From 346874c9507a2582d0c00021f848de6e115f276c Mon Sep 17 00:00:00 2001 From: Nadav Amit Date: Fri, 18 Apr 2014 03:35:09 +0300 Subject: [PATCH] KVM: x86: Fix CR3 reserved bits According to Intel specifications, PAE and non-PAE does not have any reserved bits. In long-mode, regardless to PCIDE, only the high bits (above the physical address) are reserved. Signed-off-by: Nadav Amit Signed-off-by: Marcelo Tosatti --- arch/x86/include/asm/kvm_host.h | 6 +----- arch/x86/kvm/emulate.c | 4 ---- arch/x86/kvm/x86.c | 25 +++++-------------------- 3 files changed, 6 insertions(+), 29 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 7de069afb38..e21aee98a5c 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -50,11 +50,7 @@ | X86_CR0_ET | X86_CR0_NE | X86_CR0_WP | X86_CR0_AM \ | X86_CR0_NW | X86_CR0_CD | X86_CR0_PG)) -#define CR3_PAE_RESERVED_BITS ((X86_CR3_PWT | X86_CR3_PCD) - 1) -#define CR3_NONPAE_RESERVED_BITS ((PAGE_SIZE-1) & ~(X86_CR3_PWT | X86_CR3_PCD)) -#define CR3_PCID_ENABLED_RESERVED_BITS 0xFFFFFF0000000000ULL -#define CR3_L_MODE_RESERVED_BITS (CR3_NONPAE_RESERVED_BITS | \ - 0xFFFFFF0000000000ULL) +#define CR3_L_MODE_RESERVED_BITS 0xFFFFFF0000000000ULL #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 0dec502d20b..f3834bbca1d 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -3388,10 +3388,6 @@ 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; - else if (ctxt->ops->get_cr(ctxt, 4) & X86_CR4_PAE) - rsvd = CR3_PAE_RESERVED_BITS; - else if (ctxt->ops->get_cr(ctxt, 0) & X86_CR0_PG) - rsvd = CR3_NONPAE_RESERVED_BITS; if (new_val & rsvd) return emulate_gp(ctxt, 0); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index bc4aaf68190..e4ccc6cf410 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -701,26 +701,11 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) return 0; } - if (is_long_mode(vcpu)) { - if (kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE)) { - if (cr3 & CR3_PCID_ENABLED_RESERVED_BITS) - return 1; - } else - if (cr3 & CR3_L_MODE_RESERVED_BITS) - return 1; - } else { - if (is_pae(vcpu)) { - if (cr3 & CR3_PAE_RESERVED_BITS) - return 1; - if (is_paging(vcpu) && - !load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)) - return 1; - } - /* - * We don't check reserved bits in nonpae mode, because - * this isn't enforced, and VMware depends on this. - */ - } + if (is_long_mode(vcpu) && (cr3 & CR3_L_MODE_RESERVED_BITS)) + return 1; + if (is_pae(vcpu) && is_paging(vcpu) && + !load_pdptrs(vcpu, vcpu->arch.walk_mmu, cr3)) + return 1; vcpu->arch.cr3 = cr3; __set_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail); -- 2.46.0