From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 82360F34C65 for ; Mon, 13 Apr 2026 16:55:01 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wCKYK-0007Y0-1K; Mon, 13 Apr 2026 12:54:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wCKXl-0006wM-74 for qemu-devel@nongnu.org; Mon, 13 Apr 2026 12:53:50 -0400 Received: from p-west2-cluster1-host6-snip4-7.eps.apple.com ([57.103.68.60] helo=outbound.mr.icloud.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wCKXj-0005bA-RA for qemu-devel@nongnu.org; Mon, 13 Apr 2026 12:53:48 -0400 Received: from outbound.mr.icloud.com (unknown [127.0.0.2]) by p00-icloudmta-asmtp-us-west-2a-10-percent-1 (Postfix) with ESMTPS id 1F0DB1800EBA; Mon, 13 Apr 2026 16:53:44 +0000 (UTC) Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr; s=sig1; t=1776099226; x=1778691226; bh=SCqUAJvB1zqKRh44vHU0QIqywz/suuWsKXqtx/ZiPkM=; h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme; b=KM9nd+mzg2DuAAMpzJ9/tpGllWc3XQK533a1LrsD8mDgbRDK6UwCAo6A9hfWAtKYH6+Dp+S6jjJYyECFP5cjDTPYs+8MPgewGZMjPoTNx60gYi8Sv4c8/A3+T9Bcexq9w5IqpLl0NsxVabhltdVqqQB9M7niXcgtrY1Pk219/DYHqQVf3eNQPmlcw+e+T7R0GITOmcmwUg81Ge0GP8H7gIwO8k/F1hPP6fbIc80zyIyPQaOwxeqmSKXNwWEpo1ILfXzNQNy8OKYXyoRC93vpiKJZ1kLV/Zo7HiePfomEpeH56zWVMOt1V3qODq0zDyOAozx0GlNf0J4pZs4t7VodoA== mail-alias-created-date: 1752046281608 Received: from localhost.localdomain (unknown [17.57.152.38]) by p00-icloudmta-asmtp-us-west-2a-10-percent-1 (Postfix) with ESMTPSA id 4EA1118023A5; Mon, 13 Apr 2026 16:53:41 +0000 (UTC) From: Mohamed Mediouni To: qemu-devel@nongnu.org Cc: "Michael S. Tsirkin" , Pedro Barbuda , Mohamed Mediouni , Paolo Bonzini , Zhao Liu , Roman Bolshakov , Wei Liu , Phil Dennis-Jordan Subject: [PATCH v11 14/15] hw/intc: apic: disallow APIC reads when disabled Date: Mon, 13 Apr 2026 18:52:16 +0200 Message-ID: <20260413165217.47105-15-mohamed@unpredictable.fr> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20260413165217.47105-1-mohamed@unpredictable.fr> References: <20260413165217.47105-1-mohamed@unpredictable.fr> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-ORIG-GUID: NcsbE5_Bg3kp2_1-i5uRuQEyXNbecz4D X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNDEzMDE2NiBTYWx0ZWRfX43q0zF5F96mb 0HcNCH5sSnKnfk71SLJ4kUIbnqLPwWPZVS8snrG+Zqwcv5ACnOs/DzVYxJY0Bmw40KWLCXr7oEq 81rZFy3aAmoyav2R1ykUegP4kEBGJcrS4rpcgs2eTV6dyWxseEikdgKE3/18Wzm7JOmPHdPmKeH ovyU4tA1AMoYZKLb20WmqAT3UCy2Llb4uHA48bER8ZdlmRP/GDjdOUvXo91RWRGWFjw20vLV2uG 5Y7as/wMsVURBZglsKWkKItPvDob4tGmx65f5ySX5qOMsDinUK2qtT2q+DFFquUkb0m2y4FYtuJ R0cB8E0IhuIU1jDie1V0/V+0LOLpjBtZUoFLuXUJQX89z2f86qqgpNe1MR6OBY= X-Authority-Info-Out: v=2.4 cv=RpTI7SmK c=1 sm=1 tr=0 ts=69dd1f9a cx=c_apl:c_pps:t_out a=9OgfyREA4BUYbbCgc0Y0oA==:117 a=9OgfyREA4BUYbbCgc0Y0oA==:17 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=Sz3nRv2TKcqVAncp5HQA:9 X-Proofpoint-GUID: NcsbE5_Bg3kp2_1-i5uRuQEyXNbecz4D X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-04-13_03,2026-04-13_04,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 lowpriorityscore=0 adultscore=0 malwarescore=0 phishscore=0 bulkscore=0 mlxlogscore=800 mlxscore=0 suspectscore=0 clxscore=1030 classifier=spam authscore=0 adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000 definitions=main-2604130166 Received-SPF: pass client-ip=57.103.68.60; envelope-from=mohamed@unpredictable.fr; helo=outbound.mr.icloud.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org !APICBASE_ENABLE + attempting to read xAPIC registers is not an allowed combination. And neither is x2APIC enabled + attempting to read xAPIC registers Signed-off-by: Mohamed Mediouni --- hw/intc/apic.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/hw/intc/apic.c b/hw/intc/apic.c index 8766ed00b9..c09dddef39 100644 --- a/hw/intc/apic.c +++ b/hw/intc/apic.c @@ -875,6 +875,15 @@ static uint64_t apic_mem_read(void *opaque, hwaddr addr, unsigned size) return -1; } + /* if the xAPIC is disabled, return early. */ + if (!(s->apicbase & MSR_IA32_APICBASE_ENABLE)) { + return 0xffffffff; + } + + if (s->apicbase & MSR_IA32_APICBASE_EXTD) { + return 0xffffffff; + } + index = (addr >> 4) & 0xff; apic_register_read(s, index, &val); -- 2.50.1 (Apple Git-155)