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INFO: task hung in vfat_lookup

Status: auto-closed as invalid on 2019/02/22 16:49
First crash: 2068d, last: 2057d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in vfat_lookup exfat 38 1919d 2047d 0/26 closed as dup on 2018/09/05 22:07
linux-4.19 INFO: task hung in vfat_lookup 1 561d 561d 0/1 auto-obsoleted due to no activity on 2023/01/28 11:59

Sample crash report:
l2tp_core: tunl 4: closing all sessions...
l2tp_core: tunl 4: closing all sessions...
l2tp_core: tunl 4: closing...
l2tp_core: tunl 4: closing all sessions...
l2tp_core: tunl 4: free...
INFO: task syz-executor0:20127 blocked for more than 140 seconds.
      Not tainted 4.9.124-g09eb2ba #31
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D26776 20127      1 0x00000004
 ffff88019bfcb000 0000000000000000 ffff8801c8dbf9c0 ffff8801d9a6b000
 ffff8801db321c18 ffff88019aa674c8 ffffffff839f0afd ffff88019bfcb8c8
 ffffed00337f9718 ffff88019bfcb000 00fffc0000000000 ffff8801db3224e8
Call Trace:
 [<ffffffff839f20ff>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839f2a83>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff839f6f06>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff839f6f06>] mutex_lock_nested+0x326/0x870 kernel/locking/mutex.c:621
 [<ffffffff818df1b1>] vfat_lookup+0xd1/0x530 fs/fat/namei_vfat.c:729
 [<ffffffff8159953e>] lookup_slow+0x23e/0x470 fs/namei.c:1668
 [<ffffffff815a5ac6>] walk_component+0x716/0x1bb0 fs/namei.c:1784
 [<ffffffff815a77e9>] link_path_walk+0x889/0x1200 fs/namei.c:2120
 [<ffffffff815a885d>] path_openat+0x1ad/0x3590 fs/namei.c:3533
 [<ffffffff815aff07>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff815726dd>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff815729bd>] SYSC_open fs/open.c:1090 [inline]
 [<ffffffff815729bd>] SyS_open+0x2d/0x40 fs/open.c:1085
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff83a019d3>] 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: [<ffffffff813689dc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813689dc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.?..}, at: [<ffffffff81428248>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by rs:main Q:Reg/3662:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815dc7ec>] __fdget_pos+0xac/0xd0 fs/file.c:781
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff8157745e>] file_start_write include/linux/fs.h:2640 [inline]
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff8157745e>] vfs_write+0x3ae/0x530 fs/read_write.c:556
2 locks held by getty/3760:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839ffba2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff82125402>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor0/20127:
 #0:  (&sb->s_type->i_mutex_key#22){++++++}, at: [<ffffffff81599441>] inode_lock_shared include/linux/fs.h:776 [inline]
 #0:  (&sb->s_type->i_mutex_key#22){++++++}, at: [<ffffffff81599441>] lookup_slow+0x141/0x470 fs/namei.c:1645
 #1:  (&sbi->s_lock){+.+.+.}, at: [<ffffffff818df1b1>] vfat_lookup+0xd1/0x530 fs/fat/namei_vfat.c:729

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

NMI backtrace for cpu 1
CPU: 1 PID: 519 Comm: khungtaskd Not tainted 4.9.124-g09eb2ba #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d95efd08 ffffffff81eb95e9 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810b9fa0 ffff8801d95efd40
 ffffffff81ec4927 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb95e9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb95e9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ec4927>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ec48ba>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810ba0a4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81368f74>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81368f74>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81368f74>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81368f74>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01b9c>] 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: 27151 Comm: syz-executor0 Not tainted 4.9.124-g09eb2ba #31
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801ccc68000 task.stack: ffff8801a2ed0000
RIP: 0010:[<ffffffff81360d2b>] c [<ffffffff81360d2b>] __read_once_size include/linux/compiler.h:243 [inline]
RIP: 0010:[<ffffffff81360d2b>] c [<ffffffff81360d2b>] __sanitizer_cov_trace_pc+0x3b/0x50 kernel/kcov.c:105
RSP: 0018:ffff8801a2ed7268  EFLAGS: 00000246
RAX: 0000000000040000 RBX: dffffc0000000000 RCX: ffffc9000d7e1000
RDX: 000000000003ffff RSI: ffffffff816260c1 RDI: ffff8801cbdf55f0
RBP: ffff8801a2ed7268 R08: ffff8801ccc68938 R09: 0000000000000001
R10: 0000000000000000 R11: 1ffff1003998d122 R12: 0000000000000044
R13: ffff8801cbdf5348 R14: ffff8801d9c105c0 R15: ffff8801cbdf5540
FS:  00007f77fd05c700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f34197dd000 CR3: 00000001cb0b7000 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Stack:
 ffff8801a2ed72b8c ffffffff816260c1c 0000000008100000c 0000000000000001c
 0000000000040800c 0000000000000003c 0000000000000200c ffffea00071a3840c
 0000000000000200c dffffc0000000000c ffff8801a2ed7358c ffffffff81629ed9c
Call Trace:
 [<ffffffff816260c1>] init_page_buffers+0x251/0x350 fs/buffer.c:969
 [<ffffffff81629ed9>] grow_dev_page fs/buffer.c:1014 [inline]
 [<ffffffff81629ed9>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff81629ed9>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff81629ed9>] __getblk_gfp+0x579/0x710 fs/buffer.c:1386
 [<ffffffff8162d48d>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818bc678>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818bc678>] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100
 [<ffffffff818c4477>] fat_get_entry fs/fat/dir.c:128 [inline]
 [<ffffffff818c4477>] fat_search_long+0x277/0x1180 fs/fat/dir.c:477
 [<ffffffff818de9e4>] vfat_find+0x134/0x180 fs/fat/namei_vfat.c:708
 [<ffffffff818df1c1>] vfat_lookup+0xe1/0x530 fs/fat/namei_vfat.c:731
 [<ffffffff8159f93d>] lookup_open+0x63d/0x1930 fs/namei.c:3203
 [<ffffffff815a9eb3>] do_last fs/namei.c:3315 [inline]
 [<ffffffff815a9eb3>] path_openat+0x1803/0x3590 fs/namei.c:3534
 [<ffffffff815aff07>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff815726dd>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff815729bd>] SYSC_open fs/open.c:1090 [inline]
 [<ffffffff815729bd>] SyS_open+0x2d/0x40 fs/open.c:1085
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff83a019d3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c4c c70 ccb c7e c81 ce2 c00 c01 c1f c00 c48 c8b c75 c08 c75 c2b c8b c90 c80 c12 c00 c00 c83 cfa c02 c75 c20 c48 c8b c88 c88 c12 c00 c00 c8b c80 c84 c12 c00 c00 c48 c8b c11 c<48> c83 cc2 c01 c48 c39 cd0 c76 c07 c48 c89 c34 cd1 c48 c89 c11 c5d cc3 c0f c1f c00 c

Crashes (13):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/26 16:47 https://android.googlesource.com/kernel/common android-4.9 09eb2ba5ed0c 758cd203 .config console log report ci-android-49-kasan-gce-root
2018/08/26 07:12 https://android.googlesource.com/kernel/common android-4.9 09eb2ba5ed0c 758cd203 .config console log report ci-android-49-kasan-gce-root
2018/08/25 05:29 https://android.googlesource.com/kernel/common android-4.9 6a1b5923548a 9b0f5c75 .config console log report ci-android-49-kasan-gce-root
2018/08/24 20:35 https://android.googlesource.com/kernel/common android-4.9 6a1b5923548a 9b0f5c75 .config console log report ci-android-49-kasan-gce-root
2018/08/24 18:59 https://android.googlesource.com/kernel/common android-4.9 6a1b5923548a 9b0f5c75 .config console log report ci-android-49-kasan-gce-root
2018/08/23 09:01 https://android.googlesource.com/kernel/common android-4.9 8dd3fc2ed765 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/23 07:36 https://android.googlesource.com/kernel/common android-4.9 8dd3fc2ed765 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/22 07:35 https://android.googlesource.com/kernel/common android-4.9 8dd3fc2ed765 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/22 07:06 https://android.googlesource.com/kernel/common android-4.9 8dd3fc2ed765 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/21 17:07 https://android.googlesource.com/kernel/common android-4.9 54068d61e7d8 95b5c82b .config console log report ci-android-49-kasan-gce-root
2018/08/15 14:25 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 9ccc1d45 .config console log report ci-android-49-kasan-gce-root
2018/08/15 10:54 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 9ccc1d45 .config console log report ci-android-49-kasan-gce-root
2018/08/15 10:05 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 0e6dcb88 .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.