hv: fix using cpuid does not clear the upper 32-bit registers.

In HV, cpuid uses the lower 32 bits of rax\rbx\rcx\rdx registers to pass parameters, But the software does not clear the upper 32-bit registers, if the guest uses 64-bit variables to pass parameters to cpuid，guest will use rax\rbx\rcx\rdx, not eax\ebx\ecx\edx, the previous value of the high 32 registers will affect the guest. Tracked-On: projectacrn#8605 Reviewed-by: Junjie Mao <[email protected]> Signed-off-by: andi6 <[email protected]>
476997779 · May 29, 2024 · 2aace19 · 2aace19
1 parent b885d02
commit 2aace19
Showing 1 changed file with 12 additions and 13 deletions.
diff --git a/hypervisor/arch/x86/guest/vmexit.c b/hypervisor/arch/x86/guest/vmexit.c
@@ -354,19 +354,18 @@ static int32_t hlt_vmexit_handler(struct acrn_vcpu *vcpu)
 
 int32_t cpuid_vmexit_handler(struct acrn_vcpu *vcpu)
 {
-	uint64_t rax, rbx, rcx, rdx;
-
-	rax = vcpu_get_gpreg(vcpu, CPU_REG_RAX);
-	rbx = vcpu_get_gpreg(vcpu, CPU_REG_RBX);
-	rcx = vcpu_get_gpreg(vcpu, CPU_REG_RCX);
-	rdx = vcpu_get_gpreg(vcpu, CPU_REG_RDX);
-	TRACE_2L(TRACE_VMEXIT_CPUID, rax, rcx);
-	guest_cpuid(vcpu, (uint32_t *)&rax, (uint32_t *)&rbx,
-		(uint32_t *)&rcx, (uint32_t *)&rdx);
-	vcpu_set_gpreg(vcpu, CPU_REG_RAX, rax);
-	vcpu_set_gpreg(vcpu, CPU_REG_RBX, rbx);
-	vcpu_set_gpreg(vcpu, CPU_REG_RCX, rcx);
-	vcpu_set_gpreg(vcpu, CPU_REG_RDX, rdx);
+	uint32_t eax, ebx, ecx, edx;
+
+	eax = (uint32_t)vcpu_get_gpreg(vcpu, CPU_REG_RAX);
+	ebx = (uint32_t)vcpu_get_gpreg(vcpu, CPU_REG_RBX);
+	ecx = (uint32_t)vcpu_get_gpreg(vcpu, CPU_REG_RCX);
+	edx = (uint32_t)vcpu_get_gpreg(vcpu, CPU_REG_RDX);
+	TRACE_2L(TRACE_VMEXIT_CPUID, (uint64_t)eax, (uint64_t)ecx);
+	guest_cpuid(vcpu, &eax, &ebx, &ecx, &edx);
+	vcpu_set_gpreg(vcpu, CPU_REG_RAX, (uint64_t)eax);
+	vcpu_set_gpreg(vcpu, CPU_REG_RBX, (uint64_t)ebx);
+	vcpu_set_gpreg(vcpu, CPU_REG_RCX, (uint64_t)ecx);
+	vcpu_set_gpreg(vcpu, CPU_REG_RDX, (uint64_t)edx);
 
 	return 0;
 }