From patchwork Mon Jul 18 14:11:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Maxim Levitsky X-Patchwork-Id: 12921345 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 3D40CC43334 for ; Mon, 18 Jul 2022 14:11:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235219AbiGROLi (ORCPT ); Mon, 18 Jul 2022 10:11:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36772 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235708AbiGROLh (ORCPT ); Mon, 18 Jul 2022 10:11:37 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 744DA275C1 for ; Mon, 18 Jul 2022 07:11:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658153495; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=Vcb7EQNP7nmt18gfIk7EjblaRPAfBOgB5YIPuamopdk=; b=P6LeF3xy/AR8U+qPK2zn8jA2WE0n/eL430TrlyWfryMyq9BJC5L8fvy9mJYjnikzH8PJma HSX4P+p0fJ4MH6sK4llwSdZc161JFaB9iiPFHom4R5dX1/CPMtJk4heJg0JV+2yNH+P06w SpsfjxTDRVpwO5ZMrRXgIPV5SDyp7kQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-665-HEpFr7HLMUadJh7iEE8vwg-1; Mon, 18 Jul 2022 10:11:32 -0400 X-MC-Unique: HEpFr7HLMUadJh7iEE8vwg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 43E78801231; Mon, 18 Jul 2022 14:11:30 +0000 (UTC) Received: from amdlaptop.tlv.redhat.com (dhcp-4-238.tlv.redhat.com [10.35.4.238]) by smtp.corp.redhat.com (Postfix) with ESMTP id BD78B2026D64; Mon, 18 Jul 2022 14:11:24 +0000 (UTC) From: Maxim Levitsky To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Pawan Gupta , Ingo Molnar , Josh Poimboeuf , Namhyung Kim , Tony Luck , Paolo Bonzini , "H. Peter Anvin" , Arnaldo Carvalho de Melo , Thomas Gleixner , Alexander Shishkin , Tim Chen , Borislav Petkov , "David S. Miller" , Dave Hansen , "Chang S. Bae" , Jane Malalane , Kees Cook , Kan Liang , Peter Zijlstra , Maxim Levitsky , x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)), Herbert Xu , Jiri Olsa , Mark Rutland , linux-perf-users@vger.kernel.org, linux-crypto@vger.kernel.org (open list:CRYPTO API) Subject: [PATCH v2 0/5] x86: cpuid: improve support for broken CPUID configurations Date: Mon, 18 Jul 2022 17:11:18 +0300 Message-Id: <20220718141123.136106-1-mlevitsk@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This patch series aims to harden the cpuid code against the case when the hypervisor exposes a broken CPUID configuration to the guest, in the form of having a feature disabled but not features that depend on it. This is the more generic way to fix kernel panic in aes-ni kernel driver, which was triggered by CPUID configuration in which AVX is disabled but not AVX2. https://lore.kernel.org/all/20211103145231.GA4485@gondor.apana.org.au/T/ This was tested by booting a guest with AVX disabled and not AVX2, and observing that both a warning is now printed in dmesg, and that avx2 is gone from /proc/cpuinfo. V2: I hopefully addressed all the (very good) review feedback. Best regards, Maxim Levitsky Maxim Levitsky (5): perf/x86/intel/lbr: use setup_clear_cpu_cap instead of clear_cpu_cap x86/cpuid: refactor setup_clear_cpu_cap()/clear_cpu_cap() x86/cpuid: move filter_cpuid_features to cpuid-deps.c x86/cpuid: remove 'warn' parameter from filter_cpuid_features x86/cpuid: check for dependencies violations in CPUID and attempt to fix them arch/x86/events/intel/lbr.c | 2 +- arch/x86/include/asm/cpufeature.h | 1 + arch/x86/kernel/cpu/common.c | 51 +------------------- arch/x86/kernel/cpu/cpuid-deps.c | 80 +++++++++++++++++++++++++++---- 4 files changed, 74 insertions(+), 60 deletions(-)