Just ran into a bug with all the HVMs I have running under Xen with a 64 bit AMD host (FC6).
Apparently the int3 debugger trap instruction gets the wrong PC reported in the VMs, so it is a pain in the patoot to do debugger development on Xen guests :-).
(Search google for "hvm int3 amd" and you can find references to patches that are fairly recent - a lot more recent than the version of Xen provided with FC6).
Any planned bugfixes in the pipe for Xen on FC6, or should I look at swapping in some completely different host?
On Tue, Jun 26, 2007 at 01:04:56PM -0400, Tom Horsley wrote:
Just ran into a bug with all the HVMs I have running under Xen with a 64 bit AMD host (FC6).
Apparently the int3 debugger trap instruction gets the wrong PC reported in the VMs, so it is a pain in the patoot to do debugger development on Xen guests :-).
(Search google for "hvm int3 amd" and you can find references to patches that are fairly recent - a lot more recent than the version of Xen provided with FC6).
Any planned bugfixes in the pipe for Xen on FC6, or should I look at swapping in some completely different host?
FC6 is basically going to stay on Xen 3.0.3, because upstream Xen totally fails to provide a stable ABI between the hypervisor & userspace tools so upgrades during course of a Fedora release will be very painful. For an example, consider if for every kernel upgrade you did, you needed to upgrade your glibc, and the new glibc wasn't compatible with your old kernel. Well that's the situation we're in with Xen & it utterly sucks. So FC6 will stay on Xen 3.0.3. If you have HVM issues the best bet is to switch to Fedora 7 whcih is baed on Xen 3.1.0 which has much more advanced HVM support.
Regards, Dan.
On Wed, 27 Jun 2007 14:35:32 +0100 "Daniel P. Berrange" berrange@redhat.com wrote:
So FC6 will stay on Xen 3.0.3. If you have HVM issues the best bet is to switch to Fedora 7 whcih is baed on Xen 3.1.0 which has much more advanced HVM support.
Well, I just tried installing SLES10 sp1 on the host today (xen 3.0.4 and whatever novell patches have been crammed in with it :-), and it seems to have solved my HVM problem, so I guess I'll use if for now.
I was astounded when I simply copied the VM config files from the old FC6 partition to the new sles partition and the VMs just booted with no alterations to the configs. That is so contrary to the normal linux experience :-).
xen@lists.stg.fedoraproject.org
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Daniel P. Berrange -
Tom Horsley