linux-kernel - [PATCH kernel 7/9] KVM: SEV-ES: Eliminate #DB intercept when DebugSwap enabled

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Message-ID: <20230615063757.3039121-8-aik@amd.com>
Date:   Thu, 15 Jun 2023 16:37:55 +1000
From:   Alexey Kardashevskiy <aik@....com>
To:     <kvm@...r.kernel.org>
CC:     <x86@...nel.org>, <linux-kernel@...r.kernel.org>,
        Tom Lendacky <thomas.lendacky@....com>,
        Sean Christopherson <seanjc@...gle.com>,
        "Alexey Kardashevskiy" <aik@....com>
Subject: [PATCH kernel 7/9] KVM: SEV-ES: Eliminate #DB intercept when DebugSwap enabled

Disable #DB for SEV-ES guests when DebugSwap is enabled. There is no point
in such intercept as KVM does not allow guest debug for SEV-ES guests.

Signed-off-by: Alexey Kardashevskiy <aik@....com>
---
Changes:
v6:
* new to the series
---
 arch/x86/kvm/svm/sev.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index abc502ce7871..9c43cbdab022 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -3000,6 +3000,8 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
 		vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ);
 		vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE);
 		recalc_intercepts(svm);
+	} else {
+		clr_exception_intercept(svm, DB_VECTOR);
 	}
 
 	/* Can't intercept XSETBV, HV can't modify XCR0 directly */
-- 
2.40.1