[PATCH v2 8/9] KVM: vmx: handle_cr ignores 32/64-bit mode
On 32-bit mode only bits [31:0] of the CR should be used for setting the CR
value. Otherwise, the host may incorrectly assume the value is invalid if bits
[63:32] are not zero. Moreover, the CR is currently being read twice when CR8
is used. Last, nested mov-cr exiting is modified to handle the CR value
correctly as well.
Signed-off-by: Nadav Amit
---
arch/x86/kvm/vmx.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index c0f53a0..cbfbb8b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5039,7 +5039,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
reg = (exit_qualification >> 8) & 15;
switch ((exit_qualification >> 4) & 3) {
case 0: /* mov to cr */
- val = kvm_register_read(vcpu, reg);
+ val = kvm_register_readl(vcpu, reg);
trace_kvm_cr_write(cr, val);
switch (cr) {
case 0:
@@ -5056,7 +5056,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
return 1;
case 8: {
u8 cr8_prev = kvm_get_cr8(vcpu);
- u8 cr8 = kvm_register_read(vcpu, reg);
+ u8 cr8 = (u8)val;
err = kvm_set_cr8(vcpu, cr8);
kvm_complete_insn_gp(vcpu, err);
if (irqchip_in_kernel(vcpu->kvm))
@@ -6751,7 +6751,7 @@ static bool nested_vmx_exit_handled_cr(struct kvm_vcpu
*vcpu,
unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
int cr = exit_qualification & 15;
int reg = (exit_qualification >> 8) & 15;
- unsigned long val = kvm_register_read(vcpu, reg);
+ unsigned long val = kvm_register_readl(vcpu, reg);
switch ((exit_qualification >> 4) & 3) {
case 0: /* mov to cr */
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH v2 8/9] KVM: vmx: handle_cr ignores 32/64-bit mode
On 32-bit mode only bits [31:0] of the CR should be used for setting the CR
value. Otherwise, the host may incorrectly assume the value is invalid if bits
[63:32] are not zero. Moreover, the CR is currently being read twice when CR8
is used. Last, nested mov-cr exiting is modified to handle the CR value
correctly as well.
Signed-off-by: Nadav Amit na...@cs.technion.ac.il
---
arch/x86/kvm/vmx.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index c0f53a0..cbfbb8b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5039,7 +5039,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
reg = (exit_qualification 8) 15;
switch ((exit_qualification 4) 3) {
case 0: /* mov to cr */
- val = kvm_register_read(vcpu, reg);
+ val = kvm_register_readl(vcpu, reg);
trace_kvm_cr_write(cr, val);
switch (cr) {
case 0:
@@ -5056,7 +5056,7 @@ static int handle_cr(struct kvm_vcpu *vcpu)
return 1;
case 8: {
u8 cr8_prev = kvm_get_cr8(vcpu);
- u8 cr8 = kvm_register_read(vcpu, reg);
+ u8 cr8 = (u8)val;
err = kvm_set_cr8(vcpu, cr8);
kvm_complete_insn_gp(vcpu, err);
if (irqchip_in_kernel(vcpu-kvm))
@@ -6751,7 +6751,7 @@ static bool nested_vmx_exit_handled_cr(struct kvm_vcpu
*vcpu,
unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
int cr = exit_qualification 15;
int reg = (exit_qualification 8) 15;
- unsigned long val = kvm_register_read(vcpu, reg);
+ unsigned long val = kvm_register_readl(vcpu, reg);
switch ((exit_qualification 4) 3) {
case 0: /* mov to cr */
--
1.9.1
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
