0: 000000005e3f4861 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 0000000026505f2a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/8227:
 #0: 000000003487e77e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000683c1335 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/8228:
 #0: 0000000020191643 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000fe58a202 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/8229:
 #0: 0000000049023ec7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000b9b3fe9c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/8230:
 #0: 00000000764cd916 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000007b9af41e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.5/27166:
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __do_sys_acct kernel/acct.c:285 [inline]
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __se_sys_acct kernel/acct.c:273 [inline]
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __x64_sys_acct+0xa6/0x200 kernel/acct.c:273
1 lock held by syz-executor.1/27171:
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __do_sys_acct kernel/acct.c:285 [inline]
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __se_sys_acct kernel/acct.c:273 [inline]
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __x64_sys_acct+0xa6/0x200 kernel/acct.c:273
1 lock held by syz-executor.1/27283:
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __do_sys_acct kernel/acct.c:285 [inline]
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __se_sys_acct kernel/acct.c:273 [inline]
 #0: 00000000feb1e978 (acct_on_mutex){+.+.}, at: __x64_sys_acct+0xa6/0x200 kernel/acct.c:273

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1042 Comm: khungtaskd Not tainted 5.1.0-rc1+ #31
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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
 watchdog+0x9b7/0xec0 kernel/hung_task.c:288
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/03/21 08:13 upstream 54c490164523 427ea487 .config console log report ci-upstream-kasan-gce-selinux-root
2019/03/11 10:29 upstream 12ad143e1b80 12365b99 .config console log report ci-upstream-kasan-gce-smack-root
2019/02/12 05:30 upstream aa0c38cf39de 65a0d619 .config console log report ci-upstream-kasan-gce-selinux-root
2018/10/03 23:48 upstream 6bebe37927f3 8b311eaf .config console log report ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.