From nobody Wed Apr 8 03:07:42 2026 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C79DB3F20E4 for ; Tue, 10 Mar 2026 22:04:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773180260; cv=none; b=I9YM55OSLjW5En6QD2zcZ2pUwebCLU8w/2uQlEgdD2rQdG2e1JLmvSm4W76bAjwoYXBxRLIo2cC4JzCMw76cPIcG5VdANcZsko3SfHhYm8wUZ7P5npNvSHByDZTNWaPUKnTkXM96Bm0AT1e7yxJqwA5GuXPKKdMPrarOPje5cUI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773180260; c=relaxed/simple; bh=lE0K9Je/w0ZhiGDqNCv8UqndQifIY5jPoFxLd4PUljQ=; h=Date:Mime-Version:Message-ID:Subject:From:To:Cc:Content-Type; b=RDVFL6bK2fzz04hVpI5hgGokxu7l8BdwXl+E3fudaPgr7x68OOO7tjViOmXvFW7jVmi7V6rX5xvHl9i9oh9qP85WeZze0kQ2MxekNsZpsQ02+kGUU+G+xRg0uzOkbvjEKqsTdLpN7ccqFTRVb0LkV8sCQWcXmnQmyHrWrxPXfQc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=iOy3zJ1R; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="iOy3zJ1R" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2aeaabedbc3so36784345ad.3 for ; Tue, 10 Mar 2026 15:04:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1773180256; x=1773785056; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:reply-to:from:to:cc :subject:date:message-id:reply-to; bh=0NmflkMmCh1+M25HJ2VtiJQJbU+JaF3SO+uDwG5B5XM=; b=iOy3zJ1Rs+lfLKhM2oyBnkXKIxE5dGy4NwIdXMTaf/Rsjqeq0AUdt2uadaFXUGTxtJ MK486YSck1HLuVlY4qUiSpsZC67kKGc/KwNDeclPtqCYhYdV+iD1Jt+UHCHtkv6OHaR3 wvc73ykQhpyPlBqXJdf835gO6Y26mrJYShVAqe+Z/62oOyK4Uwbr1RcXGfsO5O0mE9Ba CtMgNkcSKGCGZSCKxms/P2+M5qW3PRszDxqa1S/r2z5Os50Dlybj25BrSpuXkfGZAtPa WPxzqC5nACDBPCLyV0sdITnPaxKZsdrI5vVwZMmjDvZutKp7NYO0mmAARMil/dyKBeDP ve3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1773180256; x=1773785056; h=cc:to:from:subject:message-id:mime-version:date:reply-to :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0NmflkMmCh1+M25HJ2VtiJQJbU+JaF3SO+uDwG5B5XM=; b=dUn1c1uzUsW81i9cp/Wj9PU8AR9d+I3OXNElR5XjIOTtyfOYx9a8c6ynnlOoT5L9sM PPXX5u+8tkdJt6t1zQIIeausOtbR4vT5rg0qiHmY8CvT80tan6cbxiCzRMgHNMQnrCnO oPyKBeudweMoukCZ8rqTM8HLaVEm0lnug5/aqcNoZUexI0+IDqoSCv5+5MscRQqa5G4i fIUNaAMGLJQymut6O9zUDZbWgVb2SbcD4sHmHZsnFweAmYiVeBwCK2BJX4qp2UiyfX3m jEz8+kUfNKlIdDpHxhOgu/bunBjvIsLbsWhbUsQVEhb3ArK2hXBKGWzPuBLneqDk5it+ gebQ== X-Forwarded-Encrypted: i=1; AJvYcCUdsylGV0LllN73+hmYR9btCBvgHLVWbacaWZgfO5N9tIcTW0yjH69sy3fdzm+Jikok6xgSdmasMEPvJIg=@vger.kernel.org X-Gm-Message-State: AOJu0YyKnndd7i4GpiDJJ9xjFTbO2Fo+gYLqyiq2TVZ1zd8ExVbaQEIu yjHRUxYN3rh0AlG/Q+1WTAOeeolPngItid6jrOkZhVzfdQ6N4DI9PMfexofwdvJHZ/w8SkoqazD IPobI+A== X-Received: from plhz12.prod.google.com ([2002:a17:902:d9cc:b0:2ab:192e:f70d]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:174e:b0:2ae:5104:571e with SMTP id d9443c01a7336-2aeae76fa46mr2948195ad.9.1773180255942; Tue, 10 Mar 2026 15:04:15 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 10 Mar 2026 15:04:14 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 X-Mailer: git-send-email 2.53.0.473.g4a7958ca14-goog Message-ID: <20260310220414.2569208-1-seanjc@google.com> Subject: [PATCH] KVM: SVM: Add a helper to get LBR field pointer to dedup MSR accesses From: Sean Christopherson To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Yosry Ahmed Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add a helper to get a pointer to the corresponding VMCB field given an LBR MSR index, and use it to dedup the handling in svm_{g,s}et_msr(). No functional change intended. Suggested-by: Yosry Ahmed Signed-off-by: Sean Christopherson Reviewed-by: Yosry Ahmed --- arch/x86/kvm/svm/svm.c | 48 +++++++++++++++++------------------------- 1 file changed, 19 insertions(+), 29 deletions(-) diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 3407deac90bd..88999b6fc8a3 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2750,6 +2750,23 @@ static int svm_get_feature_msr(u32 msr, u64 *data) return 0; } =20 +static __always_inline u64 *svm_vmcb_lbr(struct vcpu_svm *svm, u32 msr) +{ + switch (msr) { + case MSR_IA32_LASTBRANCHFROMIP: + return &svm->vmcb->save.br_from; + case MSR_IA32_LASTBRANCHTOIP: + return &svm->vmcb->save.br_to; + case MSR_IA32_LASTINTFROMIP: + return &svm->vmcb->save.last_excp_from; + case MSR_IA32_LASTINTTOIP: + return &svm->vmcb->save.last_excp_to; + default: + break; + } + BUILD_BUG(); +} + static bool sev_es_prevent_msr_access(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { @@ -2826,16 +2843,10 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struc= t msr_data *msr_info) msr_info->data =3D lbrv ? svm->vmcb->save.dbgctl : 0; break; case MSR_IA32_LASTBRANCHFROMIP: - msr_info->data =3D lbrv ? svm->vmcb->save.br_from : 0; - break; case MSR_IA32_LASTBRANCHTOIP: - msr_info->data =3D lbrv ? svm->vmcb->save.br_to : 0; - break; case MSR_IA32_LASTINTFROMIP: - msr_info->data =3D lbrv ? svm->vmcb->save.last_excp_from : 0; - break; case MSR_IA32_LASTINTTOIP: - msr_info->data =3D lbrv ? svm->vmcb->save.last_excp_to : 0; + msr_info->data =3D lbrv ? *svm_vmcb_lbr(svm, msr_info->index) : 0; break; case MSR_VM_HSAVE_PA: msr_info->data =3D svm->nested.hsave_msr; @@ -3111,35 +3122,14 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struc= t msr_data *msr) svm_update_lbrv(vcpu); break; case MSR_IA32_LASTBRANCHFROMIP: - if (!lbrv) - return KVM_MSR_RET_UNSUPPORTED; - if (!msr->host_initiated) - return 1; - svm->vmcb->save.br_from =3D data; - vmcb_mark_dirty(svm->vmcb, VMCB_LBR); - break; case MSR_IA32_LASTBRANCHTOIP: - if (!lbrv) - return KVM_MSR_RET_UNSUPPORTED; - if (!msr->host_initiated) - return 1; - svm->vmcb->save.br_to =3D data; - vmcb_mark_dirty(svm->vmcb, VMCB_LBR); - break; case MSR_IA32_LASTINTFROMIP: - if (!lbrv) - return KVM_MSR_RET_UNSUPPORTED; - if (!msr->host_initiated) - return 1; - svm->vmcb->save.last_excp_from =3D data; - vmcb_mark_dirty(svm->vmcb, VMCB_LBR); - break; case MSR_IA32_LASTINTTOIP: if (!lbrv) return KVM_MSR_RET_UNSUPPORTED; if (!msr->host_initiated) return 1; - svm->vmcb->save.last_excp_to =3D data; + *svm_vmcb_lbr(svm, ecx) =3D data; vmcb_mark_dirty(svm->vmcb, VMCB_LBR); break; case MSR_VM_HSAVE_PA: base-commit: 5128b972fb2801ad9aca54d990a75611ab5283a9 --=20 2.53.0.473.g4a7958ca14-goog