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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham 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 B8815C2BD09 for ; Fri, 6 Dec 2019 22:14:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 85F4524670 for ; Fri, 6 Dec 2019 22:14:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Sql0AUQx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726490AbfLFWOA (ORCPT ); Fri, 6 Dec 2019 17:14:00 -0500 Received: from mail-pj1-f73.google.com ([209.85.216.73]:48946 "EHLO mail-pj1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726374AbfLFWN7 (ORCPT ); Fri, 6 Dec 2019 17:13:59 -0500 Received: by mail-pj1-f73.google.com with SMTP id o34so4331131pjb.15 for ; Fri, 06 Dec 2019 14:13:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Y+PZLTAB8cI7c6J3sLNCtDVk2nPLg4lB7Nz2OXbvgbI=; b=Sql0AUQx2FX2+C0fZujtdRKnpRimsqUsMS37x70l9M+sOZFbVJ3hWRwdsyDW5ACQD3 mAFiXZYiLY1AxLu49KVGTXlXxNh1yY51dVbs0fY+4RxUcDmlWjM22YiWJSg/QlijLlR+ LISSq0wh25qYppp+BCGBB3ASJ1IgdITLPyf57W++PmDhiZDO9WUYAB9cU3+NXaPjqcDE w4CLiFmNqW2XUK+Aroyl+dGcmQuxGGKW5WDjVx7vwC4+K9oGr9pTR8aiSWYEsabN9s4Z of4oOaIcSsRqcB6G4NGSbYRdfgN3Yi0kLtEC7/W0nA3ypJZva+dNrCITv6RcezBKGZVX zaWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Y+PZLTAB8cI7c6J3sLNCtDVk2nPLg4lB7Nz2OXbvgbI=; b=daBNxMDOzU6fxJQstq+yZ5eB4sF2qof5KM9hxVPQzsNBqcBvev0+y93r150I1FLdhG DcDfcmr1aGjpKThhzQNBwUt1Oho2GeoR61Pa1gqOzYlZU9rpPnUA6dt9WVE5NdsI7wq5 Wh7Ek4a1Z9DAwokLjSJrXF14x8t4A+MhIky5nY8Y/RbfGhq+njEh5R+uKXCS5WXGqblM MRq3O46pxT3g8gctCn6Z2enYLS9ERrsRWQCxzVX5Y+dwfhjdEU6t73bIsed/zWlO9JKL qPypx6ko3xYWtNC10t33ImESkXC7AKiPiOqEEwKiloecCaqSYfPBvvlmZdFaWXvlKPOK k+MA== X-Gm-Message-State: APjAAAVwmtPCTgz8VGnL4sSFgnyCqGFE1Q2UT1HwGQcibM9NEepyLpkc 5pobnXNDz+LaUmrFd0tHhE09yuoyE8RAhq+WiNE= X-Google-Smtp-Source: APXvYqywVZLwuqAoGiiDNrG08v6/3uqPLMW0Y7Sv/F1SLZBSFv5TaL7pDBX3rz4+Y7se97Kpozoy9je2n3q8Y+FKxcA= X-Received: by 2002:a63:de4a:: with SMTP id y10mr5991658pgi.367.1575670438461; Fri, 06 Dec 2019 14:13:58 -0800 (PST) Date: Fri, 6 Dec 2019 14:13:37 -0800 In-Reply-To: <20191206221351.38241-1-samitolvanen@google.com> Message-Id: <20191206221351.38241-2-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191206221351.38241-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.393.g34dc348eaf-goog Subject: [PATCH v6 01/15] arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland Cc: Dave Martin , Kees Cook , Laura Abbott , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org idmap_kpti_install_ng_mappings uses x18 as a temporary register, which will result in a conflict when x18 is reserved. Use x16 and x17 instead where needed. Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Reviewed-by: Mark Rutland --- arch/arm64/mm/proc.S | 63 ++++++++++++++++++++++---------------------- 1 file changed, 32 insertions(+), 31 deletions(-) diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index a1e0592d1fbc..fdabf40a83c8 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -250,15 +250,15 @@ ENTRY(idmap_kpti_install_ng_mappings) /* We're the boot CPU. Wait for the others to catch up */ sevl 1: wfe - ldaxr w18, [flag_ptr] - eor w18, w18, num_cpus - cbnz w18, 1b + ldaxr w17, [flag_ptr] + eor w17, w17, num_cpus + cbnz w17, 1b /* We need to walk swapper, so turn off the MMU. */ pre_disable_mmu_workaround - mrs x18, sctlr_el1 - bic x18, x18, #SCTLR_ELx_M - msr sctlr_el1, x18 + mrs x17, sctlr_el1 + bic x17, x17, #SCTLR_ELx_M + msr sctlr_el1, x17 isb /* Everybody is enjoying the idmap, so we can rewrite swapper. */ @@ -281,9 +281,9 @@ skip_pgd: isb /* We're done: fire up the MMU again */ - mrs x18, sctlr_el1 - orr x18, x18, #SCTLR_ELx_M - msr sctlr_el1, x18 + mrs x17, sctlr_el1 + orr x17, x17, #SCTLR_ELx_M + msr sctlr_el1, x17 isb /* @@ -353,46 +353,47 @@ skip_pte: b.ne do_pte b next_pmd + .unreq cpu + .unreq num_cpus + .unreq swapper_pa + .unreq cur_pgdp + .unreq end_pgdp + .unreq pgd + .unreq cur_pudp + .unreq end_pudp + .unreq pud + .unreq cur_pmdp + .unreq end_pmdp + .unreq pmd + .unreq cur_ptep + .unreq end_ptep + .unreq pte + /* Secondary CPUs end up here */ __idmap_kpti_secondary: /* Uninstall swapper before surgery begins */ - __idmap_cpu_set_reserved_ttbr1 x18, x17 + __idmap_cpu_set_reserved_ttbr1 x16, x17 /* Increment the flag to let the boot CPU we're ready */ -1: ldxr w18, [flag_ptr] - add w18, w18, #1 - stxr w17, w18, [flag_ptr] +1: ldxr w16, [flag_ptr] + add w16, w16, #1 + stxr w17, w16, [flag_ptr] cbnz w17, 1b /* Wait for the boot CPU to finish messing around with swapper */ sevl 1: wfe - ldxr w18, [flag_ptr] - cbnz w18, 1b + ldxr w16, [flag_ptr] + cbnz w16, 1b /* All done, act like nothing happened */ - offset_ttbr1 swapper_ttb, x18 + offset_ttbr1 swapper_ttb, x16 msr ttbr1_el1, swapper_ttb isb ret - .unreq cpu - .unreq num_cpus - .unreq swapper_pa .unreq swapper_ttb .unreq flag_ptr - .unreq cur_pgdp - .unreq end_pgdp - .unreq pgd - .unreq cur_pudp - .unreq end_pudp - .unreq pud - .unreq cur_pmdp - .unreq end_pmdp - .unreq pmd - .unreq cur_ptep - .unreq end_ptep - .unreq pte ENDPROC(idmap_kpti_install_ng_mappings) .popsection #endif -- 2.24.0.393.g34dc348eaf-goog 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_ADSP_CUSTOM_MED,DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 2DA51C2BD09 for ; Fri, 6 Dec 2019 22:14:24 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F3A8C21835 for ; Fri, 6 Dec 2019 22:14:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="idZV2jNg"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="Sql0AUQx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F3A8C21835 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:To:From:Subject:References:Mime-Version :Message-Id:In-Reply-To:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=be6htXMttPf0+20ZSuy93LDpl73cdZeNfwpzV3CNIE0=; b=idZV2jNgOLd/jQ IlIthOYbfBpc52Moiv/z5dd39KYNdNuorRSsQYUcCS0w+fWY+fubRe11O+B1+to4gCXdekZjF9XwQ 0bIGUwhl1LurmMvB2ivHHuh5RhgJwDsWpM+kkObbS9UUPucAhltbMIKd36rLx6BQcnvz3ZY0CNn4N dVGSG3i8POCJ8kBhiwBdhUyuKf/EvSLX/659NrZcTIqthjguLpwwtCpdskldJcMTzSAwBgAKhplJV wMbHPD69SkiMy0eGtuXTMO05cTZNFtIiQhGBJRR91FUw87EtYUSryREtK18mf8B8L0Y8i8/1Vt9pt teLrGYmbkKxvpaieXUSA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1idLrf-0006h7-8g; Fri, 06 Dec 2019 22:14:19 +0000 Received: from mail-pf1-x449.google.com ([2607:f8b0:4864:20::449]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1idLrL-0006OT-Jl for linux-arm-kernel@lists.infradead.org; Fri, 06 Dec 2019 22:14:00 +0000 Received: by mail-pf1-x449.google.com with SMTP id x6so4796868pfx.8 for ; Fri, 06 Dec 2019 14:13:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Y+PZLTAB8cI7c6J3sLNCtDVk2nPLg4lB7Nz2OXbvgbI=; b=Sql0AUQx2FX2+C0fZujtdRKnpRimsqUsMS37x70l9M+sOZFbVJ3hWRwdsyDW5ACQD3 mAFiXZYiLY1AxLu49KVGTXlXxNh1yY51dVbs0fY+4RxUcDmlWjM22YiWJSg/QlijLlR+ LISSq0wh25qYppp+BCGBB3ASJ1IgdITLPyf57W++PmDhiZDO9WUYAB9cU3+NXaPjqcDE w4CLiFmNqW2XUK+Aroyl+dGcmQuxGGKW5WDjVx7vwC4+K9oGr9pTR8aiSWYEsabN9s4Z of4oOaIcSsRqcB6G4NGSbYRdfgN3Yi0kLtEC7/W0nA3ypJZva+dNrCITv6RcezBKGZVX zaWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Y+PZLTAB8cI7c6J3sLNCtDVk2nPLg4lB7Nz2OXbvgbI=; b=MA+UNvaTjyFkGXzIo+jfUWEi3YLyLA5kvpRtJITMRgm11OLaJ45nYPFHszb2GzqHyR tiwB47tzTJ+YsMhO/Gw6BSbLCNa2dWQghD2Nir38lhgowgIT8sjVrNwn9/KFNier8krT zK//9LlqPk1B8ZQsWK9lz6Vog+Lo/HejMeJXs5r77eaOrk4PNxUIWF9bmpCHlHY1KvND jX42W/NDdPK3ychEMh9JdQCG+iYUGYqofBK/7yMR4DdM9eALQxG7Sb1vnbF1xbydfaFz RUvAaAQe1eppaWXGxjm7FEL7bAWDC2MHkk9vzlcLNjDtpu8BnvwsCK8zu897cZt7Ja3h Evag== X-Gm-Message-State: APjAAAWMsGly0rH5JPQFeyPliE6TS3R0jMah/StKPcLbgWpGw+C39Wcj nUaYZF1RfMggDrJ5Quv/ths0YGy4P/SyyOD+v8A= X-Google-Smtp-Source: APXvYqywVZLwuqAoGiiDNrG08v6/3uqPLMW0Y7Sv/F1SLZBSFv5TaL7pDBX3rz4+Y7se97Kpozoy9je2n3q8Y+FKxcA= X-Received: by 2002:a63:de4a:: with SMTP id y10mr5991658pgi.367.1575670438461; Fri, 06 Dec 2019 14:13:58 -0800 (PST) Date: Fri, 6 Dec 2019 14:13:37 -0800 In-Reply-To: <20191206221351.38241-1-samitolvanen@google.com> Message-Id: <20191206221351.38241-2-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191206221351.38241-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.393.g34dc348eaf-goog Subject: [PATCH v6 01/15] arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191206_141359_647985_49726DCB X-CRM114-Status: UNSURE ( 9.89 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kees Cook , Jann Horn , Masahiro Yamada , Marc Zyngier , kernel-hardening@lists.openwall.com, Nick Desaulniers , linux-kernel@vger.kernel.org, Miguel Ojeda , clang-built-linux@googlegroups.com, Sami Tolvanen , Laura Abbott , Dave Martin , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org idmap_kpti_install_ng_mappings uses x18 as a temporary register, which will result in a conflict when x18 is reserved. Use x16 and x17 instead where needed. Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Reviewed-by: Mark Rutland --- arch/arm64/mm/proc.S | 63 ++++++++++++++++++++++---------------------- 1 file changed, 32 insertions(+), 31 deletions(-) diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index a1e0592d1fbc..fdabf40a83c8 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -250,15 +250,15 @@ ENTRY(idmap_kpti_install_ng_mappings) /* We're the boot CPU. Wait for the others to catch up */ sevl 1: wfe - ldaxr w18, [flag_ptr] - eor w18, w18, num_cpus - cbnz w18, 1b + ldaxr w17, [flag_ptr] + eor w17, w17, num_cpus + cbnz w17, 1b /* We need to walk swapper, so turn off the MMU. */ pre_disable_mmu_workaround - mrs x18, sctlr_el1 - bic x18, x18, #SCTLR_ELx_M - msr sctlr_el1, x18 + mrs x17, sctlr_el1 + bic x17, x17, #SCTLR_ELx_M + msr sctlr_el1, x17 isb /* Everybody is enjoying the idmap, so we can rewrite swapper. */ @@ -281,9 +281,9 @@ skip_pgd: isb /* We're done: fire up the MMU again */ - mrs x18, sctlr_el1 - orr x18, x18, #SCTLR_ELx_M - msr sctlr_el1, x18 + mrs x17, sctlr_el1 + orr x17, x17, #SCTLR_ELx_M + msr sctlr_el1, x17 isb /* @@ -353,46 +353,47 @@ skip_pte: b.ne do_pte b next_pmd + .unreq cpu + .unreq num_cpus + .unreq swapper_pa + .unreq cur_pgdp + .unreq end_pgdp + .unreq pgd + .unreq cur_pudp + .unreq end_pudp + .unreq pud + .unreq cur_pmdp + .unreq end_pmdp + .unreq pmd + .unreq cur_ptep + .unreq end_ptep + .unreq pte + /* Secondary CPUs end up here */ __idmap_kpti_secondary: /* Uninstall swapper before surgery begins */ - __idmap_cpu_set_reserved_ttbr1 x18, x17 + __idmap_cpu_set_reserved_ttbr1 x16, x17 /* Increment the flag to let the boot CPU we're ready */ -1: ldxr w18, [flag_ptr] - add w18, w18, #1 - stxr w17, w18, [flag_ptr] +1: ldxr w16, [flag_ptr] + add w16, w16, #1 + stxr w17, w16, [flag_ptr] cbnz w17, 1b /* Wait for the boot CPU to finish messing around with swapper */ sevl 1: wfe - ldxr w18, [flag_ptr] - cbnz w18, 1b + ldxr w16, [flag_ptr] + cbnz w16, 1b /* All done, act like nothing happened */ - offset_ttbr1 swapper_ttb, x18 + offset_ttbr1 swapper_ttb, x16 msr ttbr1_el1, swapper_ttb isb ret - .unreq cpu - .unreq num_cpus - .unreq swapper_pa .unreq swapper_ttb .unreq flag_ptr - .unreq cur_pgdp - .unreq end_pgdp - .unreq pgd - .unreq cur_pudp - .unreq end_pudp - .unreq pud - .unreq cur_pmdp - .unreq end_pmdp - .unreq pmd - .unreq cur_ptep - .unreq end_ptep - .unreq pte ENDPROC(idmap_kpti_install_ng_mappings) .popsection #endif -- 2.24.0.393.g34dc348eaf-goog _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel 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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 CB3BFC43603 for ; Fri, 6 Dec 2019 22:14:24 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 25738206DB for ; Fri, 6 Dec 2019 22:14:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Sql0AUQx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 25738206DB Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17473-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 17595 invoked by uid 550); 6 Dec 2019 22:14:11 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 17499 invoked from network); 6 Dec 2019 22:14:10 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=Y+PZLTAB8cI7c6J3sLNCtDVk2nPLg4lB7Nz2OXbvgbI=; b=Sql0AUQx2FX2+C0fZujtdRKnpRimsqUsMS37x70l9M+sOZFbVJ3hWRwdsyDW5ACQD3 mAFiXZYiLY1AxLu49KVGTXlXxNh1yY51dVbs0fY+4RxUcDmlWjM22YiWJSg/QlijLlR+ LISSq0wh25qYppp+BCGBB3ASJ1IgdITLPyf57W++PmDhiZDO9WUYAB9cU3+NXaPjqcDE w4CLiFmNqW2XUK+Aroyl+dGcmQuxGGKW5WDjVx7vwC4+K9oGr9pTR8aiSWYEsabN9s4Z of4oOaIcSsRqcB6G4NGSbYRdfgN3Yi0kLtEC7/W0nA3ypJZva+dNrCITv6RcezBKGZVX zaWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=Y+PZLTAB8cI7c6J3sLNCtDVk2nPLg4lB7Nz2OXbvgbI=; b=ikdgZufhSpOJteSSGopCWd5w+/2KFu5AuD23wbFrC67W+r5ArIUjV/f2VizPErNShp V3vk3/k31VB2rs5nZj7uAjzNIeyRhokem9wb5IOByUqCvg95lyOGZy7N4Bp7bRoETkny O2NsvLvH41LPn5li8v7Nc5OWD3kAM3RdXGwzQppNPxxcas+iLO6hn4WASdXjBDDgd6PQ GdGkZq6G3yJVEdSc8/RYvG3LFbyoUcMxezMQaQOIP+FxNziJyjukOu601/ld1SrzPWhP lLnv5oo6fLoV92OXW/qSqgSjLJ+D7qunlkZY7+qhsCCecQp82QnASe5Pr/k+QwEJitfK RESg== X-Gm-Message-State: APjAAAXczn/KlC3qNsOynRxTrRidKY3cGZJ30fRpHnK4ua5KiNogol1u YbTbCy7kliJcEzhpOjBJY2IFNQzfJhDnV8Exl9A= X-Google-Smtp-Source: APXvYqywVZLwuqAoGiiDNrG08v6/3uqPLMW0Y7Sv/F1SLZBSFv5TaL7pDBX3rz4+Y7se97Kpozoy9je2n3q8Y+FKxcA= X-Received: by 2002:a63:de4a:: with SMTP id y10mr5991658pgi.367.1575670438461; Fri, 06 Dec 2019 14:13:58 -0800 (PST) Date: Fri, 6 Dec 2019 14:13:37 -0800 In-Reply-To: <20191206221351.38241-1-samitolvanen@google.com> Message-Id: <20191206221351.38241-2-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191206221351.38241-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.393.g34dc348eaf-goog Subject: [PATCH v6 01/15] arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel , Mark Rutland Cc: Dave Martin , Kees Cook , Laura Abbott , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" idmap_kpti_install_ng_mappings uses x18 as a temporary register, which will result in a conflict when x18 is reserved. Use x16 and x17 instead where needed. Signed-off-by: Sami Tolvanen Reviewed-by: Nick Desaulniers Reviewed-by: Mark Rutland --- arch/arm64/mm/proc.S | 63 ++++++++++++++++++++++---------------------- 1 file changed, 32 insertions(+), 31 deletions(-) diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index a1e0592d1fbc..fdabf40a83c8 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -250,15 +250,15 @@ ENTRY(idmap_kpti_install_ng_mappings) /* We're the boot CPU. Wait for the others to catch up */ sevl 1: wfe - ldaxr w18, [flag_ptr] - eor w18, w18, num_cpus - cbnz w18, 1b + ldaxr w17, [flag_ptr] + eor w17, w17, num_cpus + cbnz w17, 1b /* We need to walk swapper, so turn off the MMU. */ pre_disable_mmu_workaround - mrs x18, sctlr_el1 - bic x18, x18, #SCTLR_ELx_M - msr sctlr_el1, x18 + mrs x17, sctlr_el1 + bic x17, x17, #SCTLR_ELx_M + msr sctlr_el1, x17 isb /* Everybody is enjoying the idmap, so we can rewrite swapper. */ @@ -281,9 +281,9 @@ skip_pgd: isb /* We're done: fire up the MMU again */ - mrs x18, sctlr_el1 - orr x18, x18, #SCTLR_ELx_M - msr sctlr_el1, x18 + mrs x17, sctlr_el1 + orr x17, x17, #SCTLR_ELx_M + msr sctlr_el1, x17 isb /* @@ -353,46 +353,47 @@ skip_pte: b.ne do_pte b next_pmd + .unreq cpu + .unreq num_cpus + .unreq swapper_pa + .unreq cur_pgdp + .unreq end_pgdp + .unreq pgd + .unreq cur_pudp + .unreq end_pudp + .unreq pud + .unreq cur_pmdp + .unreq end_pmdp + .unreq pmd + .unreq cur_ptep + .unreq end_ptep + .unreq pte + /* Secondary CPUs end up here */ __idmap_kpti_secondary: /* Uninstall swapper before surgery begins */ - __idmap_cpu_set_reserved_ttbr1 x18, x17 + __idmap_cpu_set_reserved_ttbr1 x16, x17 /* Increment the flag to let the boot CPU we're ready */ -1: ldxr w18, [flag_ptr] - add w18, w18, #1 - stxr w17, w18, [flag_ptr] +1: ldxr w16, [flag_ptr] + add w16, w16, #1 + stxr w17, w16, [flag_ptr] cbnz w17, 1b /* Wait for the boot CPU to finish messing around with swapper */ sevl 1: wfe - ldxr w18, [flag_ptr] - cbnz w18, 1b + ldxr w16, [flag_ptr] + cbnz w16, 1b /* All done, act like nothing happened */ - offset_ttbr1 swapper_ttb, x18 + offset_ttbr1 swapper_ttb, x16 msr ttbr1_el1, swapper_ttb isb ret - .unreq cpu - .unreq num_cpus - .unreq swapper_pa .unreq swapper_ttb .unreq flag_ptr - .unreq cur_pgdp - .unreq end_pgdp - .unreq pgd - .unreq cur_pudp - .unreq end_pudp - .unreq pud - .unreq cur_pmdp - .unreq end_pmdp - .unreq pmd - .unreq cur_ptep - .unreq end_ptep - .unreq pte ENDPROC(idmap_kpti_install_ng_mappings) .popsection #endif -- 2.24.0.393.g34dc348eaf-goog