svn commit: r270183 - head/usr.sbin/mountd

[Garrett Cooper]

On Tue, Aug 19, 2014 at 2:04 PM, Bryan Drewery <bdrewery at freebsd.org> wrote:
> Author: bdrewery
> Date: Tue Aug 19 21:04:31 2014
> New Revision: 270183
> URL: http://svnweb.freebsd.org/changeset/base/270183
>
> Log:
>   Avoid showing stale errors when nmount(2) fails.
>
>   Sometimes nmount(2) will fail without setting errmsg. The previous (ignored)
>   error would then be shown as the reason for the failed call if the next
>   nmount(2) also fails without [ENOENT,ENOTSUP].
>
>   An example is when there is a tmpfs mounted with -o size. vfs_filteropt() adds
>   'size' as an error in errmsg due to 'size' not being in tmpfs_updateopts. Then
>   tmpfs_mount returns [ENOTSUP] from nmount(2), which is then ignored. The next
>   call may race with an unmount causing an invalid [EINVAL] that then does log an
>   error, with the tmpfs errmsg.
>
>   The race itself is a separate issue to fix as it is expected to have an
>   [ENOENT] returned instead.
>
>   In this example the mount being shown is actually nullfs, not tmpfs that the
>   error is from.
>
>     mountd[740]: can't delete exports for /poudriere/data/.m/exp-head-commit-test-devel/04/.npkg: Invalid argument mount option <size> is unknown
>
>   It should only show:
>
>     mountd[740]: can't delete exports for /poudriere/data/.m/exp-head-commit-test-devel/04/.npkg: Invalid argument
>
>   MFC after:    2 weeks

Hmm -- I wonder if this is related to
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=191218 ... Guess I
get to retest that bug after this commit :)!