kernel panic with unmount: dangling vnode on boot

Ean Kingston ean at
Wed Jun 1 15:21:40 GMT 2005

Hi all,

I just updated my 5.3 system to 5.4p1 from source and ran into a 
serious problem. During boot, when the filesystems are being mounted, 
the system goes into a kernel panic and reports "panic unmount: 
dangling vnode" it then reboots.

I have found PR 79665 which appears to be related.

I have also found that booting to single user mode and manually 
mounting the filesystems will bypass this problem but it is not a good 
workaround since I don't have battery backup and the power here is less 
than ideal (short outages 3 or 4 times a year).

The system this is being tested on is using gvinum for a number of 
filesystems: /tmp is stripped, /home is mirrored, / /var /usr are 
ordinary filesystems.

The system is a dual PIII so I'm using an SMP kernel. I've stripped 
unused device drivers and added a few things so I will re-try with 
generic and generic+smp when I get a chance.

Once I get the system back up (after the most recent reboot) I will 
build a generic kernel and see if that has the same problem.

Does anyone else have similar problems and, if so, are there any 
workarounds so that I can boot cleanly. I really don't want to lose 
gvinum but I will if I have to.

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