On Fri, Jan 14, 2011 at 01:57:55PM +1100, Nick Piggin wrote: > On Fri, Jan 14, 2011 at 1:03 AM, J. R. Okajima <hooanon05@xxxxxxxxxxx> wrote: > > > > NFSD calls filesystem's ->d_revalidate() with the parameter nd == NULL. > > So every > > ? ? ? ?if (nd->flags & LOOKUP_RCU) > > ? ? ? ? ? ? ? ?return -ECHILD; > > code which was added to ->d_revalidate() of FS which supports NFS > > exporting will crash. > > > > If we rewrite it as > > ? ? ? ?if (nd && (nd->flags & LOOKUP_RCU)) > > ? ? ? ? ? ? ? ?return -ECHILD; > > the problem may not occur. > > But I am not sure whether lookup_one_len() call in NFSD support rcu-walk. > > Ah, good catch. > > I'm going to change the d_revalidate API so it takes and inode and rcu-walk > flag parameter to make it easier for filesystems to implement rcu-walk. > > That will take care of this NULL nd case. Oh, for fuck sake... Would you at least mind posting your API change description to fsdevel before going for it? ->d_revalidate() is one sick puppy and it's intimately involved in atomic open rewrite. Please, *please* don't make that shit even messier... -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
