From 9d88fca71a99a65c37cbfe481b4aa4e91a27ff13 Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Sun, 2 Nov 2014 11:54:52 +0200 Subject: [PATCH] KVM: x86: MOV to CR3 can set bit 63 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Although Intel SDM mentions bit 63 is reserved, MOV to CR3 can have bit 63 set. As Intel SDM states in section 4.10.4 "Invalidation of TLBs and Paging-Structure Caches": " MOV to CR3. ... If CR4.PCIDE = 1 and bit 63 of the instruction’s source operand is 0 ..." In other words, bit 63 is not reserved. KVM emulator currently consider bit 63 as reserved. Fix it. Signed-off-by: Nadav Amit Signed-off-by: Paolo Bonzini --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/emulate.c | 2 +- arch/x86/kvm/x86.c | 2 ++ 3 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 904535fe825e..dc932d388c43 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -51,6 +51,7 @@ | X86_CR0_NW | X86_CR0_CD | X86_CR0_PG)) #define CR3_L_MODE_RESERVED_BITS 0xFFFFFF0000000000ULL +#define CR3_PCID_INVD (1UL << 63) #define CR4_RESERVED_BITS \ (~(unsigned long)(X86_CR4_VME | X86_CR4_PVI | X86_CR4_TSD | X86_CR4_DE\ | X86_CR4_PSE | X86_CR4_PAE | X86_CR4_MCE \ diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a2a9c18b42e4..9f960b428bb2 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3564,7 +3564,7 @@ static int check_cr_write(struct x86_emulate_ctxt *ctxt) ctxt->ops->get_msr(ctxt, MSR_EFER, &efer); if (efer & EFER_LMA) - rsvd = CR3_L_MODE_RESERVED_BITS; + rsvd = CR3_L_MODE_RESERVED_BITS & ~CR3_PCID_INVD; if (new_val & rsvd) return emulate_gp(ctxt, 0); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 773c17ec42dd..641358865a0c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -750,6 +750,8 @@ EXPORT_SYMBOL_GPL(kvm_set_cr4); int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) { + cr3 &= ~CR3_PCID_INVD; + if (cr3 == kvm_read_cr3(vcpu) && !pdptrs_changed(vcpu)) { kvm_mmu_sync_roots(vcpu); kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu); -- 2.34.1