diff mbox series

[03/15] KVM: SVM: Invert the polarity of the "shadow" MSR interception bitmaps

Message ID 20241127201929.4005605-4-aaronlewis@google.com (mailing list archive)
State New
Headers show
Series Unify MSR intercepts in x86 | expand

Commit Message

Aaron Lewis Nov. 27, 2024, 8:19 p.m. UTC 
Note, a "FIXME" tag was added to svm_msr_filter_changed().  This will
be addressed later in the series after the VMX style MSR intercepts
are added to SVM.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Co-developed-by: Aaron Lewis <aaronlewis@google.com>
---
 arch/x86/kvm/svm/svm.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

Comments

Sean Christopherson Nov. 27, 2024, 8:42 p.m. UTC | #1 
On Wed, Nov 27, 2024, Aaron Lewis wrote:

I'll write a changelog for this too.

> Note, a "FIXME" tag was added to svm_msr_filter_changed().  This will

Write changelogs in imperative mood, i.e. state what the patch is doing as a
command.  Don't describe what will have happened after the patch is applied.
Using imperative mood allows for using indicative mood to describe what was
already there, and/or what happened in the past.

> be addressed later in the series after the VMX style MSR intercepts
> are added to SVM.
> 
> Signed-off-by: Sean Christopherson <seanjc@google.com>
> Co-developed-by: Aaron Lewis <aaronlewis@google.com>

Your SoB is needed here too.  See "When to use Acked-by:, Cc:, and Co-developed-by:"
in Documentation/process/submitting-patches.rst.
diff mbox series

Patch

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 7433dd2a32925..f534cdbba0585 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -781,14 +781,14 @@  static void set_shadow_msr_intercept(struct kvm_vcpu *vcpu, u32 msr, int read,
 
 	/* Set the shadow bitmaps to the desired intercept states */
 	if (read)
-		__set_bit(slot, svm->shadow_msr_intercept.read);
-	else
 		__clear_bit(slot, svm->shadow_msr_intercept.read);
+	else
+		__set_bit(slot, svm->shadow_msr_intercept.read);
 
 	if (write)
-		__set_bit(slot, svm->shadow_msr_intercept.write);
-	else
 		__clear_bit(slot, svm->shadow_msr_intercept.write);
+	else
+		__set_bit(slot, svm->shadow_msr_intercept.write);
 }
 
 static bool valid_msr_intercept(u32 index)
@@ -934,9 +934,10 @@  static void svm_msr_filter_changed(struct kvm_vcpu *vcpu)
 	 */
 	for (i = 0; direct_access_msrs[i].index != MSR_INVALID; i++) {
 		u32 msr = direct_access_msrs[i].index;
-		u32 read = test_bit(i, svm->shadow_msr_intercept.read);
-		u32 write = test_bit(i, svm->shadow_msr_intercept.write);
+		u32 read = !test_bit(i, svm->shadow_msr_intercept.read);
+		u32 write = !test_bit(i, svm->shadow_msr_intercept.write);
 
+		/* FIXME: Align the polarity of the bitmaps and params. */
 		set_msr_interception_bitmap(vcpu, svm->msrpm, msr, read, write);
 	}
 }
@@ -1453,6 +1454,10 @@  static int svm_vcpu_create(struct kvm_vcpu *vcpu)
 	if (err)
 		goto error_free_vmsa_page;
 
+	/* All MSRs start out in the "intercepted" state. */
+	bitmap_fill(svm->shadow_msr_intercept.read, MAX_DIRECT_ACCESS_MSRS);
+	bitmap_fill(svm->shadow_msr_intercept.write, MAX_DIRECT_ACCESS_MSRS);
+
 	svm->msrpm = svm_vcpu_alloc_msrpm();
 	if (!svm->msrpm) {
 		err = -ENOMEM;