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INFO: task hung in do_rmdir

Status: auto-closed as invalid on 2019/02/22 12:59
First crash: 2166d, last: 2166d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_rmdir (5) ext4 nilfs 5 460d 627d 0/26 auto-obsoleted due to no activity on 2023/04/25 17:21
upstream INFO: task hung in do_rmdir (3) fs 10 1141d 1216d 0/26 auto-closed as invalid on 2021/06/01 08:24
linux-4.19 INFO: task hung in do_rmdir 1 644d 644d 0/1 auto-obsoleted due to no activity on 2022/11/10 04:55
upstream INFO: task hung in do_rmdir (4) fs 1 800d 800d 0/26 auto-closed as invalid on 2022/05/08 10:41
upstream INFO: task hung in do_rmdir (2) exfat 3 1924d 2059d 0/26 closed as dup on 2018/09/11 15:01
upstream INFO: task hung in do_rmdir fs 1 2213d 2213d 0/26 closed as invalid on 2018/03/27 11:14

Sample crash report:
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
b_state=0x00000029, b_size=512
device loop0 blocksize: 4096
__find_get_block_slow() failed. block=1, b_blocknr=8
INFO: task syz-executor0:16398 blocked for more than 120 seconds.
      Not tainted 4.9.99-gc2f9bce #22
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor0   D29696 16398  12389 0x00000004
 ffff8801d840b000 0000000000000000 ffff88018b34df80 ffffffff84629800
 ffff8801db221b98 ffff8801bda8fb08 ffffffff839e377d ffffffff81233817
 0000000000000000 ffff8801d840b8c0 0000000600000007 ffff8801db222468
Call Trace:
 [<ffffffff839e4d7f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3557
 [<ffffffff839f03b8>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff839f03b8>] rwsem_down_write_failed+0x598/0x990 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81ee51e7>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff8122a440>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff8122a440>] down_write_nested+0x60/0xa0 kernel/locking/rwsem.c:174
 [<ffffffff815a7d53>] inode_lock_nested include/linux/fs.h:801 [inline]
 [<ffffffff815a7d53>] do_rmdir+0x293/0x3f0 fs/namei.c:3939
 [<ffffffff815aa02b>] SYSC_unlinkat fs/namei.c:4121 [inline]
 [<ffffffff815aa02b>] SyS_unlinkat+0x5b/0x80 fs/namei.c:4115
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f4653>] 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: [<ffffffff813646ec>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff813646ec>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff81423bc0>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/3683:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff815d567c>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/3779:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff839f2822>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+.+.}, at: [<ffffffff8211cc32>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2133
2 locks held by syz-executor0/16398:
 #0:  (sb_writers#21){.+.+.+}, at: [<ffffffff815ddf1f>] sb_start_write include/linux/fs.h:1573 [inline]
 #0:  (sb_writers#21){.+.+.+}, at: [<ffffffff815ddf1f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&sb->s_type->i_mutex_key#25/1){+.+...}, at: [<ffffffff815a7d53>] inode_lock_nested include/linux/fs.h:801 [inline]
 #1:  (&sb->s_type->i_mutex_key#25/1){+.+...}, at: [<ffffffff815a7d53>] do_rmdir+0x293/0x3f0 fs/namei.c:3939

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

NMI backtrace for cpu 0
CPU: 0 PID: 519 Comm: khungtaskd Not tainted 4.9.99-gc2f9bce #22
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d8affd08 ffffffff81eb0f09 0000000000000000 0000000000000000
 0000000000000000 0000000000000001 ffffffff810b7da0 ffff8801d8affd40
 ffffffff81ebc207 0000000000000000 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81eb0f09>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb0f09>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81ebc207>] nmi_cpu_backtrace.cold.2+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81ebc19a>] nmi_trigger_cpumask_backtrace+0x12a/0x14f lib/nmi_backtrace.c:60
 [<ffffffff810b7ea4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff81364c84>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff81364c84>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff81364c84>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff81364c84>] watchdog+0x6b4/0xa20 kernel/hung_task.c:239
 [<ffffffff8119ad5d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff839f481c>] 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: 16392 Comm: syz-executor0 Not tainted 4.9.99-gc2f9bce #22
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801d7d71800 task.stack: ffff88018b000000
RIP: 0010:[<ffffffff8214d58b>] c [<ffffffff8214d58b>] inb arch/x86/include/asm/io.h:316 [inline]
RIP: 0010:[<ffffffff8214d58b>] c [<ffffffff8214d58b>] io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:414
RSP: 0018:ffff88018b006f30  EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffffff8214d531 RDI: ffffffff864aae78
RBP: ffff88018b006f40 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff864aae40
R13: 0000000000000020 R14: fffffbfff0c9560f R15: fffffbfff0c955d1
FS:  00007fa62f077700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000214a000 CR3: 000000018ae97000 CR4: 00000000001606f0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Stack:
 ffffffff864aae40c 000000000000270cc ffff88018b006f90c ffffffff8214f154c
 ffffffff81edc1f8c ffffffff864aae88c ffffffff864ab07ac ffffffff864aae40c
 000000000000006fc ffffffff8214f2a0c dffffc0000000000c 000000000000006fc
Call Trace:
 [<ffffffff8214f154>] serial_in drivers/tty/serial/8250/8250.h:111 [inline]
 [<ffffffff8214f154>] wait_for_xmitr+0x94/0x1e0 drivers/tty/serial/8250/8250_port.c:1997
 [<ffffffff8214f2bf>] serial8250_console_putchar+0x1f/0x60 drivers/tty/serial/8250/8250_port.c:3103
 [<ffffffff82137ae9>] uart_console_write+0x59/0xf0 drivers/tty/serial/serial_core.c:1859
 [<ffffffff8215b4c8>] serial8250_console_write+0x528/0x820 drivers/tty/serial/8250/8250_port.c:3169
 [<ffffffff8214803f>] univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:594
 [<ffffffff81259e7d>] call_console_drivers.isra.18.constprop.28+0x1ad/0x360 kernel/printk/printk.c:1589
 [<ffffffff8125cc7f>] console_unlock+0x42f/0xb40 kernel/printk/printk.c:2449
 [<ffffffff8125d7d8>] vprintk_emit+0x448/0x790 kernel/printk/printk.c:1903
 [<ffffffff8125db48>] vprintk+0x28/0x30 kernel/printk/printk.c:1913
 [<ffffffff8125db6d>] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1914
 [<ffffffff8142a995>] vprintk_func kernel/printk/internal.h:36 [inline]
 [<ffffffff8142a995>] printk+0xaf/0xd7 kernel/printk/printk.c:1975
 [<ffffffff81cb748a>] __find_get_block_slow.cold.57+0x37/0xf0 fs/buffer.c:238
 [<ffffffff81621a5e>] __find_get_block+0x23e/0x4c0 fs/buffer.c:1360
 [<ffffffff81622869>] __getblk_slow fs/buffer.c:1101 [inline]
 [<ffffffff81622869>] __getblk_gfp+0x189/0x710 fs/buffer.c:1386
 [<ffffffff8162620d>] __bread_gfp+0x2d/0x270 fs/buffer.c:1420
 [<ffffffff818b3f88>] sb_bread include/linux/buffer_head.h:300 [inline]
 [<ffffffff818b3f88>] fat__get_entry+0x4c8/0x8f0 fs/fat/dir.c:100
 [<ffffffff818b6c11>] fat_get_entry fs/fat/dir.c:128 [inline]
 [<ffffffff818b6c11>] fat_get_short_entry+0x131/0x2a0 fs/fat/dir.c:876
 [<ffffffff818b716d>] fat_scan+0xfd/0x340 fs/fat/dir.c:961
 [<ffffffff818de779>] msdos_find+0xf9/0x2d0 fs/fat/namei_msdos.c:128
 [<ffffffff818df095>] msdos_lookup+0x135/0x250 fs/fat/namei_msdos.c:208
 [<ffffffff815988bd>] lookup_open+0x63d/0x1930 fs/namei.c:3203
 [<ffffffff815a2e33>] do_last fs/namei.c:3315 [inline]
 [<ffffffff815a2e33>] path_openat+0x1803/0x3590 fs/namei.c:3534
 [<ffffffff815a8e87>] do_filp_open+0x197/0x270 fs/namei.c:3568
 [<ffffffff8156b65d>] do_sys_open+0x30d/0x5c0 fs/open.c:1072
 [<ffffffff8156b980>] SYSC_openat fs/open.c:1099 [inline]
 [<ffffffff8156b980>] SyS_openat+0x30/0x40 fs/open.c:1093
 [<ffffffff81006316>] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282
 [<ffffffff839f4653>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: c24 cc9 c00 c00 c00 c49 c8d c7c c24 c38 c48 cb8 c00 c00 c00 c00 c00 cfc cff cdf c48 c89 cfa c48 cc1 cea c03 cd3 ce3 c80 c3c c02 c00 c75 c17 c41 c03 c5c c24 c38 c89 cda cec c<5b> c0f cb6 cc0 c41 c5c c5d cc3 ce8 c68 cbd c3e cff ceb cc2 ce8 cc1 cbd c3e cff ceb c

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/05/12 22:24 https://android.googlesource.com/kernel/common android-4.9 c2f9bce9fee8 e726f42b .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.