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=-10.1 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,URIBL_BLOCKED,USER_AGENT_GIT 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 06648CA9EC7 for ; Wed, 30 Oct 2019 15:52:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CA7F520656 for ; Wed, 30 Oct 2019 15:52:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572450740; bh=bvGk2PFPjcyhGJhlCfWTtMGwXqeLi/+EaaoNSMmvMW0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ygFHR40PD8t7N3FCBvRMQ4ioAwCamQhwSQqd7iRGdgVnGwZgXQcmSdzm6lWRNjvqA 390ljW98Fgy+W2uNmXXTMHOroYOKmMZk0ZCwuE5Z+R0K9FXQNwXn4jwksPqBf40m1E jCfpnObYwb2i+Jcb3NzazWQCRLMvn2v0INVFRlPw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727985AbfJ3PwS (ORCPT ); Wed, 30 Oct 2019 11:52:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:53328 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727944AbfJ3PwS (ORCPT ); Wed, 30 Oct 2019 11:52:18 -0400 Received: from sasha-vm.mshome.net (100.50.158.77.rev.sfr.net [77.158.50.100]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A166A20874; Wed, 30 Oct 2019 15:52:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572450737; bh=bvGk2PFPjcyhGJhlCfWTtMGwXqeLi/+EaaoNSMmvMW0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZOcHu8tNQCkwJ69Je6c5u1rwo1lnw5+CPXV4xmzzYwWYOZeI18wlI5HL/jDLZvH7o 56mAVaoujoe4lB8ehV/sAYNxyj7DBi6Lko6bhRoAWEuWQaBjhY9fiB9F2OQ9wHVAqA 9UH65sBQqke6PYFjNDOuMXi3mO/RaFL/mzeUsvhY= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Masahiro Yamada , "kernelci.org bot" , Nicolas Saenz Julienne , Russell King , Sasha Levin Subject: [PATCH AUTOSEL 5.3 39/81] ARM: 8908/1: add __always_inline to functions called from __get_user_check() Date: Wed, 30 Oct 2019 11:48:45 -0400 Message-Id: <20191030154928.9432-39-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191030154928.9432-1-sashal@kernel.org> References: <20191030154928.9432-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Masahiro Yamada [ Upstream commit 851140ab0d083c78e5723a8b1cbd258f567a7aff ] KernelCI reports that bcm2835_defconfig is no longer booting since commit ac7c3e4ff401 ("compiler: enable CONFIG_OPTIMIZE_INLINING forcibly") (https://lkml.org/lkml/2019/9/26/825). I also received a regression report from Nicolas Saenz Julienne (https://lkml.org/lkml/2019/9/27/263). This problem has cropped up on bcm2835_defconfig because it enables CONFIG_CC_OPTIMIZE_FOR_SIZE. The compiler tends to prefer not inlining functions with -Os. I was able to reproduce it with other boards and defconfig files by manually enabling CONFIG_CC_OPTIMIZE_FOR_SIZE. The __get_user_check() specifically uses r0, r1, r2 registers. So, uaccess_save_and_enable() and uaccess_restore() must be inlined. Otherwise, those register assignments would be entirely dropped, according to my analysis of the disassembly. Prior to commit 9012d011660e ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING"), the 'inline' marker was always enough for inlining functions, except on x86. Since that commit, all architectures can enable CONFIG_OPTIMIZE_INLINING. So, __always_inline is now the only guaranteed way of forcible inlining. I added __always_inline to 4 functions in the call-graph from the __get_user_check() macro. Fixes: 9012d011660e ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING") Reported-by: "kernelci.org bot" Reported-by: Nicolas Saenz Julienne Signed-off-by: Masahiro Yamada Tested-by: Nicolas Saenz Julienne Signed-off-by: Russell King Signed-off-by: Sasha Levin --- arch/arm/include/asm/domain.h | 8 ++++---- arch/arm/include/asm/uaccess.h | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/arm/include/asm/domain.h b/arch/arm/include/asm/domain.h index 567dbede4785c..f1d0a7807cd0e 100644 --- a/arch/arm/include/asm/domain.h +++ b/arch/arm/include/asm/domain.h @@ -82,7 +82,7 @@ #ifndef __ASSEMBLY__ #ifdef CONFIG_CPU_CP15_MMU -static inline unsigned int get_domain(void) +static __always_inline unsigned int get_domain(void) { unsigned int domain; @@ -94,7 +94,7 @@ static inline unsigned int get_domain(void) return domain; } -static inline void set_domain(unsigned val) +static __always_inline void set_domain(unsigned int val) { asm volatile( "mcr p15, 0, %0, c3, c0 @ set domain" @@ -102,12 +102,12 @@ static inline void set_domain(unsigned val) isb(); } #else -static inline unsigned int get_domain(void) +static __always_inline unsigned int get_domain(void) { return 0; } -static inline void set_domain(unsigned val) +static __always_inline void set_domain(unsigned int val) { } #endif diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 303248e5b990f..98c6b91be4a8a 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -22,7 +22,7 @@ * perform such accesses (eg, via list poison values) which could then * be exploited for priviledge escalation. */ -static inline unsigned int uaccess_save_and_enable(void) +static __always_inline unsigned int uaccess_save_and_enable(void) { #ifdef CONFIG_CPU_SW_DOMAIN_PAN unsigned int old_domain = get_domain(); @@ -37,7 +37,7 @@ static inline unsigned int uaccess_save_and_enable(void) #endif } -static inline void uaccess_restore(unsigned int flags) +static __always_inline void uaccess_restore(unsigned int flags) { #ifdef CONFIG_CPU_SW_DOMAIN_PAN /* Restore the user access mask */ -- 2.20.1