{"id":2226930,"url":"http://patchwork.ozlabs.org/api/patches/2226930/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260422214225.2242-37-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":"<20260422214225.2242-37-mohamed@unpredictable.fr>","list_archive_url":null,"date":"2026-04-22T21:42:24","name":"[v3,36/37] whpx: i386: add SeparateSecurityDomain flag and make default","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"9efd764948953882ad3d6ad2e967c8014298d067","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/20260422214225.2242-37-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/2226930/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2226930/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=gcjJEN+8;\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 4g1CSx1pxdz1yHy\n\tfor ; Thu, 23 Apr 2026 07:45:37 +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 1wFfMP-0000YX-2I; Wed, 22 Apr 2026 17:43:53 -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 1wFfMK-0000ID-Qr\n for qemu-devel@nongnu.org; Wed, 22 Apr 2026 17:43:48 -0400","from p-east2-cluster5-host1-snip4-10.eps.apple.com ([57.103.79.13]\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 1wFfMI-0007uH-7K\n for qemu-devel@nongnu.org; Wed, 22 Apr 2026 17:43:48 -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 33EAC1800235; Wed, 22 Apr 2026 21:43:40 +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 28FDF180023C; Wed, 22 Apr 2026 21:43:35 +0000 (UTC)"],"X-ICL-Out-Info":"\n HUtFAUMHWwJACUgBTUQeDx5WFlZNRAJCTQFIHV8DWRxBAUkdXw9LVxQEFVwFVgZXFHkNXR1FDlYZWgxSD1sOHBZLWFUJCgZdGFgVVgl3HlwASx1XBFQfUxJVHR0LRUtAEwRJAU1fDl4fBBdGGVUERx5dVkAZGQJRHFYNV0NUBF9QSQxBUGxaAEcXSB1dGVlvUF0cDhhZG0AVXRFQGVYJXhUXHkFNWgJWTQVKA18BWwZCC0oCWQVZB14LSgdfGlgFXVQXWwxaDlYwTBZDH1IPWxNNGVEBUkVUAgdYRxRHDg8TTAtHAlo0Vh9UGVoD","Dkim-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=unpredictable.fr;\n s=sig1; t=1776894225; x=1779486225;\n bh=C5WRRvURtBayyBiG835j2KXKO2FgKSgzzKn5mAraQ9M=;\n h=From:To:Subject:Date:Message-ID:MIME-Version:x-icloud-hme;\n b=gcjJEN+8NuwFKU7XcWiq5Nm+z5321MM2VMrr+LKzCHhTUYu6HdcWtlS0sTh0eo3Nm7E+idcNr2a2wd7RyMGTO00YDvd8gEWuV2XkPFUNN2k/emhmHdhrYDIO/kNYEAcE0hAoCAMpy4Itfi/BGq9ZAHyZLvmVe+uM1S+KfQB275iDbu7iGSeY23WSFfo3wHp2iJXdp3lm6d/q9dX6bIE0Lf3CWrQ88mpwS8C+Stf3rg22qU2aF3rqRgFWKQE/VsmlyX8tRylTDp2L0iRjCU828D0xw3Ammk8ZGeHNJcbgL6+bAYJEb6RSX3ztxZwzHJGf3d39AUFDr8g7u6GZObvy1w==","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 36/37] whpx: i386: add SeparateSecurityDomain flag and make\n default","Date":"Wed, 22 Apr 2026 23:42:24 +0200","Message-ID":"<20260422214225.2242-37-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-Spam-Details-Enc":"AW1haW4tMjYwNDIyMDIxMiBTYWx0ZWRfX9oTjBs4MnP3V\n VXfgh++ldqwJunPdVg05KdaNjofSaSc4ZGdrAbGb099el/30DS2enICL2tZQtGo5apL0v+n9weB\n oNDLZCyGOpFpONQXfpvTsw2/1zShQrXezecSw48nIQ4GfMQyxMaZProXbigU4c/qsgSRzacIOfa\n PVaZJbTpHR5HQSj9QoZY2ZmVta8Cnjh3tqSqrWcIvwlioNqXx+vxiKG/k5ytP4mL5bPDhaPNIml\n Bk+AT4ofo6XHmnhvOiu5GkH0ajnMTNW9sKYYaTv4Ths9pFHDxZuEtQpyDrB1N89fPknquufNAbg\n 7h3dKiEuNVK3alo6glLyz96sh4HEdZlhKOwrCHD9OVCFBXpTzEdGfkRHA/F9Mw=","X-Proofpoint-GUID":"r-kcIHqkpANMylvvMitAtNLeP4rw2eCh","X-Authority-Info-Out":"v=2.4 cv=Uplu9uwB c=1 sm=1 tr=0 ts=69e9410f\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=sJaswNuOvxcMbF25v3wA:9","X-Proofpoint-ORIG-GUID":"r-kcIHqkpANMylvvMitAtNLeP4rw2eCh","Received-SPF":"pass client-ip=57.103.79.13;\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=unavailable 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":"For workloads where isolation is less important, -accel whpx,ssd=off\nwill provide significantly higher MMIO performance.\n\nSigned-off-by: Mohamed Mediouni \n---\n accel/whpx/whpx-common.c | 1 +\n include/system/whpx-internal.h | 1 +\n target/i386/whpx/whpx-all.c | 63 ++++++++++++++++++++++++++++++++++\n 3 files changed, 65 insertions(+)","diff":"diff --git a/accel/whpx/whpx-common.c b/accel/whpx/whpx-common.c\nindex 305b2ae1d0..e5dabb6bdf 100644\n--- a/accel/whpx/whpx-common.c\n+++ b/accel/whpx/whpx-common.c\n@@ -557,6 +557,7 @@ static void whpx_accel_instance_init(Object *obj)\n whpx->ignore_unknown_msr = true;\n whpx->intercept_msr_gp = false;\n whpx->nested_virt_enabled = true;\n+ whpx->separate_security_domain = 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 4436cfe6ba..08a49706ff 100644\n--- a/include/system/whpx-internal.h\n+++ b/include/system/whpx-internal.h\n@@ -48,6 +48,7 @@ struct whpx_state {\n bool hyperv_enlightenments_enabled;\n \n bool nested_virt_enabled;\n+ bool separate_security_domain;\n \n bool ignore_unknown_msr;\n bool intercept_msr_gp;\ndiff --git a/target/i386/whpx/whpx-all.c b/target/i386/whpx/whpx-all.c\nindex d17db73cff..035a8231b7 100644\n--- a/target/i386/whpx/whpx-all.c\n+++ b/target/i386/whpx/whpx-all.c\n@@ -3006,6 +3006,38 @@ static void whpx_set_nested_virt(Object *obj, Visitor *v,\n }\n }\n \n+static void whpx_set_ssd(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->separate_security_domain = true;\n+ break;\n+\n+ case ON_OFF_AUTO_OFF:\n+ whpx->separate_security_domain = false;\n+ break;\n+\n+ case ON_OFF_AUTO_AUTO:\n+ whpx->separate_security_domain = 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 \n void whpx_arch_accel_class_init(ObjectClass *oc)\n {\n@@ -3024,6 +3056,11 @@ void whpx_arch_accel_class_init(ObjectClass *oc)\n NULL, NULL);\n object_class_property_set_description(oc, \"intercept-msr-gp\",\n \"Toggle nested virtualization off/on.\");\n+ object_class_property_add(oc, \"ssd\", \"OnOffAuto\",\n+ NULL, whpx_set_ssd,\n+ NULL, NULL);\n+ object_class_property_set_description(oc, \"ssd\",\n+ \"Separate security domain\");\n }\n \n int whpx_accel_init(AccelState *as, MachineState *ms)\n@@ -3223,6 +3260,32 @@ int whpx_accel_init(AccelState *as, MachineState *ms)\n info_report(\"WHPX: nested virtualisation not available\");\n }\n \n+ /*\n+ * The combination of separate security domain off\n+ * and disabling specifically these features results\n+ * in a significant vmexit performance improvement\n+ * by skipping speculative execution mitigations.\n+ */\n+ if (!whpx->separate_security_domain) {\n+ processor_features.Bank0.IbrsSupport = 0;\n+ processor_features.Bank0.StibpSupport = 0;\n+ processor_features.Bank0.IbpbSupport = 0;\n+ processor_features.Bank0.SsbdSupport = 0;\n+ processor_features.Bank0.IbrsAllSupport = 0;\n+ processor_features.Bank1.PsfdSupport = 0;\n+ memset(&prop, 0, sizeof(WHV_PARTITION_PROPERTY));\n+ prop.SeparateSecurityDomain = 0;\n+ hr = whp_dispatch.WHvSetPartitionProperty(\n+ whpx->partition,\n+ WHvPartitionPropertyCodeSeparateSecurityDomain,\n+ &prop,\n+ sizeof(WHV_PARTITION_PROPERTY));\n+ if (FAILED(hr)) {\n+ error_report(\"WHPX: failed to unset separate security domain, hr=%08lx\", hr);\n+ /* Some old Windows 10 releases didn't have this, so not fatal*/\n+ }\n+ }\n+\n hr = whp_dispatch.WHvSetPartitionProperty(\n whpx->partition,\n WHvPartitionPropertyCodeProcessorFeaturesBanks,\n","prefixes":["v3","36/37"]}