Bug#627587: grub-pc: grub-probe: error: cannot stat `/dev/root'.

[Adrian Bunk]

On Sat, May 28, 2011 at 11:33:37AM +0100, Colin Watson wrote:
> tag 627587 pending
> thanks
> 
> On Fri, May 27, 2011 at 11:09:21PM +0300, Adrian Bunk wrote:
> > On Sun, May 22, 2011 at 11:19:06AM +0100, Colin Watson wrote:
> > > On Sun, May 22, 2011 at 01:02:01PM +0300, Adrian Bunk wrote:
> > > > grub-probe: error: cannot stat `/dev/root'.
> > > 
> > > Looks like #621738, which only affects people without initrds
> > 
> > Matched my setup.
> > 
> > > (I'm not sure if that's a sufficient condition, but I gather it's a
> > > necessary condition).  Do you have the most recent udev package
> > > installed?
> > 
> > I did not, and it works after an udev upgrade.
> > 
> > It seems that has to be expressed through a Conflicts on older udev 
> > versions?
> 
> (That should be Breaks, nowadays.)

I'm not sure what exactly is correct here since udev at least has to be 
configured before grub.

> I'm not sure how effective that will be.  After all, the bug only
> affects users of systemd,

I don't have systemd installed.

> by the looks of that other bug, and popcon
> only shows systemd being used by at most 0.2% of the users of grub2, and
> even then it's only the subset without initrds who are affected.  The
> rest have no need to upgrade.  Plus, it's not clear to me from that
> other bug report whether you need to reboot with the new udev or
> otherwise manually restart udev before the fix is effective,

My guess is that the restart of udev in it's postinst is enough,
but that is just a guess.

> and if so
> then a Conflicts/Breaks would be insufficient anyway; and, by the time
> grub2 packages with such a change reach testing, a fixed udev might well
> already be there.

That won't help people upgrading from squeeze.

> Still, I suppose I can give it a go (at least on non-Ubuntu-derived
> systems; Ubuntu's udev doesn't share history with Debian's).  At the
> very least, it might serve as some kind of documentation.
> 
> Cheers,

cu
Adrian

-- 

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