Date: Thu, 13 Jul 2017 12:11:29 -0700 (PDT) From: "Rodney W. Grimes" <freebsd@pdx.rh.CN85.dnsmgr.net> To: John Baldwin <jhb@freebsd.org> Cc: Ian Lepore <ian@freebsd.org>, Edward Tomasz Napierala <trasz@freebsd.org>, rgrimes@freebsd.org, src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r320803 - head/sbin/mount Message-ID: <201707131911.v6DJBTMC090066@pdx.rh.CN85.dnsmgr.net> In-Reply-To: <5242112.0aHCQARnit@ralph.baldwin.cx>
next in thread | previous in thread | raw e-mail | index | archive | help
> On Tuesday, July 11, 2017 02:35:15 PM Ian Lepore wrote: > > I think the docs on this are pretty clear... under -u it says: > > > > The set of options is determined by applying the options specified > > in the argument to -o and finally applying the -r or -w option. > > > > To me, that says that nothing in /etc/fstab is germane to mount -u > > unless one of the other args to mount -u is -o fstab. > > > > This change (r320803) seems like an acceptable workaround, but I think > > the correct long term fix would be to not even open /etc/fstab on mount > > -u without -o fstab. But that may be harder to do than to say; I still > > haven't actually looked at the code involved. > > I concur with this. I've always viewed '-u' as meaning "apply a delta > to the current configuration", not "add this delta to the fstab options > and then apply that entire set of options". In practice, it seems that > it doesn't do either of those, but instead it seems to treats the options > passed to -o as the entire list of options. This is perhaps a bit > surprising. > > For example, suppose you had this: > > /etc/fstab: > > /dev/md0 /bar ufs ro,noauto,noexec 0 0 ... To shed some light on all of this I did the dig to find the original documentaton on mount -u, which actually makes it rather clear what and how things should be happening. Somehow this has been lost over the years: csrg change to mount.c adding -u https://svnweb.freebsd.org/csrg/sbin/mount/mount.c?r1=39329&r2=39333 csrg change to mount.8 documenting -u https://svnweb.freebsd.org/csrg/sbin/mount/mount.8?r1=39328&r2=39466 This documenting of -u clearly states that /etc/fstab shall be consulted during a mount -u, some place we lost that. -- Rod Grimes rgrimes@freebsd.org
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201707131911.v6DJBTMC090066>