redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

KVM: x86: block guest protection keys unless the host has them enabled 

If the host has protection keys disabled, we cannot read and write the
guest PKRU---RDPKRU and WRPKRU fail with #GP(0) if CR4.PKE=0.  Block
the PKU cpuid bit in that case.

This ensures that guest_CR4.PKE=1 implies host_CR4.PKE=1.

Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
hifive-unleashed-5.1
Paolo Bonzini 2017-08-24 11:59:31 +02:00
parent bb9b52bd51
commit c469268cd5
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kvm/cpuid.c
View File

@ -469,7 +469,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
entry->ecx &= kvm_cpuid_7_0_ecx_x86_features;
cpuid_mask(&entry->ecx, CPUID_7_ECX);
/* PKU is not yet implemented for shadow paging. */
if (!tdp_enabled)
if (!tdp_enabled || !boot_cpu_has(X86_FEATURE_OSPKE))
entry->ecx &= ~F(PKU);
entry->edx &= kvm_cpuid_7_0_edx_x86_features;
entry->edx &= get_scattered_cpuid_leaf(7, 0, CPUID_EDX);