From patchwork Thu Nov 2 15:51:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zeng Guang X-Patchwork-Id: 740867 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 9D9B5C4167D for ; Thu, 2 Nov 2023 16:34:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376975AbjKBQeH (ORCPT ); Thu, 2 Nov 2023 12:34:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42022 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347663AbjKBQeF (ORCPT ); Thu, 2 Nov 2023 12:34:05 -0400 Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CE08185; Thu, 2 Nov 2023 09:34:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1698942840; x=1730478840; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=Nbhi+Lxa9AGjvct6KXRPu7ZYORV4sX+cH5+O4Ji6OnI=; b=gbewLks/8QT5Uf9CVVVDqRPSe7I34IZH4YpKdYn8dyn/oguXuNdq2JF+ MvG5DIZxNffE44fgACwdg+2RFLLpdzpJRbmq9bqJiT6MsKAg/6c/J8agv Y4JIKi1gE5N9LJJcRAbpGwwrQimn2SYbyomRCx5sn1bzJvwJ7dD8leuyQ +CXIGIEVnK/iK8bogWzlwSzDrwmeFi7iXzRFfsQJ9FraO0NbqtV2abJ84 nQnTGfCayONpdq+NWleCidIS6/EGbAEShGLun6e0a94/sjp1HULoxWLK+ xmTWs6aA6OcPsJvgQQac5OYp8OPQq9HS1M44dJuDamafg8oXxou9U1Vu4 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10882"; a="388571121" X-IronPort-AV: E=Sophos;i="6.03,272,1694761200"; d="scan'208";a="388571121" Received: from fmviesa001.fm.intel.com ([10.60.135.141]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Nov 2023 09:33:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.03,272,1694761200"; d="scan'208";a="9448555" Received: from arthur-vostro-3668.sh.intel.com ([10.239.159.65]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Nov 2023 09:33:42 -0700 From: Zeng Guang To: Sean Christopherson , Paolo Bonzini , Shuah Khan , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Anup Patel , Atish Patra , David Hildenbrand Cc: kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, Zeng Guang Subject: [RFC PATCH v1 8/8] KVM: selftests: x86: Add KVM forced emulation prefix capability Date: Thu, 2 Nov 2023 23:51:11 +0800 Message-Id: <20231102155111.28821-9-guang.zeng@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20231102155111.28821-1-guang.zeng@intel.com> References: <20231102155111.28821-1-guang.zeng@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Introduce KVM selftest exception fixup using forced emulation prefix to emulate instruction unconditionally when kvm.force_emulation_prefix is enabled. Signed-off-by: Zeng Guang --- .../selftests/kvm/include/x86_64/processor.h | 20 +++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 2534bdf8aa71..a1645508affc 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -1110,6 +1110,10 @@ void vcpu_init_descriptor_tables(struct kvm_vcpu *vcpu); void vm_install_exception_handler(struct kvm_vm *vm, int vector, void (*handler)(struct ex_regs *)); +/* Forced emulation prefix for KVM emulating instruction unconditionally */ +#define KVM_FEP "ud2; .byte 'k', 'v', 'm';" +#define KVM_FEP_LENGTH 5 + /* If a toddler were to say "abracadabra". */ #define KVM_EXCEPTION_MAGIC 0xabacadabaULL @@ -1149,6 +1153,22 @@ void vm_install_exception_handler(struct kvm_vm *vm, int vector, "mov %%r9b, %[vector]\n\t" \ "mov %%r10, %[error_code]\n\t" +/* + * KVM selftest exception fixup using forced emulation prefix enforces KVM + * on emulating instruction unconditionally when kvm.force_emulation_prefix + * is enabled. + */ +#define KVM_FEP_ASM_SAFE(insn) \ + "mov $" __stringify(KVM_EXCEPTION_MAGIC) ", %%r9\n\t" \ + "lea 1f(%%rip), %%r10\n\t" \ + "lea 2f(%%rip), %%r11\n\t" \ + KVM_FEP \ + "1: " insn "\n\t" \ + "xor %%r9, %%r9\n\t" \ + "2:\n\t" \ + "mov %%r9b, %[vector]\n\t" \ + "mov %%r10, %[error_code]\n\t" + #define KVM_ASM_SAFE_OUTPUTS(v, ec) [vector] "=qm"(v), [error_code] "=rm"(ec) #define KVM_ASM_SAFE_CLOBBERS "r9", "r10", "r11"