From 9d8c1d1814b744d0fb41085463db5d8ae025607e Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Fri, 25 Jan 2019 16:23:46 +0000 Subject: [PATCH] x86/hvm: Fix bit checking for CR4 and MSR_EFER Before the cpuid_policy logic came along, %cr4/EFER auditing on migrate-in was complicated, because at that point no CPUID information had been set for the guest. Auditing against the host CPUID was better than nothing, but not ideal. Similarly at the time, PVHv1 lacked the "CPUID passed through from hardware" behaviour with PV guests had, and PVH dom0 had to be special-cased to be able to boot. Order of information in the migration stream is still an issue (hence we still need to keep the restore parameter to cope with a nested virt corner case for %cr4), but since Xen 4.9, all domains start with a suitable CPUID policy, which is a more appropriate upper bound than host_cpuid_policy. Finally, reposition the UMIP logic as it is the only row out of order. Signed-off-by: Andrew Cooper Reviewed-by: Jan Beulich Reviewed-by: Wei Liu Release-acked-by: Juergen Gross --- xen/arch/x86/hvm/hvm.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 401c4a9312..21944e9306 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -886,12 +886,7 @@ const char *hvm_efer_valid(const struct vcpu *v, uint64_t value, signed int cr0_pg) { const struct domain *d = v->domain; - const struct cpuid_policy *p; - - if ( cr0_pg < 0 && !is_hardware_domain(d) ) - p = d->arch.cpuid; - else - p = &host_cpuid_policy; + const struct cpuid_policy *p = d->arch.cpuid; if ( value & ~EFER_KNOWN_MASK ) return "Unknown bits set"; @@ -928,14 +923,9 @@ const char *hvm_efer_valid(const struct vcpu *v, uint64_t value, /* These bits in CR4 can be set by the guest. */ unsigned long hvm_cr4_guest_valid_bits(const struct domain *d, bool restore) { - const struct cpuid_policy *p; + const struct cpuid_policy *p = d->arch.cpuid; bool mce, vmxe; - if ( !restore && !is_hardware_domain(d) ) - p = d->arch.cpuid; - else - p = &host_cpuid_policy; - /* Logic broken out simply to aid readability below. */ mce = p->basic.mce || p->basic.mca; vmxe = p->basic.vmx && (restore || nestedhvm_enabled(d)); @@ -950,13 +940,13 @@ unsigned long hvm_cr4_guest_valid_bits(const struct domain *d, bool restore) X86_CR4_PCE | (p->basic.fxsr ? X86_CR4_OSFXSR : 0) | (p->basic.sse ? X86_CR4_OSXMMEXCPT : 0) | + (p->feat.umip ? X86_CR4_UMIP : 0) | (vmxe ? X86_CR4_VMXE : 0) | (p->feat.fsgsbase ? X86_CR4_FSGSBASE : 0) | (p->basic.pcid ? X86_CR4_PCIDE : 0) | (p->basic.xsave ? X86_CR4_OSXSAVE : 0) | (p->feat.smep ? X86_CR4_SMEP : 0) | (p->feat.smap ? X86_CR4_SMAP : 0) | - (p->feat.umip ? X86_CR4_UMIP : 0) | (p->feat.pku ? X86_CR4_PKE : 0)); } -- 2.30.2