Re: CVS commit: src/sys/kern

[Andrew Doran <ad%netbsd.org@localhost>]

On Wed, Nov 12, 2008 at 06:22:06PM +0100, Reinoud Zandijk wrote:

> > > Committed By:     reinoud
> > > Date:             Tue Nov  4 16:08:41 UTC 2008
> > > 
> > > Modified Files:
> > >   src/sys/kern: vfs_bio.c
> > > 
> > > Log Message:
> > > Don't dereference bp->b_vp->v_mount if its vnode type is VT_VNON. I dont
> > > know if this masks a bug but with a machine having a ffs+wapbl mount, NFS
> > > mounts and a ntfs mount this paniced the machine on suspend.

This change is wrong because it masks a bug. However, it looks like the code
does not work properly in the first instance, and we are going to remove
softdep, so it doesn't matter.

> > Where's the PR describing the actual problem?
> 
> There is no PR (yet); On suspend, all buffers on the bufhashtbl are 
> visited and if they are mounted with softdep an action is taken.
> 
> During this visit, a buffer came by that was NOT assigned to a particular 
> FS i.e. bp->b_vp->v_tag == VT_VNON. This buffer's bp->b_vp->v_mount was NOT 
> NULL though but rather typically 0x40 and so the bp->b_vp->v_mount check 
> failed.

Did you find out why it was 0x40? That's definitley a bug...
 
Andrew