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INFO: task hung in grab_super

Status: auto-closed as invalid on 2019/02/22 13:19
First crash: 1943d, last: 1943d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-414 INFO: task hung in grab_super 4 1866d 1704d 0/1 auto-closed as invalid on 2019/04/28 15:34
linux-4.14 INFO: task hung in grab_super C error 241 379d 1695d 0/1 upstream: reported C repro on 2019/04/19 12:37
android-414 INFO: task hung in grab_super (2) 2 1605d 1626d 0/1 auto-closed as invalid on 2019/11/15 12:55
upstream INFO: task hung in grab_super udf C 209 321d 1970d 0/25 closed as dup on 2018/07/18 11:42
linux-4.19 INFO: task hung in grab_super vfs udf C error 249 302d 1696d 0/1 upstream: reported C repro on 2019/04/18 03:33
upstream INFO: task hung in grab_super (2) fs 1 185d 185d 0/25 auto-obsoleted due to no activity on 2023/09/05 02:19
android-49 INFO: task hung in grab_super (2) 1 1571d 1571d 0/3 auto-closed as invalid on 2019/12/19 00:51

Sample crash report:
INFO: task syz-executor3:8368 blocked for more than 140 seconds.
      Not tainted 4.9.119-g9dc978d #23
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D29384  8368   3884 0x00000004
 ffff8801b5efc800 ffff8801ca81df80 ffff8801ca81df80 ffff8801979f0000
 ffff8801db321c18 ffff8801b795f8a8 ffffffff839ebdcd ffffffff81235627
 0000000000000000 ffff8801b5efd0c0 0000000600000007 ffff8801db3224e8
Call Trace:
 [<ffffffff839ed3cf>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff839f8a08>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839f8a08>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee8ec7>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff839f67dc>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff839f67dc>] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54
 [<ffffffff8157ac4c>] grab_super+0x5c/0x170 fs/super.c:364
 [<ffffffff8157bb01>] sget_userns+0x2b1/0xba0 fs/super.c:491
 [<ffffffff8157c4c6>] sget+0xd6/0x120 fs/super.c:559
 [<ffffffff8157c6f6>] mount_bdev+0xe6/0x390 fs/super.c:1073
 [<ffffffff817ac6f4>] ext4_mount+0x34/0x40 fs/ext4/super.c:5614
 [<ffffffff8157e65c>] mount_fs+0x28c/0x370 fs/super.c:1206
 [<ffffffff815dde81>] vfs_kern_mount.part.29+0xd1/0x3d0 fs/namespace.c:991
 [<ffffffff815e57a9>] vfs_kern_mount fs/namespace.c:973 [inline]
 [<ffffffff815e57a9>] do_new_mount fs/namespace.c:2513 [inline]
 [<ffffffff815e57a9>] do_mount+0x3c9/0x2740 fs/namespace.c:2835
 [<ffffffff815e84fe>] SYSC_mount fs/namespace.c:3051 [inline]
 [<ffffffff815e84fe>] SyS_mount+0xfe/0x110 fs/namespace.c:3028
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fccd3>] 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: [<ffffffff813667bc>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813667bc>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81426027>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
2 locks held by getty/3780:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839fae72>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff821208d2>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor3/8368:
 #0:  (&bdev->bd_fsfreeze_mutex){+.+.+.}, at: [<ffffffff8157c696>] mount_bdev+0x86/0x390 fs/super.c:1067
 #1:  (&type->s_umount_key#47){+.+...}, at: [<ffffffff8157ac4c>] grab_super+0x5c/0x170 fs/super.c:364

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

NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.119-g9dc978d #23
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d85cfd08 ffffffff81eb4be9 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b9bd0 ffff8801d85cfd40
 ffffffff81ebfee7 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb4be9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb4be9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebfee7>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebfe7a>] 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
 [<ffffffff81366d54>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81366d54>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81366d54>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81366d54>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119d0ed>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839fce9c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8356 Comm: syz-executor3 Not tainted 4.9.119-g9dc978d #23
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801c0ee4800 task.stack: ffff880197af8000
RIP: 0010:[<ffffffff8127bebb>] c [<ffffffff8127bebb>] debug_lockdep_rcu_enabled.part.2+0xb/0x60 kernel/rcu/update.c:262
RSP: 0018:ffff880197aff7e0  EFLAGS: 00000202
RAX: dffffc0000000000 RBX: ffff8801cbfb8f08 RCX: 0000000000000000
RDX: 0000000000000004 RSI: ffff8801c0ee50f0 RDI: ffffffff84870b00
RBP: ffff880197aff7f0 R08: ffff8801c0ee5110 R09: 0000000000000001
R10: ffff8801c0ee4800 R11: 1ffff100381dca1d R12: 0000000000000007
R13: dffffc0000000000 R14: 0000000002420840 R15: ffff8801cbfb8f08
FS:  00007fa935548700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f51b4c83000 CR3: 00000001cd06c000 CR4: 00000000001606f0
Stack:
 ffff880197aff7f0c ffffffff8127bf87c ffff880197aff858c ffffffff81438ebfc
 ffffffff81438e70c ffffffff81624533c ffff8801cbfb8dd4c 0000000000000000c
 ffff8801cbfb8b80c 000000000000000fc 0000000000000002c 0000000000000007c
Call Trace:
 [<ffffffff81438ebf>] rcu_read_lock include/linux/rcupdate.h:876 [inline]
 [<ffffffff81438ebf>] find_get_entry+0x4f/0x540 mm/filemap.c:1090
 [<ffffffff8143a2eb>] pagecache_get_page+0x4b/0x720 mm/filemap.c:1201
 [<ffffffff81625809>] find_or_create_page include/linux/pagemap.h:309 [inline]
 [<ffffffff81625809>] grow_dev_page fs/buffer.c:1005 [inline]
 [<ffffffff81625809>] grow_buffers fs/buffer.c:1078 [inline]
 [<ffffffff81625809>] __getblk_slow fs/buffer.c:1105 [inline]
 [<ffffffff81625809>] __getblk_gfp+0x249/0x710 fs/buffer.c:1386
 [<ffffffff816290ed>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff817d0c26>] sb_bread_unmovable include/linux/buffer_head.h:306 [inline]
 [<ffffffff817d0c26>] ext4_fill_super+0x576/0xb490 fs/ext4/super.c:3434
 [<ffffffff8157c8d7>] mount_bdev+0x2c7/0x390 fs/super.c:1100
 [<ffffffff817ac6f4>] ext4_mount+0x34/0x40 fs/ext4/super.c:5614
 [<ffffffff8157e65c>] mount_fs+0x28c/0x370 fs/super.c:1206
 [<ffffffff815dde81>] vfs_kern_mount.part.29+0xd1/0x3d0 fs/namespace.c:991
 [<ffffffff815e57a9>] vfs_kern_mount fs/namespace.c:973 [inline]
 [<ffffffff815e57a9>] do_new_mount fs/namespace.c:2513 [inline]
 [<ffffffff815e57a9>] do_mount+0x3c9/0x2740 fs/namespace.c:2835
 [<ffffffff815e84fe>] SYSC_mount fs/namespace.c:3051 [inline]
 [<ffffffff815e84fe>] SyS_mount+0xfe/0x110 fs/namespace.c:3028
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839fccd3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c00 ce9 c3e cff cff cff c4c c89 cef ce8 c62 c00 c2c c00 ce9 c77 cff cff cff c48 c89 cdf ce8 c55 c00 c2c c00 ce9 ca7 cfe cff cff c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c55 c<48> c89 ce5 c53 c65 c48 c8b c1c c25 cc0 c7d c01 c00 c48 c8d cbb cc4 c08 c00 c00 c48 c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/08/13 17:59 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 7a88b141 .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.