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INFO: task hung in lock_two_nondirectories

Status: auto-closed as invalid on 2019/02/22 12:36
First crash: 2117d, last: 2099d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in lock_two_nondirectories ext4 1 308d 308d 0/26 auto-obsoleted due to no activity on 2023/09/08 04:44

Sample crash report:
INFO: task syz-executor0:6895 blocked for more than 140 seconds.
      Not tainted 4.9.112-g9e79039 #7
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D28440  6895   3867 0x00000004
 ffff8801d8e31800 ffff8801d85b8540 ffff8801b583f480 ffff8801c97d4800
 ffff8801db321c18 ffff88019aba7898 ffffffff839e907d ffffffff81235667
 0000000000000000 ffff8801d8e320c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839ea67f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839f5cb8>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839f5cb8>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee7527>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff8122c290>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff8122c290>] down_write_nested+0x60/0xa0 kernel/locking/rwsem.c:174
 [<ffffffff815cc288>] inode_lock_nested include/linux/fs.h:801 [inline]
 [<ffffffff815cc288>] lock_two_nondirectories+0xb8/0xf0 fs/inode.c:983
 [<ffffffff81596b3a>] vfs_rename2+0x42a/0x18f0 fs/namei.c:4473
 [<ffffffff815af282>] SYSC_renameat2 fs/namei.c:4657 [inline]
 [<ffffffff815af282>] SyS_renameat2 fs/namei.c:4546 [inline]
 [<ffffffff815af282>] SYSC_rename fs/namei.c:4697 [inline]
 [<ffffffff815af282>] SyS_rename+0x612/0x800 fs/namei.c:4695
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f9f53>] 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: [<ffffffff8136675c>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8136675c>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81425de7>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3777:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f8122>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff8211edc2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
3 locks held by syz-executor0/6895:
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff815e0a2f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff815e0a2f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#14/1){+.+.+.}, at: [<ffffffff815940f6>] inode_lock_nested include/linux/fs.h:801 [inline]
 #1:  (&sb->s_type->i_mutex_key#14/1){+.+.+.}, at: [<ffffffff815940f6>] lock_rename+0x236/0x290 fs/namei.c:2857
 #2:  (&sb->s_type->i_mutex_key#14/4){+.+...}, at: [<ffffffff815cc288>] inode_lock_nested include/linux/fs.h:801 [inline]
 #2:  (&sb->s_type->i_mutex_key#14/4){+.+...}, at: [<ffffffff815cc288>] lock_two_nondirectories+0xb8/0xf0 fs/inode.c:983
2 locks held by syz-executor0/6905:
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff815e0a2f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff815e0a2f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#14){++++++}, at: [<ffffffff815a4df5>] inode_lock include/linux/fs.h:766 [inline]
 #1:  (&sb->s_type->i_mutex_key#14){++++++}, at: [<ffffffff815a4df5>] do_last fs/namei.c:3312 [inline]
 #1:  (&sb->s_type->i_mutex_key#14){++++++}, at: [<ffffffff815a4df5>] path_openat+0xed5/0x3590 fs/namei.c:3534
1 lock held by syz-executor0/6946:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d818c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by syz-executor0/6967:
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff815e0a2f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff815e0a2f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#14/1){+.+.+.}, at: [<ffffffff815940f6>] inode_lock_nested include/linux/fs.h:801 [inline]
 #1:  (&sb->s_type->i_mutex_key#14/1){+.+.+.}, at: [<ffffffff815940f6>] lock_rename+0x236/0x290 fs/namei.c:2857

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.112-g9e79039 #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8607d08 ffffffff81eb3249 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9bd0 ffff8801d8607d40
 ffffffff81ebe547 0000000000000001 0000000000000000 0000000000000002
Call Trace:
 [<ffffffff81eb3249>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb3249>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebe547>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebe4da>] 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
 [<ffffffff81366cf4>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366cf4>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366cf4>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366cf4>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0bd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fa11c>] 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
CPU: 0 PID: 1702 Comm: kworker/u4:3 Not tainted 4.9.112-g9e79039 #7
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfnc (flush-7:0)c
task: ffff8801cf5d3000 task.stack: ffff8801cf788000
RIP: 0010:[<ffffffff81f1ac82>] c [<ffffffff81f1ac82>] check_preemption_disabled+0x12/0x170 lib/smp_processor_id.c:12
RSP: 0018:ffff8801cf78f548  EFLAGS: 00000093
RAX: ffff8801cf5d3000 RBX: ffffffff83cce7a0 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff83cce7a0 RDI: ffffffff83e2de20
RBP: ffff8801cf78f568 R08: ffff8801cf5d3960 R09: 0000000000000001
R10: 0000000000000000 R11: 1ffff10039eba727 R12: ffffffff83e2de20
R13: ffffffff83cce7a0 R14: ffff8801b67859d8 R15: 0000000000000004
FS:  0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f70a0735518 CR3: 00000001cb4ee000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801b67859d8c dffffc0000000000c ffff8801b67859d8c 0000000000000004c
 ffff8801cf78f580c ffffffff81f1ae1cc 0000000000000004c ffff8801cf78f5d0c
 ffffffff81624365c 0000020007001e00c 0000000000000041c ffff8801d61c8b80c
Call Trace:
 [<ffffffff81f1ae1c>] __this_cpu_preempt_check+0x1c/0x20 lib/smp_processor_id.c:62
 [<ffffffff81624365>] lookup_bh_lru fs/buffer.c:1327 [inline]
 [<ffffffff81624365>] __find_get_block+0x75/0x4c0 fs/buffer.c:1356
 [<ffffffff81625339>] __getblk_slow fs/buffer.c:1101 [inline]
 [<ffffffff81625339>] __getblk_gfp+0x189/0x710 fs/buffer.c:1386
 [<ffffffff81628cdd>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818cc5db>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818cc5db>] __fat_write_inode+0x2ab/0x980 fs/fat/inode.c:844
 [<ffffffff818d07e9>] fat_write_inode+0x79/0x170 fs/fat/inode.c:893
 [<ffffffff8160232d>] write_inode fs/fs-writeback.c:1180 [inline]
 [<ffffffff8160232d>] __writeback_single_inode+0x86d/0x1020 fs/fs-writeback.c:1379
 [<ffffffff8160362c>] writeback_sb_inodes+0x4ac/0xe70 fs/fs-writeback.c:1584
 [<ffffffff816040eb>] __writeback_inodes_wb+0xfb/0x1e0 fs/fs-writeback.c:1653
 [<ffffffff81604872>] wb_writeback+0x512/0xbd0 fs/fs-writeback.c:1762
 [<ffffffff8160e073>] wb_check_background_flush fs/fs-writeback.c:1843 [inline]
 [<ffffffff8160e073>] wb_do_writeback fs/fs-writeback.c:1902 [inline]
 [<ffffffff8160e073>] wb_workfn+0x723/0xdb0 fs/fs-writeback.c:1930
 [<ffffffff8118d191>] process_one_work+0x7e1/0x1500 kernel/workqueue.c:2092
 [<ffffffff8118df86>] worker_thread+0xd6/0x10a0 kernel/workqueue.c:2226
 [<ffffffff8119d0bd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fa11c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Code: cff cff c48 c8b c85 ce0 cfe cff cff ce9 ce0 cf3 cff cff c66 c2e c0f c1f c84 c00 c00 c00 c00 c00 c90 c55 c48 c89 ce5 c41 c57 c41 c56 c41 c55 c49 c89 cf5 c41 c54 c49 c89 cfc c<53> c48 c83 cec c08 ce8 ce4 c3d c44 cff c65 c8b c1d c95 cb4 c0f c7e c65 c8b c05 cb6 c

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/07/15 08:16 https://android.googlesource.com/kernel/common android-4.9 9e7903954483 92a49505 .config console log report ci-android-49-kasan-gce-root
2018/06/27 09:43 https://android.googlesource.com/kernel/common android-4.9 00a0bcbfcfb6 43e60f7e .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.