From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6F88D2D47E8 for ; Mon, 24 Nov 2025 19:02:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764010921; cv=none; b=umsBqbOcADxxgC42X8s7ssCJ+uZdKL/bSO6+eqma7td2GX5uHoaNDezvhFDNCfFouAuufLo7IqQctZwy+4L7xMl4Al2HIQOZexT4ZgCrXhzhJpSEACRmovV29XLJeEjitlqk2wlck28oYkTY88f+UwzoodvKetuAsV3s0n354i4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764010921; c=relaxed/simple; bh=+qPsO4bgGQzYvJXWOcCeqn9nu6ZNp6hByCg2pofBoTw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FJ7206iMN/R24fkbU7Df7db1+n62Dnbrlia96doylJBhiZsS+U3Nh6bygZj8f6fHKJT6fq2iHVyYYpp4zQcDtccyZ6dP3LrSfaRWFsLBJbK8RhkL7ptdNIM3+iRDEeHzJMI4U3ZbmnzZr48isIMAQkN93sr55k3VhtaP50aQ4Zc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TCwO/XtV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TCwO/XtV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 322BEC19421; Mon, 24 Nov 2025 19:02:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764010921; bh=+qPsO4bgGQzYvJXWOcCeqn9nu6ZNp6hByCg2pofBoTw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TCwO/XtVD36g9VgO+x/ZsqYDrgOes4jGeJuqh6XDCU1aAQM3Dau6Fo/xs3QHut/qC n5UbNEB/HXdifO19kvoZ39slnJEdxRgI37jjs3JRC576hsaJW6XumTwbn9xOJgHb1V jRlYjGHpWFtPFNCRZpCXNPzF1jJfXYUOOp3CsM/JFs3ycPUbz7kHdPSvXrVWhHAk+u uyLQcDSY1hKmRiD0di5BbEmtBz6Cy0E8SV/ysYQlR7YVzKKd8GRt/UjMu7J0KbbyI+ m4LQSMnVjgCNF0/7ic5VBXF0hfJjGlF8qZoY+0xII3h1c1M4adL8rOuO/rXgidPg3u 6QFK0sx7FQdkA== From: Oliver Upton To: kvmarm@lists.linux.dev Cc: Marc Zyngier , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Oliver Upton Subject: [PATCH v3 08/15] KVM: arm64: Handle endianness in read helper for emulated PTW Date: Mon, 24 Nov 2025 11:01:50 -0800 Message-ID: <20251124190158.177318-9-oupton@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20251124190158.177318-1-oupton@kernel.org> References: <20251124190158.177318-1-oupton@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Implementing FEAT_HAFDBS means adding another descriptor accessor that needs to deal with the guest-configured endianness. Prepare by moving the endianness handling into the read accessor and out of the main body of the S1/S2 PTWs. Signed-off-by: Oliver Upton --- arch/arm64/kvm/at.c | 25 +++++++++++++++++++------ arch/arm64/kvm/nested.c | 32 ++++++++++++++++++++------------ 2 files changed, 39 insertions(+), 18 deletions(-) diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c index be26d5aa668c..a295a37dd3b1 100644 --- a/arch/arm64/kvm/at.c +++ b/arch/arm64/kvm/at.c @@ -362,6 +362,24 @@ static int setup_s1_walk(struct kvm_vcpu *vcpu, struct s1_walk_info *wi, return -EFAULT; } +static int kvm_read_s1_desc(struct kvm_vcpu *vcpu, u64 pa, u64 *desc, + struct s1_walk_info *wi) +{ + u64 val; + int r; + + r = kvm_read_guest(vcpu->kvm, pa, &val, sizeof(val)); + if (r) + return r; + + if (wi->be) + *desc = be64_to_cpu((__force __be64)val); + else + *desc = le64_to_cpu((__force __le64)val); + + return 0; +} + static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi, struct s1_walk_result *wr, u64 va) { @@ -414,17 +432,12 @@ static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi, return ret; } - ret = kvm_read_guest(vcpu->kvm, ipa, &desc, sizeof(desc)); + ret = kvm_read_s1_desc(vcpu, ipa, &desc, wi); if (ret) { fail_s1_walk(wr, ESR_ELx_FSC_SEA_TTW(level), false); return ret; } - if (wi->be) - desc = be64_to_cpu((__force __be64)desc); - else - desc = le64_to_cpu((__force __le64)desc); - /* Invalid descriptor */ if (!(desc & BIT(0))) goto transfault; diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c index 94eff8307aad..75d26c0ba3e0 100644 --- a/arch/arm64/kvm/nested.c +++ b/arch/arm64/kvm/nested.c @@ -197,9 +197,26 @@ static int check_output_size(struct s2_walk_info *wi, phys_addr_t output) return 0; } -static int read_guest_s2_desc(struct kvm_vcpu *vcpu, phys_addr_t pa, u64 *desc) +static int read_guest_s2_desc(struct kvm_vcpu *vcpu, phys_addr_t pa, u64 *desc, + struct s2_walk_info *wi) { - return kvm_read_guest(vcpu->kvm, pa, desc, sizeof(*desc)); + u64 val; + int r; + + r = kvm_read_guest(vcpu->kvm, pa, &val, sizeof(val)); + if (r) + return r; + + /* + * Handle reversedescriptors if endianness differs between the + * host and the guest hypervisor. + */ + if (wi->be) + *desc = be64_to_cpu((__force __be64)val); + else + *desc = le64_to_cpu((__force __le64)val); + + return 0; } /* @@ -260,19 +277,10 @@ static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, phys_addr_t ipa, >> (addr_bottom - 3); paddr = base_addr | index; - ret = read_guest_s2_desc(vcpu, paddr, &desc); + ret = read_guest_s2_desc(vcpu, paddr, &desc, wi); if (ret < 0) return ret; - /* - * Handle reversedescriptors if endianness differs between the - * host and the guest hypervisor. - */ - if (wi->be) - desc = be64_to_cpu((__force __be64)desc); - else - desc = le64_to_cpu((__force __le64)desc); - /* Check for valid descriptor at this point */ if (!(desc & 1) || ((desc & 3) == 1 && level == 3)) { out->esr = compute_fsc(level, ESR_ELx_FSC_FAULT); -- 2.47.3