Hi, On Mon, Mar 04, 2013 at 12:27:05PM +0100, Balint Reczey wrote: > os-prober uses 'mount -o ro', or grub-mount from 1.45: > > commit 7ed9dec4d2c65056f211324f8e25a4d913b0f2a1 > Author: Colin Watson <cjwat...@debian.org> > Date: Fri Apr 8 17:39:32 2011 +0100 > > Use grub-mount if it exists. This lets us do true read-only mounts, > and works better on journalling filesystems that were mounted uncleanly. > > It does practically everything to avoid file system corruption thus I > think this bug should be either closed or moved to mount package to > provide a true read-only option if '-o ro' > is not enough.
Is there still a reason to keep trying the regular mount? Are there cases where grub-mount is expected to fail? Maybe only trying grub-mount could be the default. Also, why did grub-mount fail in this case? Was grub-common not installed? The os-prober udeb depends on grub-mount-udeb (on the architectures where fuse is available), but os-prober doesn't depend on grub-common (the package shipping grub-mount). There isn't even a recommends or suggests. When grub-mount fails, os-prober sets the device read-only and tries to mount it. It looks like the error reported in this bug was caused by setting the device read-only, not by mounting it. The mount didn't change anything, because the device was read-only. The mount probably would have changed the filesystem (by replaying the journal) if the device was not read-only. A fix for this could be to create a read-only linear device with device-mapper and mounting that, instead of setting the device read-only. That way, the device itself doesn't have to be changed. This can only work if device mapper is available. Obviously, it seems hard to do these kinds of changes this late in the wheezy release cycle. Cheers, Ivo -- To UNSUBSCRIBE, email to debian-boot-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20130324122953.ga16...@ugent.be
