kern/92785: Using exported filesystem on OS/2 NFS client causes filesystem freeze

[Ulrich Spoerlein]

The following reply was made to PR kern/92785; it has been noted by GNATS.

From: "Ulrich Spoerlein" <uspoerlein at gmail.com>
To: "Konstantin Belousov" <kostikbel at gmail.com>
Cc: bug-followup at freebsd.org, "Bruce Evans" <bde at zeta.org.au>
Subject: Re: kern/92785: Using exported filesystem on OS/2 NFS client causes filesystem freeze
Date: Wed, 27 Dec 2006 17:05:00 +0100

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 On 12/27/06, Konstantin Belousov <kostikbel at gmail.com> wrote:
 > Index: fs/udf/udf_vnops.c
 > ===================================================================
 > RCS file: /usr/local/arch/ncvs/src/sys/fs/udf/udf_vnops.c,v
 > retrieving revision 1.61
 > diff -u -r1.61 udf_vnops.c
 > --- fs/udf/udf_vnops.c  3 Feb 2006 15:25:52 -0000       1.61
 > +++ fs/udf/udf_vnops.c  27 Dec 2006 15:24:10 -0000
 > @@ -915,7 +915,7 @@
 >                 if (flags & ISDOTDOT)
 >                         VOP_UNLOCK(dvp, 0, a->a_cnp->cn_thread);
 >                 error = udf_vget(udfmp->im_mountp, id, LK_EXCLUSIVE, &tdp);
 > -               if (flags & ISDOTDOT)
 > +               if ((flags & ISDOTDOT) && dvp != tdp )
 >                         vn_lock(dvp, LK_EXCLUSIVE|LK_RETRY, a->a_cnp->cn_thread);
 >                 if (!error) {
 >                         /*
 
 I do NOT have a UDF-Image and can thus not test this change. If some
 kind soul could give me a link to an UDF image < 300MB, that would be
 great.
 
 In addition to ufs, msdosfs and cd9660, I also had to patch ext2fs in
 the same way. NB: Even though reiserfs has a similar code flow, I was
 not able to make a reiserfs exported filesystem hang or crash the
 machine. Odd.
 
 Attached is the cumulative diff of the kernel I tested this with.
 Tested filesystems needing patch: ufs, msdosfs, cd9660, ext2fs
 Tested filesystems sans patch: reiserfs
 Untested filesystems: udf, ntfs, smbfs, nwfs, (zfs?)
 
 All the testing was sponsored by: 1822direkt GmbH
 Thanks for your support.
 
 Uli
 
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