Re: ufs_dirbad: /mnt: bad dir ino 50626 at offset 0: mangled entry

From: mike tancsa <mike_at_sentex.net>
Date: Fri, 22 Oct 2021 15:33:22 UTC
On 10/22/2021 11:21 AM, Mark Johnston wrote:
> On Fri, Oct 22, 2021 at 10:36:01AM -0400, mike tancsa wrote:
>> After cycles of this, unmounts, mounts etc, I get
>>
>>
>> panic: ufs_dirbad: /mnt: bad dir ino 50626 at offset 0: mangled entry
>> cpuid = 1
>> time = 1634912598
>> KDB: stack backtrace:
>> #0 0xffffffff80c77035 at kdb_backtrace+0x65
>> #1 0xffffffff80c28a47 at vpanic+0x187
>> #2 0xffffffff80c288b3 at panic+0x43
>> #3 0xffffffff80f345f7 at ufs_lookup_ino+0xdc7
>> #4 0xffffffff80ceae1d at vfs_cache_lookup+0xad
>> #5 0xffffffff80cf872c at lookup+0x46c
>> #6 0xffffffff80cf785c at namei+0x26c
>> #7 0xffffffff80d1c979 at vn_open_cred+0x509
>> #8 0xffffffff80d12a3e at kern_openat+0x26e
>> #9 0xffffffff810b4d3c at amd64_syscall+0x10c
>> #10 0xffffffff8108bdab at fast_syscall_common+0xf8
>> Uptime: 4m48s
>>
>> I forced an fsck on reboot, and the file system is clean. I also deleted
>> /mnt and recreated the directory and still get this issue.  Any idea
>> what might be causing it or how I can better track it down ?
> Is the VM image stored on ZFS?  Which kernel revision is the host running?

Hi,

     The VM is in an Ubuntu host / KVM (Linux ubuntu1 5.11.0-38-generic 
#42-Ubuntu SMP Fri Sep 24 ) with the VM image stored on its local zfs 
file system. Do you think its some strange interaction with the 
hypervisor ? The FreeBSD guest VM is RELENG_13 as of this morning, 
GENERIC kernel stable/13-d8359af5b

     ---Mike