Re: page fault in ufs_fhtovp

[David Holland <dholland-tech%netbsd.org@localhost>]

On Mon, May 26, 2014 at 12:43:32PM +0200, Manuel Bouyer wrote:
 > >              if ((error = VFS_VGET(mp, ufhp->ufid_ino, &nvp)) != 0) {
 > >                      *vpp = NULLVP;
 > >                      return (error);
 > >              }
 > >              ip = VTOI(nvp);
 > >              KASSERT(ip != NULL);
 > > -->          if (ip->i_mode == 0 || ip->i_gen != ufhp->ufid_gen) {
 > > 
 > > Looks like the KASSERT should have caught it (in a DIAGNOSTIC kernel).
 > > VTOI returned NULL?
 > 
 > Probably. I've already fixed races like this (between fhtovp() and reclaim)
 > in the past, but I guess there are some more ... Not easy to track down.

The new vnode cache in -current should eliminate this problem once and
for all... not that this helps 6.1.

-- 
David A. Holland
dholland%netbsd.org@localhost