{"id":2226919,"url":"http://patchwork.ozlabs.org/api/patches/2226919/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260422214225.2242-15-mohamed@unpredictable.fr/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260422214225.2242-15-mohamed@unpredictable.fr>","list_archive_url":null,"date":"2026-04-22T21:42:02","name":"[v3,14/37] hw/intc: apic: disallow APIC reads when disabled","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"4b530832baccd204d18491eb1e9bd1db2ee977a9","submitter":{"id":91318,"url":"http://patchwork.ozlabs.org/api/people/91318/?format=json","name":"Mohamed Mediouni","email":"mohamed@unpredictable.fr"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260422214225.2242-15-mohamed@unpredictable.fr/mbox/","series":[{"id":501116,"url":"http://patchwork.ozlabs.org/api/series/501116/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=501116","date":"2026-04-22T21:41:48","name":"[v3,01/37] target/i386: emulate: include name of unhandled instruction","version":3,"mbox":"http://patchwork.ozlabs.org/series/501116/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2226919/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2226919/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=unpredictable.fr header.i=@unpredictable.fr\n header.a=rsa-sha256 header.s=sig1 header.b=FYHd81Py;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; helo=lists1p.gnu.org;\n envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n receiver=patchwork.ozlabs.org)"],"Received":["from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17])\n\t(using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4g1CRp1YYrz1yDD\n\tfor ; Thu, 23 Apr 2026 07:44:38 +1000 (AEST)","from localhost ([::1] helo=lists1p.gnu.org)\n\tby lists1p.gnu.org with esmtp (Exim 4.90_1)\n\t(envelope-from )\n\tid 1wFfLY-00083G-6T; Wed, 22 Apr 2026 17:43:00 -0400","from eggs.gnu.org ([2001:470:142:3::10])\n by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)\n (Exim 4.90_1) (envelope-from )\n id 1wFfLW-00082K-GX\n for qemu-devel@nongnu.org; Wed, 22 Apr 2026 17:42:58 -0400","from p-east2-cluster1-host11-snip4-10.eps.apple.com ([57.103.76.53]\n helo=outbound.st.icloud.com)\n by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)\n (Exim 4.90_1) (envelope-from )\n id 1wFfLV-0007G8-5c\n for qemu-devel@nongnu.org; Wed, 22 Apr 2026 17:42:58 -0400","from outbound.st.icloud.com (unknown [127.0.0.2])\n by p00-icloudmta-asmtp-us-east-1a-100-percent-1 (Postfix) with ESMTPS id\n 017F9180096A; Wed, 22 Apr 2026 21:42:55 +0000 (UTC)","from localhost.localdomain (unknown [17.42.251.67])\n by p00-icloudmta-asmtp-us-east-1a-100-percent-1 (Postfix) with ESMTPSA id\n 431CC1800230; Wed, 22 Apr 2026 21:42:54 +0000 (UTC)"],"X-ICL-Out-Info":"\n HUtFAUMHWwJACUgBTUQeDx5WFlZNRAJCTQFIHV8DWRxBAUkdXw9LVxQEFVwFVgZXFHkNXR1FDlYZWgxSD1sOHBZLWFUJCgZdGFgVVgl3HlwASx1XBFQfUxJVHR0LRUtAEwRJAU1fDl4fBBdGGVUERx5dVkAZGQJRHFYNV0NUBF9QSQxBUGxaAEcXSB1dGVlvUF0cDhhZG0AVXRFQGVYJXhUXHkFNWgJWTQVKA18BWwZCC0oCWQVZB14LSgdfGloHXVQXWwxaDlYwTBZDH1IPWxNNGVEBUkVUAgdYRxRHDg8TTAtHAlo0Vh9UGVoD","Dkim-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr;\n s=sig1; t=1776894176; x=1779486176;\n bh=ZKPoujWieITU4lFOoYMwoz+Ev2hRigYtFeWxrkrjtmk=;\n h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme;\n b=FYHd81PyOQQMFwzULiOUV6YrlrcCWSR86Y2vTU+3E7FTBXjQ0QJuONoPxFWYRyVcfXfPixyloA3FtEZDTP7SBJ15mj0c0LRaEQILYYPOwh8zXSIO6surH7lKJMqOC4mtXt6BQK9jrdAX1EL9R/hDlquSQeb52dt3S4t/jwIqmS+Nh5l56NFUkWQXeg/vu+yUrz4H5FMqbBP+2dPx1bTVum44rzUkdxlG+TwGjYNIg32/XSb3Pc5n9BSZd13zjlnYCJRIc8ehHxjM9cak/UHBG0JHRoMXTQNbtb6Tbxjiknj5Syy7XKn05u8Db9MuZ5ma0CW03okwioqx2jjQdclMDA==","mail-alias-created-date":"1752046281608","From":"Mohamed Mediouni ","To":"qemu-devel@nongnu.org","Cc":"Pedro Barbuda , qemu-arm@nongnu.org,\n Pierrick Bouvier ,\n Mohamed Mediouni ,\n Roman Bolshakov ,\n \"Michael S. Tsirkin\" , Wei Liu ,\n Phil Dennis-Jordan ,\n Peter Maydell , Zhao Liu ,\n Paolo Bonzini ","Subject":"[PATCH v3 14/37] hw/intc: apic: disallow APIC reads when disabled","Date":"Wed, 22 Apr 2026 23:42:02 +0200","Message-ID":"<20260422214225.2242-15-mohamed@unpredictable.fr>","X-Mailer":"git-send-email 2.50.1","In-Reply-To":"<20260422214225.2242-1-mohamed@unpredictable.fr>","References":"<20260422214225.2242-1-mohamed@unpredictable.fr>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Proofpoint-ORIG-GUID":"hQesJzdeXIdUFCn6hT4rmvmdXjO4kuNg","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDIyMDIxMSBTYWx0ZWRfX95RtQ0Ck+aY7\n 0r3hzAc+R7noqmggXUJifgh0hs69C0Yl13m4S04Ag1Ipa4Er6tQhvXoKT1AM/YDsAQZ45w4Hl2M\n /6YrAdRX2sKVkU7ny5I7oa7O8NVQ/NKm/SncHo2wDcbWln7Bd072Q2uSCPJbLMlY6zeLI67WdrM\n 20gLFq5OJk6cLI/8j0aA0hNA/VuX3Zb00YpQ59H2um9XAJRW9nfMxNZmKXXlTCPjkhKmlG9iiJT\n LrC7BOYr0JJFuWrXFJL2qMWjM60a9fb03/iepjzxQIjUXOi9zCoLVL+fYvPgP7oWr71PGhU411k\n 6WFn2B4T1ppu/4cRqVFW/y8kulSuBMkuAg4tmV7dbixq2LoNdVErZ0B+DZR2Vo=","X-Authority-Info-Out":"v=2.4 cv=BpmQAIX5 c=1 sm=1 tr=0 ts=69e940e0\n cx=c_apl:c_pps:t_out a=YrL12D//S6tul8v/L+6tKg==:117\n a=YrL12D//S6tul8v/L+6tKg==:17 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22\n a=JYwUPf56aOQolOdNqfgA:9","X-Proofpoint-GUID":"hQesJzdeXIdUFCn6hT4rmvmdXjO4kuNg","Received-SPF":"pass client-ip=57.103.76.53;\n envelope-from=mohamed@unpredictable.fr; helo=outbound.st.icloud.com","X-Spam_score_int":"-27","X-Spam_score":"-2.8","X-Spam_bar":"--","X-Spam_report":"(-2.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=0.001, SPF_HELO_PASS=-0.001,\n 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":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"!APICBASE_ENABLE + attempting to read xAPIC registers is not an allowed combination.\n\nAnd neither is x2APIC enabled + attempting to read xAPIC registers\n\nSigned-off-by: Mohamed Mediouni \n---\n hw/intc/apic.c | 9 +++++++++\n 1 file changed, 9 insertions(+)","diff":"diff --git a/hw/intc/apic.c b/hw/intc/apic.c\nindex 8766ed00b9..e5ea831261 100644\n--- a/hw/intc/apic.c\n+++ b/hw/intc/apic.c\n@@ -875,6 +875,15 @@ static uint64_t apic_mem_read(void *opaque, hwaddr addr, unsigned size)\n return -1;\n }\n \n+ /* if the xAPIC is disabled, return early. */\n+ if (!(s->apicbase & MSR_IA32_APICBASE_ENABLE)) {\n+ return 0xffffffff;\n+ }\n+\n+ if (is_x2apic_mode(s)) {\n+ return 0xffffffff;\n+ }\n+\n index = (addr >> 4) & 0xff;\n apic_register_read(s, index, &val);\n \n","prefixes":["v3","14/37"]}