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Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c93
1 files changed, 35 insertions, 58 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 5d4c86133453..1349e278cd2a 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -477,8 +477,11 @@ static int emulator_check_intercept(struct x86_emulate_ctxt *ctxt,
.dst_val = ctxt->dst.val64,
.src_bytes = ctxt->src.bytes,
.dst_bytes = ctxt->dst.bytes,
+ .src_type = ctxt->src.type,
+ .dst_type = ctxt->dst.type,
.ad_bytes = ctxt->ad_bytes,
- .next_rip = ctxt->eip,
+ .rip = ctxt->eip,
+ .next_rip = ctxt->_eip,
};
return ctxt->ops->intercept(ctxt, &info, stage);
@@ -651,9 +654,10 @@ 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 !__is_canonical_address(la, ctxt_virt_addr_bits(ctxt));
+ return !ctxt->ops->is_canonical_addr(ctxt, la, flags);
}
/*
@@ -1069,7 +1073,7 @@ static __always_inline u8 test_cc(unsigned int condition, unsigned long flags)
flags = (flags & EFLAGS_MASK) | X86_EFLAGS_IF;
asm("push %[flags]; popf; " CALL_NOSPEC
- : "=a"(rc) : [thunk_target]"r"(fop), [flags]"r"(flags));
+ : "=a"(rc), ASM_CALL_CONSTRAINT : [thunk_target]"r"(fop), [flags]"r"(flags));
return rc;
}
@@ -1733,7 +1737,8 @@ 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);
}
@@ -2354,50 +2359,6 @@ setup_syscalls_segments(struct desc_struct *cs, struct desc_struct *ss)
ss->avl = 0;
}
-static bool vendor_intel(struct x86_emulate_ctxt *ctxt)
-{
- u32 eax, ebx, ecx, edx;
-
- eax = ecx = 0;
- ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
- return is_guest_vendor_intel(ebx, ecx, edx);
-}
-
-static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt)
-{
- const struct x86_emulate_ops *ops = ctxt->ops;
- u32 eax, ebx, ecx, edx;
-
- /*
- * syscall should always be enabled in longmode - so only become
- * vendor specific (cpuid) if other modes are active...
- */
- if (ctxt->mode == X86EMUL_MODE_PROT64)
- return true;
-
- eax = 0x00000000;
- ecx = 0x00000000;
- ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
- /*
- * remark: Intel CPUs only support "syscall" in 64bit longmode. Also a
- * 64bit guest with a 32bit compat-app running will #UD !! While this
- * behaviour can be fixed (by emulating) into AMD response - CPUs of
- * AMD can't behave like Intel.
- */
- if (is_guest_vendor_intel(ebx, ecx, edx))
- return false;
-
- if (is_guest_vendor_amd(ebx, ecx, edx) ||
- is_guest_vendor_hygon(ebx, ecx, edx))
- return true;
-
- /*
- * default: (not Intel, not AMD, not Hygon), apply Intel's
- * stricter rules...
- */
- return false;
-}
-
static int em_syscall(struct x86_emulate_ctxt *ctxt)
{
const struct x86_emulate_ops *ops = ctxt->ops;
@@ -2411,7 +2372,15 @@ static int em_syscall(struct x86_emulate_ctxt *ctxt)
ctxt->mode == X86EMUL_MODE_VM86)
return emulate_ud(ctxt);
- if (!(em_syscall_is_enabled(ctxt)))
+ /*
+ * Intel compatible CPUs only support SYSCALL in 64-bit mode, whereas
+ * AMD allows SYSCALL in any flavor of protected mode. Note, it's
+ * infeasible to emulate Intel behavior when running on AMD hardware,
+ * as SYSCALL won't fault in the "wrong" mode, i.e. there is no #UD
+ * for KVM to trap-and-emulate, unlike emulating AMD on Intel.
+ */
+ if (ctxt->mode != X86EMUL_MODE_PROT64 &&
+ ctxt->ops->guest_cpuid_is_intel_compatible(ctxt))
return emulate_ud(ctxt);
ops->get_msr(ctxt, MSR_EFER, &efer);
@@ -2471,11 +2440,11 @@ static int em_sysenter(struct x86_emulate_ctxt *ctxt)
return emulate_gp(ctxt, 0);
/*
- * Not recognized on AMD in compat mode (but is recognized in legacy
- * mode).
+ * Intel's architecture allows SYSENTER in compatibility mode, but AMD
+ * does not. Note, AMD does allow SYSENTER in legacy protected mode.
*/
- if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA)
- && !vendor_intel(ctxt))
+ if ((ctxt->mode != X86EMUL_MODE_PROT64) && (efer & EFER_LMA) &&
+ !ctxt->ops->guest_cpuid_is_intel_compatible(ctxt))
return emulate_ud(ctxt);
/* sysenter/sysexit have not been tested in 64bit mode. */
@@ -2552,8 +2521,8 @@ 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;
}
@@ -2647,7 +2616,14 @@ static void string_registers_quirk(struct x86_emulate_ctxt *ctxt)
* manner when ECX is zero due to REP-string optimizations.
*/
#ifdef CONFIG_X86_64
- if (ctxt->ad_bytes != 4 || !vendor_intel(ctxt))
+ u32 eax, ebx, ecx, edx;
+
+ if (ctxt->ad_bytes != 4)
+ return;
+
+ eax = ecx = 0;
+ ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, true);
+ if (!is_guest_vendor_intel(ebx, ecx, edx))
return;
*reg_write(ctxt, VCPU_REGS_RCX) = 0;
@@ -3523,7 +3499,8 @@ 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);