From 16ccadefa295af434ca296e566f078223ecd79ca Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Fri, 6 Sep 2024 18:18:22 -0400 Subject: KVM: x86: Route non-canonical checks in emulator through emulate_ops Add emulate_ops.is_canonical_addr() to perform (non-)canonical checks in the emulator, which will allow extending is_noncanonical_address() to support different flavors of canonical checks, e.g. for descriptor table bases vs. MSRs, without needing duplicate logic in the emulator. No functional change is intended. Signed-off-by: Maxim Levitsky Link: https://lore.kernel.org/r/20240906221824.491834-3-mlevitsk@redhat.com [sean: separate from additional of flags, massage changelog] Signed-off-by: Sean Christopherson --- arch/x86/kvm/emulate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kvm/emulate.c') diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index e72aed25d721..3ce83f57d267 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -653,7 +653,7 @@ static inline u8 ctxt_virt_addr_bits(struct x86_emulate_ctxt *ctxt) static inline bool emul_is_noncanonical_address(u64 la, struct x86_emulate_ctxt *ctxt) { - return !__is_canonical_address(la, ctxt_virt_addr_bits(ctxt)); + return !ctxt->ops->is_canonical_addr(ctxt, la); } /* -- cgit v1.2.3 From c534b37b7584e2abc5d487b4e017f61a61959ca9 Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Fri, 6 Sep 2024 18:18:22 -0400 Subject: KVM: x86: Add X86EMUL_F_MSR and X86EMUL_F_DT_LOAD to aid canonical checks Add emulation flags for MSR accesses and Descriptor Tables loads, and pass the new flags as appropriate to emul_is_noncanonical_address(). The flags will be used to perform the correct canonical check, as the type of access affects whether or not CR4.LA57 is consulted when determining the canonical bit. No functional change is intended. Signed-off-by: Maxim Levitsky Link: https://lore.kernel.org/r/20240906221824.491834-3-mlevitsk@redhat.com [sean: split to separate patch, massage changelog] Signed-off-by: Sean Christopherson --- arch/x86/kvm/emulate.c | 15 +++++++++------ arch/x86/kvm/kvm_emulate.h | 5 ++++- arch/x86/kvm/x86.c | 2 +- 3 files changed, 14 insertions(+), 8 deletions(-) (limited to 'arch/x86/kvm/emulate.c') diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 3ce83f57d267..60986f67c35a 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -651,9 +651,10 @@ static inline u8 ctxt_virt_addr_bits(struct x86_emulate_ctxt *ctxt) } static inline bool emul_is_noncanonical_address(u64 la, - struct x86_emulate_ctxt *ctxt) + struct x86_emulate_ctxt *ctxt, + unsigned int flags) { - return !ctxt->ops->is_canonical_addr(ctxt, la); + return !ctxt->ops->is_canonical_addr(ctxt, la, flags); } /* @@ -1733,7 +1734,8 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt, if (ret != X86EMUL_CONTINUE) return ret; if (emul_is_noncanonical_address(get_desc_base(&seg_desc) | - ((u64)base3 << 32), ctxt)) + ((u64)base3 << 32), ctxt, + X86EMUL_F_DT_LOAD)) return emulate_gp(ctxt, err_code); } @@ -2516,8 +2518,8 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt) ss_sel = cs_sel + 8; cs.d = 0; cs.l = 1; - if (emul_is_noncanonical_address(rcx, ctxt) || - emul_is_noncanonical_address(rdx, ctxt)) + if (emul_is_noncanonical_address(rcx, ctxt, 0) || + emul_is_noncanonical_address(rdx, ctxt, 0)) return emulate_gp(ctxt, 0); break; } @@ -3494,7 +3496,8 @@ static int em_lgdt_lidt(struct x86_emulate_ctxt *ctxt, bool lgdt) if (rc != X86EMUL_CONTINUE) return rc; if (ctxt->mode == X86EMUL_MODE_PROT64 && - emul_is_noncanonical_address(desc_ptr.address, ctxt)) + emul_is_noncanonical_address(desc_ptr.address, ctxt, + X86EMUL_F_DT_LOAD)) return emulate_gp(ctxt, 0); if (lgdt) ctxt->ops->set_gdt(ctxt, &desc_ptr); diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h index 1b1843ff210f..10495fffb890 100644 --- a/arch/x86/kvm/kvm_emulate.h +++ b/arch/x86/kvm/kvm_emulate.h @@ -94,6 +94,8 @@ struct x86_instruction_info { #define X86EMUL_F_FETCH BIT(1) #define X86EMUL_F_IMPLICIT BIT(2) #define X86EMUL_F_INVLPG BIT(3) +#define X86EMUL_F_MSR BIT(4) +#define X86EMUL_F_DT_LOAD BIT(5) struct x86_emulate_ops { void (*vm_bugged)(struct x86_emulate_ctxt *ctxt); @@ -236,7 +238,8 @@ struct x86_emulate_ops { gva_t (*get_untagged_addr)(struct x86_emulate_ctxt *ctxt, gva_t addr, unsigned int flags); - bool (*is_canonical_addr)(struct x86_emulate_ctxt *ctxt, gva_t addr); + bool (*is_canonical_addr)(struct x86_emulate_ctxt *ctxt, gva_t addr, + unsigned int flags); }; /* Type, address-of, and value of an instruction's operand. */ diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index cd06c1d9a1f1..a4ac80d77031 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8620,7 +8620,7 @@ static gva_t emulator_get_untagged_addr(struct x86_emulate_ctxt *ctxt, } static bool emulator_is_canonical_addr(struct x86_emulate_ctxt *ctxt, - gva_t addr) + gva_t addr, unsigned int flags) { return !is_noncanonical_address(addr, emul_to_vcpu(ctxt)); } -- cgit v1.2.3