Re: [PATCH v5 00/15] KVM: SVM: Misc SEV cleanups

[Sean Christopherson]

On Thu, Apr 22, 2021, Paolo Bonzini wrote:
> > Paolo Bonzini (1):
> >    KVM: SEV: Mask CPUID[0x8000001F].eax according to supported features
> > 
> > Sean Christopherson (14):
> >    KVM: SVM: Zero out the VMCB array used to track SEV ASID association
> >    KVM: SVM: Free sev_asid_bitmap during init if SEV setup fails
> >    KVM: SVM: Disable SEV/SEV-ES if NPT is disabled
> >    KVM: SVM: Move SEV module params/variables to sev.c
> >    x86/sev: Drop redundant and potentially misleading 'sev_enabled'
> >    KVM: SVM: Append "_enabled" to module-scoped SEV/SEV-ES control
> >      variables
> >    KVM: SVM: Condition sev_enabled and sev_es_enabled on
> >      CONFIG_KVM_AMD_SEV=y
> >    KVM: SVM: Enable SEV/SEV-ES functionality by default (when supported)
> >    KVM: SVM: Unconditionally invoke sev_hardware_teardown()
> >    KVM: SVM: Explicitly check max SEV ASID during sev_hardware_setup()
> >    KVM: SVM: Move SEV VMCB tracking allocation to sev.c
> >    KVM: SVM: Drop redundant svm_sev_enabled() helper
> >    KVM: SVM: Remove an unnecessary prototype declaration of
> >      sev_flush_asids()
> >    KVM: SVM: Skip SEV cache flush if no ASIDs have been used
> > 
> >   arch/x86/include/asm/mem_encrypt.h |  1 -
> >   arch/x86/kvm/cpuid.c               |  8 ++-
> >   arch/x86/kvm/cpuid.h               |  1 +
> >   arch/x86/kvm/svm/sev.c             | 80 ++++++++++++++++++++++--------
> >   arch/x86/kvm/svm/svm.c             | 57 +++++++++------------
> >   arch/x86/kvm/svm/svm.h             |  9 +---
> >   arch/x86/mm/mem_encrypt.c          | 12 ++---
> >   arch/x86/mm/mem_encrypt_identity.c |  1 -
> >   8 files changed, 97 insertions(+), 72 deletions(-)
> > 
> 
> Queued except for patch 6, send that separately since it's purely x86 and
> maintainers will likely not notice it inside this thread.  You probably want
> to avoid conflicts by waiting for the migration patches, though.

It can't be sent separately, having both the kernel's sev_enabled and KVM's
sev_enabled doesn't build with CONFIG_AMD_MEM_ENCRYPT=y:

arch/x86/kvm/svm/sev.c:33:13: error: static declaration of ‘sev_enabled’ follows non-static declaration
   33 | static bool sev_enabled = true;
      |             ^~~~~~~~~~~
In file included from include/linux/mem_encrypt.h:17,
                 from arch/x86/include/asm/page_types.h:7,
                 from arch/x86/include/asm/page.h:9,
                 from arch/x86/include/asm/thread_info.h:12,
                 from include/linux/thread_info.h:58,
                 from arch/x86/include/asm/preempt.h:7,
                 from include/linux/preempt.h:78,
                 from include/linux/percpu.h:6,
                 from include/linux/context_tracking_state.h:5,
                 from include/linux/hardirq.h:5,
                 from include/linux/kvm_host.h:7,
                 from arch/x86/kvm/svm/sev.c:11:
arch/x86/include/asm/mem_encrypt.h:23:13: note: previous declaration of ‘sev_enabled’ was here
   23 | extern bool sev_enabled;
      |             ^~~~~~~~~~~
make[3]: *** [scripts/Makefile.build:271: arch/x86/kvm/svm/sev.o] Error 1