Re: [Pkg-xen-devel] Graphics driver fixes for squeeze kernel-xen ?

[Ian Campbell <ijc@hellion.org.uk>]

On Wed, 2010-08-25 at 07:11 +0100, Ian Campbell wrote:
> On Wed, 2010-08-25 at 01:13 +0100, Ben Hutchings wrote:
> > I have had to revert the addition of pvhvm because it causes
> > an instant panic under KVM (at least in a 64-bit kernel).
> 
> Ouch, I didn't think to try that combo!
> 
> I don't suppose you managed to catch the stack anywhere? I'll try and
> repro today.

So the fix is pretty simple (and the omission pretty embarrassing) but I
guess you'd prefer me to wait until after 2.6.32-21 before I update the
patches?

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 50fbf65..37d30e4 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1220,6 +1220,9 @@ static int init_hvm_pv_info(int *major, int *minor)
        u64 pfn;
 
        base = xen_cpuid_base();
+       if (!base)
+               return -EINVAL;
+
        cpuid(base + 1, &eax, &ebx, &ecx, &edx);
 
        *major = eax >> 16;



-- 
Ian Campbell
Current Noise: I - Days Of North Winds

I'm not a level-headed person...        -- Bruce Perens