From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-238.mta1.migadu.com [95.215.58.238]) (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 A15A54503E2 for ; Mon, 31 Aug 2026 16:34:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.238 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788194068; cv=none; b=L4Bmi3OfPk30pYiRsGibwQ7Fel5axHok2Xsd4hY7Dr1BaLWJ2bCtEXdRAO6JIMAG4tw41eTU2yhp6EOPhi5FDbnLLGfiNW42AuppM4i+L1SMKXYFHtITpuecTPPo2tAnGvVW7vLxU8unJLMcJvLzmIanMUsuxbnwlkSRYd7cJco= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788194068; c=relaxed/simple; bh=xkq1pK+JQIT20fKqr7d//bEzBjwmUGbNVIrU7IeZkOU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=P5tBjKQ0nKVW3ryd5v4Rv2wuogydPuHYGnffRO6IFODgZYCwR4K/AcuR+kjFXTdWox2mG0/Dxvwt0RY1cA0yer6dtFa9PXhKq+f44WKRnT2bmvxAv0nbQgN7pwUlh1zN6bT4tYZxU0zGi4p9iT9wbuMK0wPzN5CMFJnq8psy45o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=RfKXUbuf; arc=none smtp.client-ip=95.215.58.238 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="RfKXUbuf" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=xkq1pK+JQIT20fKqr7d//bEzBjwmUGbNVIrU7IeZkOU=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1788194064; v=1; x=1788798864; b=RfKXUbufu2N5juLudrfplKRLh7fG3qGc+sJpyLEQOh+RvIV5P+UGjMmiHXV6s7pys0tXjHIH iITcCpYB3o9w8FyXiW/jtLCFTVgc4I762BOubKmVEnrHj7GBj6VSUo68CVgH5K/wH4YSKjaFhDd 7kUAL8XAE5bYEDGVUlj+LoUQ= X-Envelope-To: linux-kernel@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 83b96d24d68e6398; Mon, 31 Aug 2026 16:34:24 +0000 X-Mizu-Trace-ID: 83b96d24d68e6398 X-Migadu-Flow: FLOW_OUT From: Fuad Tabba To: Marc Zyngier , Oliver Upton , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Vincent Donnefort , Quentin Perret , Fuad Tabba Subject: [PATCH 03/17] KVM: arm64: Reject the PVTIME vCPU attribute for protected VMs Date: Mon, 31 Aug 2026 17:34:07 +0100 Message-Id: <20260831163421.272420-4-fuad.tabba@linux.dev> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20260831163421.272420-1-fuad.tabba@linux.dev> References: <20260831163421.272420-1-fuad.tabba@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit pKVM currently does not support steal time for protected guests: KVM_CAP_STEAL_TIME reports 0 for them. The host still accepts the KVM_ARM_VCPU_PVTIME_CTRL attribute, whose IPA would point kvm_update_stolen_time() at the guest's private memory on every vCPU load. Return -EPERM for the attribute group instead. Signed-off-by: Fuad Tabba --- arch/arm64/kvm/guest.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c index b01d6622b8720..23f725e2cf745 100644 --- a/arch/arm64/kvm/guest.c +++ b/arch/arm64/kvm/guest.c @@ -916,6 +916,10 @@ int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu, ret = kvm_arm_timer_set_attr(vcpu, attr); break; case KVM_ARM_VCPU_PVTIME_CTRL: + /* Steal time is not offered to protected guests. */ + if (kvm_vm_is_protected(vcpu->kvm)) + return -EPERM; + ret = kvm_arm_pvtime_set_attr(vcpu, attr); break; default: @@ -939,6 +943,9 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu, ret = kvm_arm_timer_get_attr(vcpu, attr); break; case KVM_ARM_VCPU_PVTIME_CTRL: + if (kvm_vm_is_protected(vcpu->kvm)) + return -EPERM; + ret = kvm_arm_pvtime_get_attr(vcpu, attr); break; default: @@ -962,6 +969,9 @@ int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu, ret = kvm_arm_timer_has_attr(vcpu, attr); break; case KVM_ARM_VCPU_PVTIME_CTRL: + if (kvm_vm_is_protected(vcpu->kvm)) + return -EPERM; + ret = kvm_arm_pvtime_has_attr(vcpu, attr); break; default: -- 2.39.5