Christoph Egger
2010-Aug-05 15:02 UTC
[Xen-devel] [PATCH 06/14] Nested Virtualization: CRn & paged real mode
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com> -- ---to satisfy European Law for business letters: Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Tim Deegan
2010-Aug-09 12:40 UTC
Re: [Xen-devel] [PATCH 06/14] Nested Virtualization: CRn & paged real mode
> Allow paged real mode during vmrun emulation. > Emulate cr0 and cr4 when guest does not intercept them.I understand the paged-real-mode case, but why do you also allow CR0.CD and CR0.NW for nested VMs? Cheers, Tim.> diff -r 917f9eb07fc3 -r b1a356e5658d xen/arch/x86/hvm/hvm.c > --- a/xen/arch/x86/hvm/hvm.c > +++ b/xen/arch/x86/hvm/hvm.c > @@ -54,6 +54,7 @@ > #include <asm/hvm/support.h> > #include <asm/hvm/cacheattr.h> > #include <asm/hvm/trace.h> > +#include <asm/hvm/nestedhvm.h> > #include <asm/mtrr.h> > #include <asm/apic.h> > #include <public/sched.h> > @@ -1105,7 +1106,8 @@ int hvm_set_cr0(unsigned long value) > /* ET is reserved and should be always be 1. */ > value |= X86_CR0_ET; > > - if ( (value & (X86_CR0_PE | X86_CR0_PG)) == X86_CR0_PG ) > + if ( !nestedhvm_vmentry_emulate(v) && > + (value & (X86_CR0_PE | X86_CR0_PG)) == X86_CR0_PG ) > goto gpf; > > if ( (value & X86_CR0_PG) && !(old_value & X86_CR0_PG) ) > @@ -1159,7 +1161,7 @@ int hvm_set_cr0(unsigned long value) > } > } > > - if ( has_arch_mmios(v->domain) ) > + if ( !nestedhvm_vmentry_emulate(v) && has_arch_mmios(v->domain) ) > { > if ( (value & X86_CR0_CD) && !(value & X86_CR0_NW) ) > {Content-Description: ATT00001..txt> _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel-- Tim Deegan <Tim.Deegan@citrix.com> Principal Software Engineer, XenServer Engineering Citrix Systems UK Ltd. (Company #02937203, SL9 0BG) _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Christoph Egger
2010-Aug-11 09:12 UTC
Re: [Xen-devel] [PATCH 06/14] Nested Virtualization: CRn & paged real mode
On Monday 09 August 2010 14:40:12 Tim Deegan wrote:> > Allow paged real mode during vmrun emulation. > > Emulate cr0 and cr4 when guest does not intercept them. > > I understand the paged-real-mode case, but why do you also allow CR0.CD > and CR0.NW for nested VMs?Oh, I haven''t considered about those bits. You are right, they should not be allowed for l2 guests. Thanks for bringing this up. Fixed in my local tree. Christoph> > Cheers, > > Tim. > > > diff -r 917f9eb07fc3 -r b1a356e5658d xen/arch/x86/hvm/hvm.c > > --- a/xen/arch/x86/hvm/hvm.c > > +++ b/xen/arch/x86/hvm/hvm.c > > @@ -54,6 +54,7 @@ > > #include <asm/hvm/support.h> > > #include <asm/hvm/cacheattr.h> > > #include <asm/hvm/trace.h> > > +#include <asm/hvm/nestedhvm.h> > > #include <asm/mtrr.h> > > #include <asm/apic.h> > > #include <public/sched.h> > > @@ -1105,7 +1106,8 @@ int hvm_set_cr0(unsigned long value) > > /* ET is reserved and should be always be 1. */ > > value |= X86_CR0_ET; > > > > - if ( (value & (X86_CR0_PE | X86_CR0_PG)) == X86_CR0_PG ) > > + if ( !nestedhvm_vmentry_emulate(v) && > > + (value & (X86_CR0_PE | X86_CR0_PG)) == X86_CR0_PG ) > > goto gpf; > > > > if ( (value & X86_CR0_PG) && !(old_value & X86_CR0_PG) ) > > @@ -1159,7 +1161,7 @@ int hvm_set_cr0(unsigned long value) > > } > > } > > > > - if ( has_arch_mmios(v->domain) ) > > + if ( !nestedhvm_vmentry_emulate(v) && has_arch_mmios(v->domain) ) > > { > > if ( (value & X86_CR0_CD) && !(value & X86_CR0_NW) ) > > { > > Content-Description: ATT00001..txt > > > _______________________________________________ > > Xen-devel mailing list > > Xen-devel@lists.xensource.com > > http://lists.xensource.com/xen-devel-- ---to satisfy European Law for business letters: Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach b. Muenchen Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen Registergericht Muenchen, HRB Nr. 43632 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel