Re: Fix for NetBSD Dom0 boot problem

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

Manuel, 

you may update pkgsrc another time :)

This time there's an official fix for your xenkernel3/patches/patch-ba, rev 
1.2.

According to the commit message it fixes a real boot problem and
another "boot problem" :)

The real boot problem is related when NetBSD Dom0 tries to allocate
DMA-safe memory above 4GB RAM.
The other "boot problem" is the memory truncation to 166GB if you 
have more than that.

The diff is this:
http://xenbits.xensource.com/staging/xen-unstable.hg/rev/cd5e1e76d0bc

To get the diff, use your repository you already fetched and run:
hg pull -u
hg diff -p -r16547 -r16548 >netbsd_dom0_bootfix.diff

Christoph



On Thursday 06 December 2007 09:08:17 Christoph Egger wrote:
> On Wednesday 05 December 2007 23:11:31 Manuel Bouyer wrote:
> > On Wed, Dec 05, 2007 at 06:23:46PM +0100, Christoph Egger wrote:
> > > Hi Manuel,
> > >
> > > Please update pkgsrc's xenkernel3/patches/patch-ba:
> > >
> > > hg clone http://xenbits.xensource.com/staging/xen-unstable.hg/
> > > hg diff -p -r16534 -r16535 >netbsd_dom0_bootfix.diff
> > >
> > > The content of netbsd_dom0_bootfix.diff should match this:
> > > http://xenbits.xensource.com/staging/xen-unstable.hg/rev/c67d024fdd2d
> > >
> > > Add this diff to above patch-ba.
> > >
> > >
> > > This fixes a NetBSD Dom0 Xen-amd64 boot problem for me, which I have
> > > with Xen 3.1.x and Xen-unstable. The Xen crash output is below. The
> > > crash happened right before NetBSD loaded the symbol table.
> > >
> > > The bug was a trampoline mapping leaking into Dom0s address space.
> > > And the bug was hit when the Dom0 freed the pagetable.
> > >
> > > Linux Dom0 uses the builder-provided pagetable as its kernel idle
> > > pagetable. So it never frees the pagetable and so never hit the bad
> > > path.
> > >
> > > Oh, I have no idea how you got NetBSD Dom0 booting without that fix.
> >
> > Yes, I did it see that problem too. It crashes when it tries to unpin the
> > L4 page table provided by Xen. I debugged it and came with patch-cy in
> > xenkernel3. I now have commited the Xen offical fix, and removed patch-cy
> > which should have never been there in the first place (the same file
> > patched twice ...) Thanks !
>
> You're welcome.
>
> Oh, I see you updated pkgsrc to Xen 3.1.2. There will also be a Xen 3.1.3.
> But I don't know what comes first: 3.1.3 or 3.2.0.
> Anyway, whenever 3.2.0 is out, I highly recommend you to package that one,
> since this is of much more value for *BSD.
>
> Now that you fetched xen-unstable in order to get the diff for patch-ba,
> you can give it a try and give me feedback. :-)
> Just run 'gmake' on the top-level directory and enjoy the result.
>
> Apply attached patch to make tools/blktap building, but not functional
> on *BSD. I don't submit this one since it has not the quality, but it's a
> start. Applying this on Xen 3.1.2 makes tools/blktap NOT building because
> I already got two patches upstream which remove linux specific dependencies
> in other files (i.e. #include <linux/fs.h> without actually using it.)
>
> > BTW, I posted this to xen-devel@, but it seems it never went to the list
> > (I can't see it in the archives), and got no bounce either. Do you know
> > if this list is restricted in some way ?
>
> I am subscribed there but never saw your mail. I am not aware of any
> restrictions.
>
> Christoph