From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0752C43B4A6; Mon, 3 Aug 2026 13:47:36 +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=1785764859; cv=none; b=CyV5KLVd2bNvoBgJQ0H6wOGpVCY736RKZogrLzO4W/Wcq43CznD8dkv22qr2Sm0yW/VYO4sERx/wXfLT/ON7dwGo1NV698eaTfiEcXErAKOaqIJnEQdafFJsFelYMN1Y2PBsRjDA+nbRQbYdRb5J0ihlHcHxJr47hj4P32jnM3o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785764859; c=relaxed/simple; bh=XwWksQKK5JHoi1/bsiLim1Ro0hK67xh7Nvsm2bnB00A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=R0kDYhMu/L1+dbYQx3XF83BwwTBZUC8h4TRqnAGIiiWD+BVtKN/UpqH+z/Hb8qpPoey8nyG9CnxSOrEZoBACL9YY6A7YFc9cGa2jf2MXWhROLGhRFHssKnxOcew3f8+ss17SiPsTi3Zc7Or/Ej5BlYf6RSJPfZcqIqMeMF4pZd4= 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; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=KRcutHS6; 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 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="KRcutHS6" 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 4BBB31655; Mon, 3 Aug 2026 06:47:32 -0700 (PDT) Received: from e122027.cambridge.arm.com (e122027.cambridge.arm.com [10.1.25.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2DA923F66F; Mon, 3 Aug 2026 06:47:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1785764856; bh=XwWksQKK5JHoi1/bsiLim1Ro0hK67xh7Nvsm2bnB00A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KRcutHS6jo2IEonPBEtf0bVzFKWBrrVHuYAMNQw4/yXHJI7ZmocJa7bh08of9PeVM K/bQKGpM8ILOlNuGLgc7Zl/lxBuFMCelKCAXtH49AzvWeEbcFfBFZcR9lWNh3Qa9// Alg96p+r5ajufnOUfjSMJTh/W+18TrMEUCKU89Ek= 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 , "Aneesh Kumar K . V" , Emi Kisanuki , Vishal Annapurve , WeiLin.Chang@arm.com, Lorenzo Pieralisi , Steven Price Subject: [PATCH v16 42/45] KVM: arm64: CCA: Provide register list for unfinalized RECs Date: Mon, 3 Aug 2026 14:43:58 +0100 Message-ID: <20260803134403.80630-43-steven.price@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260803134403.80630-1-steven.price@arm.com> References: <20260803134403.80630-1-steven.price@arm.com> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Gavin Shan --- arch/arm64/kvm/arm.c | 4 ---- arch/arm64/kvm/guest.c | 10 +++++----- 2 files changed, 5 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 3242108be7c5..fd4e13ff17cf 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1967,10 +1967,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp, if (unlikely(!kvm_vcpu_initialized(vcpu))) break; - r = -EPERM; - if (!kvm_arm_vcpu_is_finalized(vcpu)) - break; - r = -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 452cf5d3152e..128fec56993a 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -617,8 +617,8 @@ static unsigned long num_sve_regs(const struct kvm_vcpu *vcpu) if (!vcpu_has_sve(vcpu)) return 0; - /* Policed by KVM_GET_REG_LIST: */ - WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu)); + if (!kvm_arm_vcpu_sve_finalized(vcpu)) + return 1; /* KVM_REG_ARM64_SVE_VLS */ return slices * (SVE_NUM_PREGS + SVE_NUM_ZREGS + 1 /* FFR */) + 1; /* KVM_REG_ARM64_SVE_VLS */ @@ -635,9 +635,6 @@ static int copy_sve_reg_indices(const struct kvm_vcpu *vcpu, if (!vcpu_has_sve(vcpu)) return 0; - /* Policed by KVM_GET_REG_LIST: */ - WARN_ON(!kvm_arm_vcpu_sve_finalized(vcpu)); - /* * Enumerate this first, so that userspace can save/restore in * the order reported by KVM_GET_REG_LIST: @@ -647,6 +644,9 @@ static int copy_sve_reg_indices(const struct kvm_vcpu *vcpu, return -EFAULT; ++num_regs; + if (!kvm_arm_vcpu_sve_finalized(vcpu)) + return num_regs; + for (i = 0; i < slices; i++) { for (n = 0; n < SVE_NUM_ZREGS; n++) { reg = KVM_REG_ARM64_SVE_ZREG(n, i); -- 2.43.0