{"id":2223164,"url":"http://patchwork.ozlabs.org/api/patches/2223164/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260414155433.483186-7-magnuskulke@linux.microsoft.com/","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":"<20260414155433.483186-7-magnuskulke@linux.microsoft.com>","list_archive_url":null,"date":"2026-04-14T15:54:30","name":"[v4,6/9] target/i386: query mshv accel for supported cpuids","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"0f24f1117ecfc47cfa12c9b977c04f48fad8bb87","submitter":{"id":90753,"url":"http://patchwork.ozlabs.org/api/people/90753/?format=json","name":"Magnus Kulke","email":"magnuskulke@linux.microsoft.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260414155433.483186-7-magnuskulke@linux.microsoft.com/mbox/","series":[{"id":499862,"url":"http://patchwork.ozlabs.org/api/series/499862/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=499862","date":"2026-04-14T15:54:24","name":"Support QEMU cpu models in MSHV accelerator","version":4,"mbox":"http://patchwork.ozlabs.org/series/499862/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2223164/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2223164/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 (1024-bit key;\n unprotected) header.d=linux.microsoft.com header.i=@linux.microsoft.com\n header.a=rsa-sha256 header.s=default header.b=iMKe5yIw;\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 4fw8500CMmz1xtJ\n\tfor ; Wed, 15 Apr 2026 01:55:48 +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 1wCg6L-0004bc-Ax; Tue, 14 Apr 2026 11:54:57 -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 1wCg6K-0004Yi-22\n for qemu-devel@nongnu.org; Tue, 14 Apr 2026 11:54:56 -0400","from linux.microsoft.com ([13.77.154.182])\n by eggs.gnu.org with esmtp (Exim 4.90_1)\n (envelope-from ) id 1wCg6I-0000GZ-2O\n for qemu-devel@nongnu.org; Tue, 14 Apr 2026 11:54:55 -0400","from DESKTOP-TUU1E5L.localdomain (unknown [167.220.208.32])\n by linux.microsoft.com (Postfix) with ESMTPSA id 9B02220B6F08;\n Tue, 14 Apr 2026 08:54:51 -0700 (PDT)"],"DKIM-Filter":"OpenDKIM Filter v2.11.0 linux.microsoft.com 9B02220B6F08","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com;\n s=default; t=1776182093;\n bh=d9/BQeP8wUYO1IyE343ZkHR9ZgOOFZiIbPXo9Fv94yA=;\n h=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n b=iMKe5yIw4qsQG7p8OpJfrUCoChfcCF1L+4W9ZiGFoKtTx3sGFMClvEx3EyrqJgG8I\n NbBZDWwWZsG9xJfSFqB1XDU04t3wRnAB922O6efNvWf8MKRWJeYvQOcQ979E9QpR3I\n 8Sl0N4PHFOqbl7Q9RvOzrqv/iovCaWi1imqE1U9o=","From":"Magnus Kulke ","To":"qemu-devel@nongnu.org","Cc":"Wei Liu , Wei Liu ,\n Magnus Kulke ,\n Magnus Kulke , Zhao Liu ,\n Paolo Bonzini ","Subject":"[PATCH v4 6/9] target/i386: query mshv accel for supported cpuids","Date":"Tue, 14 Apr 2026 17:54:30 +0200","Message-Id":"<20260414155433.483186-7-magnuskulke@linux.microsoft.com>","X-Mailer":"git-send-email 2.34.1","In-Reply-To":"<20260414155433.483186-1-magnuskulke@linux.microsoft.com>","References":"<20260414155433.483186-1-magnuskulke@linux.microsoft.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","Received-SPF":"pass client-ip=13.77.154.182;\n envelope-from=magnuskulke@linux.microsoft.com; helo=linux.microsoft.com","X-Spam_score_int":"-42","X-Spam_score":"-4.3","X-Spam_bar":"----","X-Spam_report":"(-4.3 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1,\n DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, RCVD_IN_DNSWL_MED=-2.3,\n RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=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":"We implement mshv_get_supported_cpuid() and invoke it in\nx86_cpu_get_supported_feature_word() retrieve the cpu features that the\nhost is supporting. Initially we mask the virtualization capabilitities\npotentially we might need to mask more in the future.\n\nSigned-off-by: Magnus Kulke \n---\n include/system/mshv.h | 3 +++\n target/i386/cpu.c | 8 ++++++++\n target/i386/mshv/mshv-cpu.c | 27 +++++++++++++++++++++++++++\n 3 files changed, 38 insertions(+)","diff":"diff --git a/include/system/mshv.h b/include/system/mshv.h\nindex 75286baf16..51b0420735 100644\n--- a/include/system/mshv.h\n+++ b/include/system/mshv.h\n@@ -60,4 +60,7 @@ int mshv_irqchip_add_irqfd_notifier_gsi(const EventNotifier *n,\n const EventNotifier *rn, int virq);\n int mshv_irqchip_remove_irqfd_notifier_gsi(const EventNotifier *n, int virq);\n \n+/* cpuid */\n+uint32_t mshv_get_supported_cpuid(uint32_t func, uint32_t idx, int reg);\n+\n #endif\ndiff --git a/target/i386/cpu.c b/target/i386/cpu.c\nindex c6fd1dc00e..4dd9752fd0 100644\n--- a/target/i386/cpu.c\n+++ b/target/i386/cpu.c\n@@ -26,6 +26,7 @@\n #include \"tcg/helper-tcg.h\"\n #include \"exec/translation-block.h\"\n #include \"system/hvf.h\"\n+#include \"system/mshv.h\"\n #include \"hvf/hvf-i386.h\"\n #include \"kvm/kvm_i386.h\"\n #include \"kvm/tdx.h\"\n@@ -8087,6 +8088,13 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu, FeatureWord w)\n r = hvf_get_supported_cpuid(wi->cpuid.eax,\n wi->cpuid.ecx,\n wi->cpuid.reg);\n+ } else if (mshv_enabled()) {\n+ if (wi->type != CPUID_FEATURE_WORD) {\n+ return 0;\n+ }\n+ r = mshv_get_supported_cpuid(wi->cpuid.eax,\n+ wi->cpuid.ecx,\n+ wi->cpuid.reg);\n } else if (tcg_enabled() || qtest_enabled()) {\n r = wi->tcg_features;\n } else {\ndiff --git a/target/i386/mshv/mshv-cpu.c b/target/i386/mshv/mshv-cpu.c\nindex 09878ef357..3b392533b4 100644\n--- a/target/i386/mshv/mshv-cpu.c\n+++ b/target/i386/mshv/mshv-cpu.c\n@@ -1639,6 +1639,33 @@ void mshv_arch_destroy_vcpu(CPUState *cpu)\n g_clear_pointer(&env->emu_mmio_buf, g_free);\n }\n \n+uint32_t mshv_get_supported_cpuid(uint32_t func, uint32_t idx, int reg)\n+{\n+ uint32_t eax, ebx, ecx, edx;\n+ uint32_t ret = 0;\n+\n+ host_cpuid(func, idx, &eax, &ebx, &ecx, &edx);\n+ switch (reg) {\n+ case R_EAX:\n+ ret = eax; break;\n+ case R_EBX:\n+ ret = ebx; break;\n+ case R_ECX:\n+ ret = ecx; break;\n+ case R_EDX:\n+ ret = edx; break;\n+ }\n+\n+ /* Disable nested virtualization features not yet supported by MSHV */\n+ if (func == 0x80000001 && reg == R_ECX) {\n+ ret &= ~CPUID_EXT3_SVM;\n+ }\n+ if (func == 0x01 && reg == R_ECX) {\n+ ret &= ~CPUID_EXT_VMX;\n+ }\n+ return ret;\n+}\n+\n /*\n * Default Microsoft Hypervisor behavior for unimplemented MSR is to send a\n * fault to the guest if it tries to access it. It is possible to override\n","prefixes":["v4","6/9"]}