From nobody Tue Feb 10 04:12:32 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CFF801B3B0D; Wed, 21 Aug 2024 15:41:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724254895; cv=none; b=jMtk2C+N/DjRA5+AAEUwJJa0fXUCDffxPelyfTUFMpV6nBiAHlRT3C2VxH4Ggg7G3jlWugtMAJkWLgCyzQKTZ+Eby1pBdGgFhpXt7D0aZ2KkB4kIfSgJH5h8WKyr15foPR26VxJTSQOlahPP0TKWFUYOUrrUQPq1TS/+1ZUJaqE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724254895; c=relaxed/simple; bh=nZPcRjWloYEgiSPwmpN4Ipt++TFArXygZXfACNgCinE=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Vgp2mZlvy6ko3beCIN/Z/9fq1isDvZw6uPQE0hJxs+J04560+rwXkk4+DdW7F0bIcV0qHbtiuIE0aWvMEujlsn181QWKEhWRBBHyhgeBRQq+/KRIEDW415y3VcciWX7lVPQz3f0AvWZIHgJo4YiwLjfvV70NUP1f3yXxr7s+yPY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 88264DA7; Wed, 21 Aug 2024 08:41:59 -0700 (PDT) Received: from e122027.cambridge.arm.com (e122027.cambridge.arm.com [10.1.37.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7B6343F73B; Wed, 21 Aug 2024 08:41:29 -0700 (PDT) From: Steven Price To: kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: Jean-Philippe Brucker , Catalin Marinas , Marc Zyngier , Will Deacon , James Morse , Oliver Upton , Suzuki K Poulose , Zenghui Yu , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Joey Gouly , Alexandru Elisei , Christoffer Dall , Fuad Tabba , linux-coco@lists.linux.dev, Ganapatrao Kulkarni , Gavin Shan , Shanker Donthineni , Alper Gun , Steven Price Subject: [PATCH v4 40/43] arm64: RME: Provide register list for unfinalized RME RECs Date: Wed, 21 Aug 2024 16:38:41 +0100 Message-Id: <20240821153844.60084-41-steven.price@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240821153844.60084-1-steven.price@arm.com> References: <20240821153844.60084-1-steven.price@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Jean-Philippe Brucker KVM_GET_REG_LIST should not be called before SVE is finalized. The ioctl handler currently returns -EPERM in this case. But because it uses kvm_arm_vcpu_is_finalized(), it now also rejects the call for unfinalized REC even though finalizing the REC can only be done late, after Realm descriptor creation. Move the check to copy_sve_reg_indices(). One adverse side effect of this change is that a KVM_GET_REG_LIST call that only probes for the array size will now succeed even if SVE is not finalized, but that seems harmless since the following KVM_GET_REG_LIST with the full array will fail. Signed-off-by: Jean-Philippe Brucker Signed-off-by: Steven Price --- arch/arm64/kvm/arm.c | 4 ---- arch/arm64/kvm/guest.c | 9 +++------ 2 files changed, 3 insertions(+), 10 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index bd79a928d036..05d9062470c2 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1843,10 +1843,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp, if (unlikely(!kvm_vcpu_initialized(vcpu))) break; =20 - r =3D -EPERM; - if (!kvm_arm_vcpu_is_finalized(vcpu)) - break; - r =3D -EFAULT; if (copy_from_user(®_list, user_list, sizeof(reg_list))) break; diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index e00b72fba33d..b12b5e4ddd8c 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -653,12 +653,9 @@ static unsigned long num_sve_regs(const struct kvm_vcp= u *vcpu) { const unsigned int slices =3D vcpu_sve_slices(vcpu); =20 - if (!vcpu_has_sve(vcpu)) + if (!vcpu_has_sve(vcpu) || !kvm_arm_vcpu_sve_finalized(vcpu)) return 0; =20 - /* Policed by KVM_GET_REG_LIST: */ - WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu)); - return slices * (SVE_NUM_PREGS + SVE_NUM_ZREGS + 1 /* FFR */) + 1; /* KVM_REG_ARM64_SVE_VLS */ } @@ -674,8 +671,8 @@ static int copy_sve_reg_indices(const struct kvm_vcpu *= vcpu, if (!vcpu_has_sve(vcpu)) return 0; =20 - /* Policed by KVM_GET_REG_LIST: */ - WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu)); + if (!kvm_arm_vcpu_sve_finalized(vcpu)) + return -EPERM; =20 /* * Enumerate this first, so that userspace can save/restore in --=20 2.34.1