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INFO: task hung in vfs_removexattr

Status: auto-closed as invalid on 2019/02/22 13:39
First crash: 2102d, last: 2082d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vfs_removexattr fs 21 1165d 2106d 0/26 closed as dup on 2018/07/18 11:45

Sample crash report:
INFO: task syz-executor0:12616 blocked for more than 140 seconds.
      Not tainted 4.9.116-g0137ea2 #18
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D29088 12616   3703 0x00000004
 ffff8801d7bb1800 ffff8801d8500a80 ffff8801d8500a80 ffff8801d48e0000
 ffff8801db321c18 ffff88019e58f9d8 ffffffff839ead0d ffffffff81235647
 0000000000000000 ffff8801d7bb20c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839ec30f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839f7948>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839f7948>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee8987>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff839f571c>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff839f571c>] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54
 [<ffffffff815efe29>] inode_lock include/linux/fs.h:766 [inline]
 [<ffffffff815efe29>] vfs_removexattr+0x79/0x1a0 fs/xattr.c:392
 [<ffffffff815f0005>] removexattr+0xb5/0x110 fs/xattr.c:695
 [<ffffffff815f0196>] path_removexattr+0x136/0x150 fs/xattr.c:709
 [<ffffffff815f1ee2>] SYSC_removexattr fs/xattr.c:723 [inline]
 [<ffffffff815f1ee2>] SyS_removexattr+0x22/0x30 fs/xattr.c:720
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fbc13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/519:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136677c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136677c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425e07>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3510:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d835c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3606:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f9db2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82120212>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor0/12543:
 #0:  (sb_writers#16){.+.+.+}, at: [<ffffffff815e0bff>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#16){.+.+.+}, at: [<ffffffff815e0bff>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#22){+.+.+.}, at: [<ffffffff815efe29>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#22){+.+.+.}, at: [<ffffffff815efe29>] vfs_removexattr+0x79/0x1a0 fs/xattr.c:392
2 locks held by syz-executor0/12616:
 #0:  (sb_writers#16){.+.+.+}, at: [<ffffffff815e0bff>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#16){.+.+.+}, at: [<ffffffff815e0bff>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#22){+.+.+.}, at: [<ffffffff815efe29>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#22){+.+.+.}, at: [<ffffffff815efe29>] vfs_removexattr+0x79/0x1a0 fs/xattr.c:392

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.116-g0137ea2 #18
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d896fd08 ffffffff81eb46a9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9bd0 ffff8801d896fd40
 ffffffff81ebf9a7 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb46a9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb46a9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebf9a7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebf93a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b9cd4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81366d14>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366d14>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366d14>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366d14>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0ad>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fbddc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff839fa816

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/02 22:19 https://android.googlesource.com/kernel/common android-4.9 0137ea2134c0 5b7e23bb .config console log report ci-android-49-kasan-gce-root
2018/07/14 13:41 https://android.googlesource.com/kernel/common android-4.9 9e7903954483 92a49505 .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.