From patchwork Thu Feb 9 07:22:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?SsO8cmdlbiBHcm/Dnw==?= X-Patchwork-Id: 13134100 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EAE8DC636D4 for ; Thu, 9 Feb 2023 07:23:00 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.492186.761605 (Exim 4.92) (envelope-from ) id 1pQ1GF-0004XA-Dk; Thu, 09 Feb 2023 07:22:27 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 492186.761605; Thu, 09 Feb 2023 07:22:27 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pQ1GF-0004X3-B7; Thu, 09 Feb 2023 07:22:27 +0000 Received: by outflank-mailman (input) for mailman id 492186; Thu, 09 Feb 2023 07:22:26 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1pQ1GD-0004Wx-Q4 for xen-devel@lists.xenproject.org; Thu, 09 Feb 2023 07:22:25 +0000 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 7f578cfd-a84a-11ed-933c-83870f6b2ba8; Thu, 09 Feb 2023 08:22:23 +0100 (CET) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 3E44220C8B; Thu, 9 Feb 2023 07:22:23 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id B266A1339E; Thu, 9 Feb 2023 07:22:22 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id e00xKi6f5GPgeAAAMHmgww (envelope-from ); Thu, 09 Feb 2023 07:22:22 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 7f578cfd-a84a-11ed-933c-83870f6b2ba8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1675927343; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=QHDr4/oY9jwjgsuyt0ENY6hb99lvK8llTbmW7FwD1WY=; b=hkd/8ZSN2yr1EXH/otlZ2IOhrexNw9ZlHMfSi/2RYl35jCKYc1+CxTPbtthvkyKAMbhsIJ g4kzzt5oIWj2s2vNcLDEo0ZCc5isCqLAHsLy88icLk+t71MwZA7susB62v8ObQjk5OzYP+ PN1MAI+by459aRFgxt6PvL8nvvRR3SU= From: Juergen Gross To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-hyperv@vger.kernel.org Cc: lists@nerdbynature.de, mikelley@microsoft.com, torvalds@linux-foundation.org, Juergen Gross , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , "K. Y. Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Boris Ostrovsky , xen-devel@lists.xenproject.org, Andy Lutomirski , Peter Zijlstra Subject: [PATCH v2 0/8] x86/mtrr: fix handling with PAT but without MTRR Date: Thu, 9 Feb 2023 08:22:12 +0100 Message-Id: <20230209072220.6836-1-jgross@suse.com> X-Mailer: git-send-email 2.35.3 MIME-Version: 1.0 This series tries to fix the rather special case of PAT being available without having MTRRs (either due to CONFIG_MTRR being not set, or because the feature has been disabled e.g. by a hypervisor). The main use cases are Xen PV guests and SEV-SNP guests running under Hyper-V. Instead of trying to work around all the issues by adding if statements here and there, just try to use the complete available infrastructure by setting up a read-only MTRR state when needed. In the Xen PV case the current MTRR MSR values can be read from the hypervisor, while for the SEV-SNP case all needed is to set the default caching mode to "WB". I have added more cleanup which has been discussed when looking into the most recent failures. Note that I couldn't test the Hyper-V related change (patch 3). Running on bare metal and with Xen didn't show any problems with the series applied. Changes in V2: - replaced former patches 1+2 with new patches 1-4, avoiding especially the rather hacky approach of V1, while making all the MTRR type conflict tests available for the Xen PV case - updated patch 6 (was patch 4 in V1) Juergen Gross (8): x86/mtrr: split off physical address size calculation x86/mtrr: support setting MTRR state for software defined MTRRs x86/hyperv: set MTRR state when running as SEV-SNP Hyper-V guest x86/xen: set MTRR state when running as Xen PV initial domain x86/mtrr: revert commit 90b926e68f50 x86/mtrr: don't let mtrr_type_lookup() return MTRR_TYPE_INVALID x86/mm: only check uniform after calling mtrr_type_lookup() x86/mtrr: drop sanity check in mtrr_type_lookup_fixed() arch/x86/include/asm/mtrr.h | 9 +++- arch/x86/include/uapi/asm/mtrr.h | 6 +-- arch/x86/kernel/cpu/mshyperv.c | 8 +++ arch/x86/kernel/cpu/mtrr/generic.c | 56 +++++++++++++++++---- arch/x86/kernel/cpu/mtrr/mtrr.c | 79 ++++++++++++++++-------------- arch/x86/mm/pat/memtype.c | 3 +- arch/x86/mm/pgtable.c | 6 +-- arch/x86/xen/enlighten_pv.c | 49 ++++++++++++++++++ 8 files changed, 159 insertions(+), 57 deletions(-)