Jan Beulich
2006-Nov-22 08:36 UTC
[Xen-devel] PAE requirement in config file for HVM guests
Could anyone explain why it was necessary in 3.0.3 to require config files for 32-bit/PAE or 64-bit x86 hvm guests on respective hypervisors to have an explicit ''pae = 1'', whereas in 3.0.2 this wasn''t needed? It would seem that the emulated CPUID feature flag should, as in 3.0.2, just be suppressed if the hypervisor really can''t support PAE (i.e. 32-bit non-PAE build). Thanks, Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Keir Fraser
2006-Nov-22 09:47 UTC
Re: [Xen-devel] PAE requirement in config file for HVM guests
On 22/11/06 08:36, "Jan Beulich" <jbeulich@novell.com> wrote:> Could anyone explain why it was necessary in 3.0.3 to require config files > for 32-bit/PAE or 64-bit x86 hvm guests on respective hypervisors to have > an explicit ''pae = 1'', whereas in 3.0.2 this wasn''t needed? It would seem > that the emulated CPUID feature flag should, as in 3.0.2, just be > suppressed if the hypervisor really can''t support PAE (i.e. 32-bit non-PAE > build).It''s only to allow pae to be masked off. I think that you can specify pae=1 always and it won''t be advertised to the guest if the host doesn''t support it. If this isn''t the case it should be, and I''d take a patch to make it so. :-) Oh, and xend should default pae=1 if it doesn''t do so already. -- Keir _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel