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=-5.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C3597C83000 for ; Tue, 28 Apr 2020 10:45:12 +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 887BF206E2 for ; Tue, 28 Apr 2020 10:45:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Dtg3owgz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 887BF206E2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.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:In-Reply-To:MIME-Version:Date: Message-ID:From:References:To:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=JI/56fFv4IiDtIvLFD+zUuBhbvAVVGrf2rgjl3zGnso=; b=Dtg3owgzK1wYb1 8FGzVSPms6YuOCj/vt4VSRWQJOv3lAh+Jl0S3yWI4RGORKYKilP4GUW/XgLwxKB1Ab+xjBpNo5lVl i3tVNO84k28oj8ucKmw6ZfH4R3ipG84TzLHZ/IooMjiwgXjs/Bap1t8p3cPLF0TiKtQXQvSe97MLM OQaJSFg5K2sv5lsYan+okL/sJ7maO8HtCZSVklzX1M6xFhj/9HmHaAPiCOvRpDA9eP+ivqYFv2Mzx II7XrFgopNFVNVpcosNzJL/LjgDpq0XAxYRrwzHtIulT2Cg7DPILkd6xOJuZMRWRaL1LGnkeG1Nku Yp0oSiE3dvHCmRkXr7LQ==; 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 1jTNjk-00063v-0r; Tue, 28 Apr 2020 10:45:12 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jTNjh-0004um-DP for linux-arm-kernel@lists.infradead.org; Tue, 28 Apr 2020 10:45:10 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2C65430E; Tue, 28 Apr 2020 03:45:06 -0700 (PDT) Received: from [10.37.8.217] (unknown [10.37.8.217]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2086B3F305; Tue, 28 Apr 2020 03:45:04 -0700 (PDT) Subject: Re: [PATCH] arm64/vdso: Remove unused makefile variable To: Will Deacon , Geoff Levand References: <20200427203520.GA23186@willie-the-truck> From: Vincenzo Frascino Message-ID: Date: Tue, 28 Apr 2020 11:46:03 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <20200427203520.GA23186@willie-the-truck> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200428_034509_505058_376C9A48 X-CRM114-Status: GOOD ( 17.06 ) 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: Catalin Marinas , linux-arm-kernel 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 Hi Will, thank you for pointing this out. On 4/27/20 9:35 PM, Will Deacon wrote: > [+Vincenzo] > > On Fri, Apr 24, 2020 at 08:58:49AM -0700, Geoff Levand wrote: >> The vdso makefile variable VDSO_LDFLAGS is defined, but never used, >> so remove it. >> >> Signed-off-by: Geoff Levand >> --- >> >> Hi, >> >> This seems to be left over from a code cleanup that missed it. > > While I agree that this isn't used, I'm wondering why '-Bsymbolic' is used > to link the compat vDSO but not the native one. It seems weird to differ > in this regard. > > Vincenzo? Looks like you added this unused variable in 28b1a824a4f44 > ("arm64: vdso: Substitute gettimeofday() with C implementation"). > My understanding is that "-Bsymbolic" is required by both compat and normal vdso because when the shared library is built it adds a flag in the dynamic section of the binary called DT_SYMBOLIC which alters the dynamic linker's symbol resolution algorithm to search for references for a symbol inside the library first and then into the executable. This becomes useful for example when an executable built with -fPIC is trying to call a public vDSO function from assembly (bl symbol). The issue here seems to be that I used VDSO_LDFLAGS instead of ldflags-y. I can post a patch and Cc stable. Adding Geoff as Reported-by. > Will > -- Regards, Vincenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel