From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AEC92C2D0E7 for ; Fri, 27 Mar 2020 03:03:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 71E80208E0 for ; Fri, 27 Mar 2020 03:03:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585278185; bh=b2ccDeO/pD0R+Y+srohROcyVA9Q145YuMgSh8oAXLmM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=QO2hVGsaJ/6BHfu6WN1Ir0hObZ9gPwwBsOPmpOXyDpXBixE2Gq1hA55uXmuEWcQfB m5wCvZRf9euI+/KEAX0pjwbm639W+BXQQXpRUoE8sZwTw6h5GC2gP12Tq1GIzBuiDV QC6UfRRcFEPGSbpL1XuferEpLhnteyo77TeCPYdo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727820AbgC0DDC (ORCPT ); Thu, 26 Mar 2020 23:03:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:42064 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726496AbgC0DDC (ORCPT ); Thu, 26 Mar 2020 23:03:02 -0400 Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4CA9C20787; Fri, 27 Mar 2020 03:02:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585278181; bh=b2ccDeO/pD0R+Y+srohROcyVA9Q145YuMgSh8oAXLmM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=rniJm74HvN/lsrQkGt9EY0ampwZGukQI1mGNUHZ+Y1qgVosyqSmxQh7Y/aB0kiHUd skjYGOhr0dmRm2/Rkd2IbLKBHC5ii1/ZdoWPnM2LYGCid8jJUA+iigEapBxQLUIJVy je1LuCvKfE6zYULbGOvvJ9u/UCVNUeI2v0ouqBgk= Date: Fri, 27 Mar 2020 12:02:32 +0900 From: Masami Hiramatsu To: Borislav Petkov , Joerg Roedel Cc: Joerg Roedel , x86@kernel.org, hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Hellstrom , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, Joerg Roedel , Masami Hiramatsu Subject: Re: [PATCH 05/70] x86/insn: Make inat-tables.c suitable for pre-decompression code Message-Id: <20200327120232.c8e455ca100dc0d96e4ddc43@kernel.org> In-Reply-To: <20200325153945.GD27261@zn.tnic> References: <20200319091407.1481-1-joro@8bytes.org> <20200319091407.1481-6-joro@8bytes.org> <20200325153945.GD27261@zn.tnic> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi, On Wed, 25 Mar 2020 16:39:45 +0100 Borislav Petkov wrote: > + Masami. > > On Thu, Mar 19, 2020 at 10:13:02AM +0100, Joerg Roedel wrote: > > From: Joerg Roedel > > > > The inat-tables.c file has some arrays in it that contain pointers to > > other arrays. These pointers need to be relocated when the kernel > > image is moved to a different location. > > > > The pre-decompression boot-code has no support for applying ELF > > relocations, so initialize these arrays at runtime in the > > pre-decompression code to make sure all pointers are correctly > > initialized. I need to check the whole series, but as far as I can understand from this patch, this seems not allowing to store the address value in static pointers. It may break more things, for example _kprobe_blacklist records the NOKPROBE_SYMBOL() symbol addresses at the build time. I have some comments here. > > Signed-off-by: Joerg Roedel > > --- > > arch/x86/tools/gen-insn-attr-x86.awk | 50 +++++++++++++++++++++- > > tools/arch/x86/tools/gen-insn-attr-x86.awk | 50 +++++++++++++++++++++- > > 2 files changed, 98 insertions(+), 2 deletions(-) > > > > diff --git a/arch/x86/tools/gen-insn-attr-x86.awk b/arch/x86/tools/gen-insn-attr-x86.awk > > index a42015b305f4..af38469afd14 100644 > > --- a/arch/x86/tools/gen-insn-attr-x86.awk > > +++ b/arch/x86/tools/gen-insn-attr-x86.awk > > @@ -362,6 +362,9 @@ function convert_operands(count,opnd, i,j,imm,mod) > > END { > > if (awkchecked != "") > > exit 1 > > + > > + print "#ifndef __BOOT_COMPRESSED\n" > > + > > # print escape opcode map's array > > print "/* Escape opcode map array */" > > print "const insn_attr_t * const inat_escape_tables[INAT_ESC_MAX + 1]" \ > > @@ -388,6 +391,51 @@ END { > > for (j = 0; j < max_lprefix; j++) > > if (atable[i,j]) > > print " ["i"]["j"] = "atable[i,j]"," > > - print "};" > > + print "};\n" > > + > > + print "#else /* !__BOOT_COMPRESSED */\n" I think the definitions of inat_*_tables can be shared in both case. If __BOOT_COMPRESSED is set, we can define inat_init_tables() as a initialize function, and if not, it will be just a dummy "do {} while (0)". BTW, where is the __BOOT_COMPRESSED defined? > > + > > + print "/* Escape opcode map array */" > > + print "static const insn_attr_t *inat_escape_tables[INAT_ESC_MAX + 1]" \ > > + "[INAT_LSTPFX_MAX + 1];" > > + print "" > > + > > + print "/* Group opcode map array */" > > + print "static const insn_attr_t *inat_group_tables[INAT_GRP_MAX + 1]"\ > > + "[INAT_LSTPFX_MAX + 1];" > > + print "" > > + > > + print "/* AVX opcode map array */" > > + print "static const insn_attr_t *inat_avx_tables[X86_VEX_M_MAX + 1]"\ > > + "[INAT_LSTPFX_MAX + 1];" > > + print "" > > + > > + print "static void inat_init_tables(void)" This functions should be "inline". And I can not see the call-site of inat_init_tables() in this patch. If possible, please include call-site with definition (especially new init function) so that I can check the init call timing too. > > + print "{" > > + > > + # print escape opcode map's array > > + print "\t/* Print Escape opcode map array */" > > + for (i = 0; i < geid; i++) > > + for (j = 0; j < max_lprefix; j++) > > + if (etable[i,j]) > > + print "\tinat_escape_tables["i"]["j"] = "etable[i,j]";" > > + print "" > > + > > + # print group opcode map's array > > + print "\t/* Print Group opcode map array */" > > + for (i = 0; i < ggid; i++) > > + for (j = 0; j < max_lprefix; j++) > > + if (gtable[i,j]) > > + print "\tinat_group_tables["i"]["j"] = "gtable[i,j]";" > > + print "" > > + # print AVX opcode map's array > > + print "\t/* Print AVX opcode map array */" > > + for (i = 0; i < gaid; i++) > > + for (j = 0; j < max_lprefix; j++) > > + if (atable[i,j]) > > + print "\tinat_avx_tables["i"]["j"] = "atable[i,j]";" > > + > > + print "}" > > + print "#endif" > > } The code itself looks good to me. Thank you, -- Masami Hiramatsu