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: 637504 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 C7381C4332F for ; Wed, 28 Dec 2022 19:25:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233582AbiL1TZS (ORCPT ); Wed, 28 Dec 2022 14:25:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46316 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232983AbiL1TZF (ORCPT ); Wed, 28 Dec 2022 14:25:05 -0500 Received: from mail-pj1-x1049.google.com (mail-pj1-x1049.google.com [IPv6:2607:f8b0:4864:20::1049]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD4181705E for ; Wed, 28 Dec 2022 11:24:56 -0800 (PST) Received: by mail-pj1-x1049.google.com with SMTP id r17-20020a17090aa09100b0021903e75f14so7090335pjp.9 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=MnqUbjBH5ZtEuiYBl7flzcHTKlbmPX8qehPnymH5Tej/0sgPMg68TwIFhAls5BZ6HO A4hUMkTWey4G3H3cFEOHE9lN3g8PyYPMrz2DgT8g67N9IkeS58COrViw37wmNBYRlh7p vrDg2QYS+UQxq00/ImVy1fhwPee173thyGwExywmZr4u4hXoBSJj8iW4iw8qk1Ke7Xec Gi43RsmR+jAIC76eeNTVP6WvdpxFO740oIEZYqCY2x3jXGscXQmmA1znfS18HjQT8usu Cof9OVGJgcTe6vVJ4uykWeprcTLOmiBxx19e27PkICWSDhzIWW+B30FOTkRUC1uuYvZQ pPDQ== X-Gm-Message-State: AFqh2krVI7I1m59aKkDDLGEXxKpPSOEmC5LXMfMFAUV8lkZ70Talle7g IEkMeq/WyiiH0smEAM2rMvqqCYumrQbP6P1l 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: linux-kselftest@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; }