{"id":2225094,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2225094/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260420104248.86702-18-mohamed@unpredictable.fr/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/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":""},"msgid":"<20260420104248.86702-18-mohamed@unpredictable.fr>","date":"2026-04-20T10:42:27","name":"[v2,17/38] whpx: i386: unknown MSR configurability","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"63acdfcd69ab8dce1c8dc33cb86ecfe6bf91f889","submitter":{"id":91318,"url":"http://patchwork.ozlabs.org/api/1.1/people/91318/?format=json","name":"Mohamed Mediouni","email":"mohamed@unpredictable.fr"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260420104248.86702-18-mohamed@unpredictable.fr/mbox/","series":[{"id":500592,"url":"http://patchwork.ozlabs.org/api/1.1/series/500592/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=500592","date":"2026-04-20T10:42:10","name":"WHPX x86 updates for QEMU 11.1","version":2,"mbox":"http://patchwork.ozlabs.org/series/500592/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2225094/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2225094/checks/","tags":{},"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=ZiqMaEhE;\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 4fzhzy6RD4z1yCv\n\tfor ; Mon, 20 Apr 2026 20:48:45 +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 1wEm6T-0007An-7Q; Mon, 20 Apr 2026 06:43:45 -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 1wEm6Q-00079Z-KB\n for qemu-devel@nongnu.org; Mon, 20 Apr 2026 06:43:42 -0400","from p-west3-cluster6-host4-snip4-10.eps.apple.com ([57.103.75.23]\n helo=outbound.ms.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 1wEm6O-0000dj-RV\n for qemu-devel@nongnu.org; Mon, 20 Apr 2026 06:43:42 -0400","from outbound.ms.icloud.com (unknown [127.0.0.2])\n by p00-icloudmta-asmtp-us-west-3a-100-percent-1 (Postfix) with ESMTPS id\n 66B97180045A; Mon, 20 Apr 2026 10:43:36 +0000 (UTC)","from localhost.localdomain (unknown [17.57.154.37])\n by p00-icloudmta-asmtp-us-west-3a-100-percent-1 (Postfix) with ESMTPSA id\n D21F21800478; Mon, 20 Apr 2026 10:43:33 +0000 (UTC)"],"Dkim-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr;\n s=sig1; t=1776681818; x=1779273818;\n bh=6dRDJ5VEmS78xsRk6kMHBpp9Wu7kQoHjBWY816Egd9Q=;\n h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme;\n b=ZiqMaEhERnaCG8BBDaSaBRanydfmEXgOfWTwKXKrYtbhDEoGSzDKpRIjO36TBOG5pPHEJeBws2HhjHjt+uIQQ+pAV6bNFTTP0G1sa3Aw2X1lKur9SFJhx1mfJwSj4RXmi7dZlZDHg9d3/0lTKo686wTVdA7Ml8MjnoPxADNYBbax5A8GyIIVYxMdVwlzQaA3IzKoOsS+035LImh1rQF9R3jNUjUVL0wrv07aTcrMCFeOu/iI/I+HDRqtF0iHkoHNWEoBiPYIEcPYu5AFKrXK1aIAciK1z6M5ialSCxJ3lU5wrt0UbLWHkUX3qAIVHZfCcglFyIUMB/yYgQCuGzb1QQ==","mail-alias-created-date":"1752046281608","From":"Mohamed Mediouni ","To":"qemu-devel@nongnu.org","Cc":"qemu-arm@nongnu.org, Mohamed Mediouni ,\n Paolo Bonzini ,\n Phil Dennis-Jordan ,\n Roman Bolshakov ,\n Pierrick Bouvier ,\n Pedro Barbuda , Wei Liu ,\n \"Michael S. Tsirkin\" ,\n Peter Maydell , Zhao Liu ","Subject":"[PATCH v2 17/38] whpx: i386: unknown MSR configurability","Date":"Mon, 20 Apr 2026 12:42:27 +0200","Message-ID":"<20260420104248.86702-18-mohamed@unpredictable.fr>","X-Mailer":"git-send-email 2.50.1","In-Reply-To":"<20260420104248.86702-1-mohamed@unpredictable.fr>","References":"<20260420104248.86702-1-mohamed@unpredictable.fr>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Proofpoint-GUID":"PDCmDiPyhYelfMhsgCs4mxLsG49E4L6c","X-Authority-Info-Out":"v=2.4 cv=DOGCIiNb c=1 sm=1 tr=0 ts=69e60359\n cx=c_apl:c_pps:t_out a=qkKslKyYc0ctBTeLUVfTFg==:117 a=A5OVakUREuEA:10\n a=VkNPw1HP01LnGYTKEx00:22 a=9z_AL-2ZILZrMqfKHsQA:9","X-Proofpoint-ORIG-GUID":"PDCmDiPyhYelfMhsgCs4mxLsG49E4L6c","X-Proofpoint-Spam-Details-Enc":"AW1haW4tMjYwNDIwMDEwNCBTYWx0ZWRfX9Zq935l7r8mP\n vlaUDFA3GpOv4YI3ojqIp7m3nXUhBecmS38s/+K7J9Cd6QT6Es5ZaRdSsYFWtn4dQKBsUmfUQcx\n N0G4e7MnRvx2W9Zd3L7VHfMzO3o0NHiRcYo+BVtZxvUpCESjNi+79HBuFai56uMpvflSx1BtYy7\n GAqp523lUjnBh3twSWTbsBAnZzZFaf5amr8xtgkUhKbVIy9MhwH4f0lSgExvHj4zqgp6fBwNyvK\n 2RAmkN/sYGD0xd01mtV4lx92WKr0Ip6b6UsngLF7DV9wdG0k4Z0m16XFbgY30iZAPJVJwKgMgVt\n iRpQ+U+M45w73RK6+PWHifpZLCguFPukGyvcZvfu8+tmQKdUaXRJRcMTlk8T1g=","X-Proofpoint-Virus-Version":"vendor=baseguard\n engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49\n definitions=2026-04-20_02,2026-04-17_04,2025-10-01_01","X-Proofpoint-Spam-Details":"rule=notspam policy=default score=0 suspectscore=0\n lowpriorityscore=0 mlxscore=0 spamscore=0\n malwarescore=0 phishscore=0\n adultscore=0 bulkscore=0 mlxlogscore=999 clxscore=1030 classifier=spam\n authscore=0 adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000\n definitions=main-2604200104","Received-SPF":"pass client-ip=57.103.75.23;\n envelope-from=mohamed@unpredictable.fr; helo=outbound.ms.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_H3=0.001, RCVD_IN_MSPIKE_WL=0.001,\n 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":",\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":"Add an option to inject back a GPF for unknown MSRs.\n\nKeep it on by default for now as Linux expects accesses to some\nAMD-specific MSRs to always succeed when on an AMD host.\n\nSigned-off-by: Mohamed Mediouni \n---\n accel/whpx/whpx-common.c | 38 ++++++++++++++++++++++++++++++++++\n include/system/whpx-internal.h | 1 +\n target/i386/whpx/whpx-all.c | 4 ++++\n 3 files changed, 43 insertions(+)","diff":"diff --git a/accel/whpx/whpx-common.c b/accel/whpx/whpx-common.c\nindex 59be996aef..706871f138 100644\n--- a/accel/whpx/whpx-common.c\n+++ b/accel/whpx/whpx-common.c\n@@ -505,6 +505,38 @@ static void whpx_set_hyperv(Object *obj, Visitor *v,\n }\n }\n \n+static void whpx_set_unknown_msr(Object *obj, Visitor *v,\n+ const char *name, void *opaque,\n+ Error **errp)\n+{\n+ struct whpx_state *whpx = &whpx_global;\n+ OnOffAuto mode;\n+\n+ if (!visit_type_OnOffAuto(v, name, &mode, errp)) {\n+ return;\n+ }\n+\n+ switch (mode) {\n+ case ON_OFF_AUTO_ON:\n+ whpx->ignore_unknown_msr = true;\n+ break;\n+\n+ case ON_OFF_AUTO_OFF:\n+ whpx->ignore_unknown_msr = false;\n+ break;\n+\n+ case ON_OFF_AUTO_AUTO:\n+ whpx->ignore_unknown_msr = true;\n+ break;\n+ default:\n+ /*\n+ * The value was checked in visit_type_OnOffAuto() above. If\n+ * we get here, then something is wrong in QEMU.\n+ */\n+ abort();\n+ }\n+}\n+\n static void whpx_cpu_accel_class_init(ObjectClass *oc, const void *data)\n {\n AccelCPUClass *acc = ACCEL_CPU_CLASS(oc);\n@@ -538,6 +570,11 @@ static void whpx_accel_class_init(ObjectClass *oc, const void *data)\n NULL, NULL);\n object_class_property_set_description(oc, \"hyperv\",\n \"Configure Hyper-V enlightenments\");\n+ object_class_property_add(oc, \"ignore-unknown-msr\", \"OnOffAuto\",\n+ NULL, whpx_set_unknown_msr,\n+ NULL, NULL);\n+ object_class_property_set_description(oc, \"ignore-unknown-msr\",\n+ \"Configure unknown MSR behavior\");\n }\n \n static void whpx_accel_instance_init(Object *obj)\n@@ -552,6 +589,7 @@ static void whpx_accel_instance_init(Object *obj)\n whpx->hyperv_enlightenments_required = false;\n /* Value determined at whpx_accel_init */\n whpx->hyperv_enlightenments_enabled = false;\n+ whpx->ignore_unknown_msr = true;\n }\n \n static const TypeInfo whpx_accel_type = {\ndiff --git a/include/system/whpx-internal.h b/include/system/whpx-internal.h\nindex cf782cf5f8..86639627b3 100644\n--- a/include/system/whpx-internal.h\n+++ b/include/system/whpx-internal.h\n@@ -47,6 +47,7 @@ struct whpx_state {\n bool hyperv_enlightenments_required;\n bool hyperv_enlightenments_enabled;\n \n+ bool ignore_unknown_msr;\n };\n \n extern struct whpx_state whpx_global;\ndiff --git a/target/i386/whpx/whpx-all.c b/target/i386/whpx/whpx-all.c\nindex 0d72e93621..550f30d50a 100644\n--- a/target/i386/whpx/whpx-all.c\n+++ b/target/i386/whpx/whpx-all.c\n@@ -2048,6 +2048,10 @@ int whpx_vcpu_run(CPUState *cpu)\n vcpu->exit_ctx.MsrAccess.AccessInfo.IsWrite);\n }\n \n+ if (!is_known_msr && !whpx->ignore_unknown_msr) {\n+ x86_emul_raise_exception(&X86_CPU(cpu)->env, EXCP0D_GPF, 0);\n+ }\n+\n hr = whp_dispatch.WHvSetVirtualProcessorRegisters(\n whpx->partition,\n cpu->cpu_index,\n","prefixes":["v2","17/38"]}