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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 D3A2FC4360C for ; Thu, 26 Sep 2019 15:51:58 +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 AA61D222C9 for ; Thu, 26 Sep 2019 15:51:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="jO5Dhy5g" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA61D222C9 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:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=c1t452c8GqjUu+IO7ZonnJRhfk4kzoCn9HpRqh36Azo=; b=jO5Dhy5gAniU81 7nQ2GUXvqWgI/GG92iNRHRYE8BQOazB3GedLFbvD6UtxWDO5Hhgv99z6d6FuIw2PWO74Pu+W2ZIaT m/ibSA+B0dXb8XLPJ9Zn9mkENE/kZbyhMl7V1RM7KWsJobn9tpOtQU33bcskYrvGF01h6aoAP6+ue APiac9YB+nnGd7Qmg6ICNuwnZ6e10cHHugNvLA+BjyL/KTqkag62QUEQ7PqV445oGePupcQr3xhHT //zJxp44/5W6DqCtMXwAoGZd6ZOm813pz9f3BljhzQNR9n4uxoQE5cG0YyBiF0qHfPpnhDTsAZMTp kYTmONL6Ya9gNWPZsoCA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iDW3e-0005ql-Lx; Thu, 26 Sep 2019 15:51:54 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iDW3b-0005qQ-OX for linux-arm-kernel@lists.infradead.org; Thu, 26 Sep 2019 15:51:53 +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 DCE1028; Thu, 26 Sep 2019 08:51:50 -0700 (PDT) Received: from arrakis.emea.arm.com (arrakis.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id DA1793F534; Thu, 26 Sep 2019 08:51:49 -0700 (PDT) Date: Thu, 26 Sep 2019 16:51:47 +0100 From: Catalin Marinas To: Vincenzo Frascino Subject: Re: [PATCH] arm64: Allow disabling of the compat vDSO Message-ID: <20190926155147.GL9689@arrakis.emea.arm.com> References: <20190925130926.50674-1-catalin.marinas@arm.com> <20190925170838.GK7042@arrakis.emea.arm.com> <20190926074717.GA26802@iMac.local> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190926074717.GA26802@iMac.local> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190926_085151_843226_6DC11A71 X-CRM114-Status: GOOD ( 17.87 ) 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: Ard Biesheuvel , Nick Desaulniers , LKML , Thomas Gleixner , Will Deacon , Linux ARM 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 On Thu, Sep 26, 2019 at 08:47:18AM +0100, Catalin Marinas wrote: > On Thu, Sep 26, 2019 at 01:06:50AM +0100, Vincenzo Frascino wrote: > > On 9/25/19 6:08 PM, Catalin Marinas wrote: > > > On Wed, Sep 25, 2019 at 09:53:16AM -0700, Nick Desaulniers wrote: > > >> On Wed, Sep 25, 2019 at 6:09 AM Catalin Marinas wrote: > > >>> - clean up the headers includes; vDSO should not include kernel-only > > >>> headers that may even contain code patched at run-time > > >> > > >> This is a big one; Clang validates the inline asm constraints for > > >> extended inline assembly, GCC does not for dead code. So Clang chokes > > >> on the inclusion of arm64 headers using extended inline assembly when > > >> being compiled for arm-linux-gnueabi. > > > > > > Whether clang or gcc, I'd like this fixed anyway. At some point we may > > > inadvertently rely on some code which is patched at boot time for the > > > kernel code but not for the vDSO. > > > > Do we have any code of this kind in header files? > > > > The vDSO library uses only a subset of the headers (mainly Macros) hence all the > > unused symbols should be compiled out. Is your concern only theoretical or do > > you have an example on where this could be happening? > > At the moment it's rather theoretical. Actually, it's not. The moment the compat vdso Makefile needs the line below, we are doing it wrong: VDSO_CFLAGS += -D__uint128_t='void*' -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel