x86: VMX: MSR_IA32_VMX_MISC[30] is not MBZ

PATCH Applied Nadav Amit 2 participants 2 messages Oct 3, 2019 KVM

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Nadav Amit

author

2019-10-03 01:32 UTC #0 lore raw

PATCH 1/1 x86: VMX: MSR_IA32_VMX_MISC[30] is not MBZ

MSR_IA32_VMX_MISC[30] tells whehter "VM entry allows injection of a software interrupt, software exception, or privileged software exception with an instruction length of 0".

In other words, it is not MBZ (must be zero), so do not check that it is cleared.

Signed-off-by Nadav Amit <[email protected]>

---
 x86/vmx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

x86/vmx.c +1 -1

index d518102..647ab49 100644
@@ -1486,7 +1486,7 @@ static void test_vmx_caps(void)
 	report("MSR_IA32_VMX_MISC",
 	       (!(ctrl_cpu_rev[1].clr & CPU_URG) || val & (1ul << 5)) &&
 	       ((val >> 16) & 0x1ff) <= 256 &&
-	       (val & 0xc0007e00) == 0);
+	       (val & 0x80007e00) == 0);
 
 	for (n = 0; n < ARRAY_SIZE(vmx_ctl_msr); n++) {
 		ctrl.val = rdmsr(vmx_ctl_msr[n].index);

Signature · 1 line

2.17.1

Paolo Bonzini

maintainer Applied

2019-10-03 15:23 UTC #1 lore raw

Quoted 18 lines · Nadav Amit

MSR_IA32_VMX_MISC[30] tells whehter "VM entry allows injection of a software interrupt, software exception, or privileged software exception with an instruction length of 0".
In other words, it is not MBZ (must be zero), so do not check that it is cleared.
Signed-off-by Nadav Amit <[email protected]>
---
 x86/vmx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
x86/vmx.c +0 -0
index d518102..647ab49 100644

x86/vmx.c static void test_vmx_caps(void) · line 1492

Quoted 8 lines

x86/vmx.c +1 -1

@@ -1486,7 +1486,7 @@ static void test_vmx_caps(void)
 	report("MSR_IA32_VMX_MISC",
 	       (!(ctrl_cpu_rev[1].clr & CPU_URG) || val & (1ul << 5)) &&
 	       ((val >> 16) & 0x1ff) <= 256 &&
-	       (val & 0xc0007e00) == 0);
+	       (val & 0x80007e00) == 0);
 
 	for (n = 0; n < ARRAY_SIZE(vmx_ctl_msr); n++) {
 		ctrl.val = rdmsr(vmx_ctl_msr[n].index);

Queued, thanks.

Paolo