From patchwork Wed Dec 28 19:24:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vishal Annapurve X-Patchwork-Id: 13083162 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 18130C4332F for ; Wed, 28 Dec 2022 19:25:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233451AbiL1TZX (ORCPT ); Wed, 28 Dec 2022 14:25:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233446AbiL1TZF (ORCPT ); Wed, 28 Dec 2022 14:25:05 -0500 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E48CE186A3 for ; Wed, 28 Dec 2022 11:24:56 -0800 (PST) Received: by mail-pl1-x64a.google.com with SMTP id m16-20020a170902db1000b0018fa0de6aa6so12581757plx.18 for ; Wed, 28 Dec 2022 11:24:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=sIyfuO6L8HnU8CmCldKrIpDi7aTZJyxJfn1wljTzIeI=; b=HbphtqtIjGcu1bCKK6wFWu4E/GlYZGDlsYger0IgbCeUkoHRrvjgvwYnY/vOQNJS3v FyjI7bdMglfCpRTTsNvK49p8IyLNoVRBVdcnldRVB+HUTo08LKiSrhC5Q/0Uc+QQdp+X IHJ89MTp65CrwucYaVMtjMiROhNdBnnGYlBREUmDHiQkTkehUA4DlpRUBvud1+SVqpMC 6jKDiAXw31yGNOiO07z1YlMzIXbFVC8qVLvnQMkUpOleAVc5L3CryHcplcqTmY4Pt+Gf tXjGKaI88IH6T+SOZw737PpHr745DcyWzXyYFxhUqfzzIygXPYuztcWMdNooU6ZBsvBQ U5Yg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=sIyfuO6L8HnU8CmCldKrIpDi7aTZJyxJfn1wljTzIeI=; b=rKxCpf2iHyMPw9Vo5gHSQgpT0383SADizV4ZNNr4K6jl1c2CL49fDdxQlmxoyYqvUK A5QnVZvJ6I3RY2jAXe+aaBsZe3QvIDvLRJTJiVXRGFjRjQY9sInVMmzLvZml3s0aIVj5 QLESg85hoFKOutIRziHuWu92n00gnvXnBQX9f8MlmGwTm3r0Oclnmi1eAPJKaGE2S3gT 0r9cXemzr2FCYgoSbf5sKkRwPoIgBV5DDyLqkVCWKMdb4Y5nsC81jwsTkEyn/PSdQcKW N91dNMvvZfJWWjdJqAbBnrSc6OVd0sGB1eOHe/Wbwtejb/dpZTrt2aCG83noIFE59tXf ZRHw== X-Gm-Message-State: AFqh2kpaUNJ0+OMjXo5MuGqDsFvZxpdEzOdXZs5ZAhKsShibDNJPiaLu KkbpsBeVGg9y4eqnPFc1UhI3X8nvGTutZyBi X-Google-Smtp-Source: AMrXdXvOH+6kWmrNXWr4DzT0DiqLcTz70aEBBsdc901akacOkyNgSBf4mYJaruRIUQ+DNlIh+bmPNeoAoGZ2Pser X-Received: from vannapurve2.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:41f8]) (user=vannapurve job=sendgmr) by 2002:a17:90a:7c48:b0:225:ff38:5494 with SMTP id e8-20020a17090a7c4800b00225ff385494mr796035pjl.151.1672255496443; Wed, 28 Dec 2022 11:24:56 -0800 (PST) Date: Wed, 28 Dec 2022 19:24:38 +0000 In-Reply-To: <20221228192438.2835203-1-vannapurve@google.com> Mime-Version: 1.0 References: <20221228192438.2835203-1-vannapurve@google.com> X-Mailer: git-send-email 2.39.0.314.g84b9a713c41-goog Message-ID: <20221228192438.2835203-5-vannapurve@google.com> Subject: [V4 PATCH 4/4] KVM: selftests: x86: Invoke kvm hypercall as per host cpu From: Vishal Annapurve To: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: pbonzini@redhat.com, shuah@kernel.org, bgardon@google.com, seanjc@google.com, oupton@google.com, peterx@redhat.com, vkuznets@redhat.com, dmatlack@google.com, Vishal Annapurve Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Invoke vmcall/vmmcall instructions from kvm_hypercall as per host CPU type. CVMs and current kvm_hyerpcall callers need to execute hypercall as per the cpu type to avoid KVM having to emulate the instruction anyways. CVMs need to avoid KVM emulation as the guest code is not updatable from KVM. Guest code region can be marked un-mondifiable from KVM without CVMs as well, so in general it's safer to avoid KVM emulation for vmcall/vmmcall instructions. Suggested-by: Sean Christopherson Signed-off-by: Vishal Annapurve --- tools/testing/selftests/kvm/lib/x86_64/processor.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c index 18f0608743d1..cc0b9c17fa91 100644 --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c @@ -1154,9 +1154,15 @@ uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2, { uint64_t r; - asm volatile("vmcall" + asm volatile("test %[use_vmmcall], %[use_vmmcall]\n\t" + "jnz 1f\n\t" + "vmcall\n\t" + "jmp 2f\n\t" + "1: vmmcall\n\t" + "2:" : "=a"(r) - : "a"(nr), "b"(a0), "c"(a1), "d"(a2), "S"(a3)); + : "a"(nr), "b"(a0), "c"(a1), "d"(a2), "S"(a3), + [use_vmmcall] "r" (is_host_cpu_amd())); return r; }