On 5 February 2013 04:13, Rick Macklem <rmack...@uoguelph.ca> wrote: > Sergey Kandaurov wrote: >> On 4 February 2013 06:32, Rick Macklem <rmack...@uoguelph.ca> wrote: >> > Konstantin Belousov wrote: >> >> On Sat, Feb 02, 2013 at 09:30:39PM -0500, Rick Macklem wrote: >> >> > Andriy Gapon wrote: >> >> > > on 31/01/2013 15:29 Sergey Kandaurov said the following: >> >> > > > Hi. >> >> > > > >> >> > > > Got this assertion on idle NFS server while `ls -la >> >> > > > /.zfs/shares/' >> >> > > > issued on NFS client. >> > Ok, here's a snippet of zfs_dirlook() from zfs_dir.c: >> > 388 } else if (name[0] == '.' && name[1] == '.' && name[2] == 0) { >> > 389 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; >> > 390 >> > 391 /* >> > 392 * If we are a snapshot mounted under .zfs, return >> > 393 * the vp for the snapshot directory. >> > 394 */ >> > 395 if ((error = sa_lookup(dzp->z_sa_hdl, >> > 396 SA_ZPL_PARENT(zfsvfs), &parent, sizeof (parent))) != 0) >> > 397 return (error); >> > 398 if (parent == dzp->z_id && zfsvfs->z_parent != zfsvfs) { >> > 399 error = zfsctl_root_lookup(zfsvfs->z_parent->z_ctldir, >> > 400 "snapshot", vpp, NULL, 0, NULL, kcred, >> > 401 NULL, NULL, NULL); >> > 402 return (error); >> > 403 } >> > >> > Just reading the comment, I don't know what it is referring to by >> > "snapshot directory". Would that be "shares" for Sergey's case? >> > >> > It seems too obvious, but maybe the lookup of ".." is returning the >> > vnode for /.zfs/shares for this case? >> > >> > I don't know why this wouldn't have shown up before, but maybe it >> > usually >> > replies from its cache (I think zfs_lookup() calls it a "fast >> > path"). >> > >> > It might still be interesting to replace zfs_vnops.c line# 1451 >> > with: >> > if ((cnp->cn_flags & ISDOTDOT) && *vpp != dvp) >> > and see what happens? >> > >> >> With this change `ls /home/user1001/.zfs/shares/' lists empty >> directory >> (although the relevant dataset has snapshot, but that's a different >> story :)). >> Great! >> Nothing panics/asserts/etc, just seemingly unrelated LOR >> > Yes, I think the patch is relatively safe, since lookup() checks for > same vnode and does a vrele() instead of a vput() when they are the same, > at least for a plain lookup without wantparent. > > So, since I've never used ZFS, what does a "ls -la > /home/user1001/.zfs/shares/" > give you when done locally one the server?
On server (with unmodified kernel): # ls -la /pool1/user1001/.zfs/share total 2 dr-xr-xr-x 2 root wheel 2 Feb 2 20:06 . dr-xr-xr-x 4 root wheel 4 Feb 2 20:06 .. It crashes only when .zfs/share is accessed via NFS (with and without snapshots), and not when accessed locally. -- wbr, pluknet _______________________________________________ freebsd-current@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-current To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"