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FAILED: patch "[PATCH] KVM: SVM: Truncate GPR value for DR and CR accesses in" failed to apply to 5.12-stable tree

PATCH [email protected] 3 participants 4 messages May 12, 2021 – Jun 8, 2021

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#0 lore raw

The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 0884335a2e653b8a045083aa1d57ce74269ac81d Mon Sep 17 00:00:00 2001
From: Sean Christopherson <[email protected]>
Date: Wed, 21 Apr 2021 19:21:22 -0700
Subject: [PATCH] KVM: SVM: Truncate GPR value for DR and CR accesses in
!64-bit mode

Drop bits 63:32 on loads/stores to/from DRs and CRs when the vCPU is not in 64-bit mode. The APM states bits 63:32 are dropped for both DRs and CRs:

In 64-bit mode, the operand size is fixed at 64 bits without the need for a REX prefix. In non-64-bit mode, the operand size is fixed at 32 bits and the upper 32 bits of the destination are forced to 0.

Fixes 7ff76d58a9dc ("KVM: SVM: enhance MOV CR intercept handler")
Fixes cae3797a4639 ("KVM: SVM: enhance mov DR intercept handler")
Cc [email protected]
Signed-off-by Sean Christopherson <[email protected]>

Message-Id: <[email protected]>

Signed-off-by Paolo Bonzini <[email protected]>
arch/x86/kvm/svm/svm.c +4 -4
index 301792542937..857bcf3a4cda 100644
@@ -2451,7 +2451,7 @@ static int cr_interception(struct kvm_vcpu *vcpu)
 	err = 0;
 	if (cr >= 16) { /* mov to cr */
 		cr -= 16;
-		val = kvm_register_read(vcpu, reg);
+		val = kvm_register_readl(vcpu, reg);
 		trace_kvm_cr_write(cr, val);
 		switch (cr) {
 		case 0:

@@ -2497,7 +2497,7 @@ static int cr_interception(struct kvm_vcpu *vcpu)
 			kvm_queue_exception(vcpu, UD_VECTOR);
 			return 1;
 		}
-		kvm_register_write(vcpu, reg, val);
+		kvm_register_writel(vcpu, reg, val);
 		trace_kvm_cr_read(cr, val);
 	}
 	return kvm_complete_insn_gp(vcpu, err);

@@ -2563,11 +2563,11 @@ static int dr_interception(struct kvm_vcpu *vcpu)
 	dr = svm->vmcb->control.exit_code - SVM_EXIT_READ_DR0;
 	if (dr >= 16) { /* mov to DRn  */
 		dr -= 16;
-		val = kvm_register_read(vcpu, reg);
+		val = kvm_register_readl(vcpu, reg);
 		err = kvm_set_dr(vcpu, dr, val);
 	} else {
 		kvm_get_dr(vcpu, dr, &val);
-		kvm_register_write(vcpu, reg, val);
+		kvm_register_writel(vcpu, reg, val);
 	}
 
 	return kvm_complete_insn_gp(vcpu, err);
#1 lore raw

Hi Greg,

Quoted 5 lines · On Wed, May 12, 2021 at 12:43:53PM +0200, [email protected] wrote:

The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Here is the backported patch.

--
Regards
Sudip

From 516f853bf3b71f89489d94f3234b77a9961c4619 Mon Sep 17 00:00:00 2001
From: Sean Christopherson <[email protected]>
Date: Wed, 21 Apr 2021 19:21:22 -0700
Subject: [PATCH] KVM: SVM: Truncate GPR value for DR and CR accesses in
!64-bit mode

commit 0884335a2e653b8a045083aa1d57ce74269ac81d upstream.

Drop bits 63:32 on loads/stores to/from DRs and CRs when the vCPU is not in 64-bit mode. The APM states bits 63:32 are dropped for both DRs and CRs:

In 64-bit mode, the operand size is fixed at 64 bits without the need for a REX prefix. In non-64-bit mode, the operand size is fixed at 32 bits and the upper 32 bits of the destination are forced to 0.

Fixes 7ff76d58a9dc ("KVM: SVM: enhance MOV CR intercept handler")
Fixes cae3797a4639 ("KVM: SVM: enhance mov DR intercept handler")
Cc [email protected]
Signed-off-by Sean Christopherson <[email protected]>

Message-Id: <[email protected]>

Signed-off-by Paolo Bonzini <[email protected]>
Signed-off-by Sudip Mukherjee <[email protected]>
---
 arch/x86/kvm/svm/svm.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)
arch/x86/kvm/svm/svm.c +4 -4
index 9a6825feaf53..30569bbbca9a 100644
@@ -2532,7 +2532,7 @@ static int cr_interception(struct vcpu_svm *svm)
 	err = 0;
 	if (cr >= 16) { /* mov to cr */
 		cr -= 16;
-		val = kvm_register_read(&svm->vcpu, reg);
+		val = kvm_register_readl(&svm->vcpu, reg);
 		trace_kvm_cr_write(cr, val);
 		switch (cr) {
 		case 0:

@@ -2578,7 +2578,7 @@ static int cr_interception(struct vcpu_svm *svm)
 			kvm_queue_exception(&svm->vcpu, UD_VECTOR);
 			return 1;
 		}
-		kvm_register_write(&svm->vcpu, reg, val);
+		kvm_register_writel(&svm->vcpu, reg, val);
 		trace_kvm_cr_read(cr, val);
 	}
 	return kvm_complete_insn_gp(&svm->vcpu, err);

@@ -2643,11 +2643,11 @@ static int dr_interception(struct vcpu_svm *svm)
 	dr = svm->vmcb->control.exit_code - SVM_EXIT_READ_DR0;
 	if (dr >= 16) { /* mov to DRn  */
 		dr -= 16;
-		val = kvm_register_read(&svm->vcpu, reg);
+		val = kvm_register_readl(&svm->vcpu, reg);
 		err = kvm_set_dr(&svm->vcpu, dr, val);
 	} else {
 		kvm_get_dr(&svm->vcpu, dr, &val);
-		kvm_register_write(&svm->vcpu, reg, val);
+		kvm_register_writel(&svm->vcpu, reg, val);
 	}
 
 	return kvm_complete_insn_gp(&svm->vcpu, err);
Signature · 1 line
2.30.2
maintainer
#2 lore raw
Quoted 10 lines · Sudip Mukherjee

Hi Greg,

Quoted 5 lines · On Wed, May 12, 2021 at 12:43:53PM +0200, [email protected] wrote:

The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Here is the backported patch.

All four backports look good, thanks!

author maintainer
#3 lore raw
Quoted 5 lines · Sean Christopherson
Quoted 4 lines · Sudip Mukherjee

Hi Greg,

Quoted 1 line · On Wed, May 12, 2021 at 12:43:53PM +0200, [email protected] wrote:
Quoted 8 lines
Quoted 6 lines
Quoted 4 lines

The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

Here is the backported patch.

All four backports look good, thanks!

All now queued up, thanks.

greg k-h