From patchwork Mon Mar 8 12:31:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 395901 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, 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 7CB79C4321A for ; Mon, 8 Mar 2021 12:35:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B289651FC for ; Mon, 8 Mar 2021 12:35:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231424AbhCHMev (ORCPT ); Mon, 8 Mar 2021 07:34:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:43474 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231314AbhCHMeg (ORCPT ); Mon, 8 Mar 2021 07:34:36 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id C22F8651CF; Mon, 8 Mar 2021 12:34:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1615206876; bh=glepnS2PyHI4cIirF6sXbPDf6waIMx8obG42NtzmUmo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1WfwevuresGkZ6FllRbAlRgCF/8xZOAFiqDfzxaxugTHYWdvDRqs3DUVCx8c1W7TG 3Md8YjK/KzSr+doRO0cmPTONZ4JMn/N+j9TS/a1mvoARnoBNnjDFtVRYG0iXAgQI2f j0+2Jxe0oC5sDyr/Ycpek60pqLPbr8qE5/y8ej/M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Will Deacon , Chen Jun , "Steven Rostedt (VMware)" , Sasha Levin Subject: [PATCH 5.10 36/42] ftrace: Have recordmcount use w8 to read relp->r_info in arm64_is_fake_mcount Date: Mon, 8 Mar 2021 13:31:02 +0100 Message-Id: <20210308122719.881477587@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210308122718.120213856@linuxfoundation.org> References: <20210308122718.120213856@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Chen Jun [ Upstream commit 999340d51174ce4141dd723105d4cef872b13ee9 ] On little endian system, Use aarch64_be(gcc v7.3) downloaded from linaro.org to build image with CONFIG_CPU_BIG_ENDIAN = y, CONFIG_FTRACE = y, CONFIG_DYNAMIC_FTRACE = y. gcc will create symbols of _mcount but recordmcount can not create mcount_loc for *.o. aarch64_be-linux-gnu-objdump -r fs/namei.o | grep mcount 00000000000000d0 R_AARCH64_CALL26 _mcount ... 0000000000007190 R_AARCH64_CALL26 _mcount The reason is than funciton arm64_is_fake_mcount can not work correctly. A symbol of _mcount in *.o compiled with big endian compiler likes: 00 00 00 2d 00 00 01 1b w(rp->r_info) will return 0x2d instead of 0x011b. Because w() takes uint32_t as parameter, which truncates rp->r_info. Use w8() instead w() to read relp->r_info Link: https://lkml.kernel.org/r/20210222135840.56250-1-chenjun102@huawei.com Fixes: ea0eada45632 ("recordmcount: only record relocation of type R_AARCH64_CALL26 on arm64.") Acked-by: Will Deacon Signed-off-by: Chen Jun Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin --- scripts/recordmcount.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/recordmcount.c b/scripts/recordmcount.c index b9c2ee7ab43f..cce12e1971d8 100644 --- a/scripts/recordmcount.c +++ b/scripts/recordmcount.c @@ -438,7 +438,7 @@ static int arm_is_fake_mcount(Elf32_Rel const *rp) static int arm64_is_fake_mcount(Elf64_Rel const *rp) { - return ELF64_R_TYPE(w(rp->r_info)) != R_AARCH64_CALL26; + return ELF64_R_TYPE(w8(rp->r_info)) != R_AARCH64_CALL26; } /* 64-bit EM_MIPS has weird ELF64_Rela.r_info.