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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 A9D0FC47247 for ; Tue, 5 May 2020 16:09:01 +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 7BA8F206A4 for ; Tue, 5 May 2020 16:09:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="QgRbJKwk"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="u03NNzA/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7BA8F206A4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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=ifjf8HIzCchu3GPrKx8CwXbwVdX0TQDQmo7P88pc9Oc=; b=QgRbJKwkVNnSuM 53PabxT31rnQh3I94a8wrFKbbvGX9L1kToJS1WGesT5CLlb9uejEXpF17hUwBxi1Ql/8f7sjlfBja +uOqBPU7BZEkhHmwfG3rtG3mKvmKnJ8sfcURgj3yAFYc6P0Mvl71EmgK02yFSRuVDZz0kVfckAiXN el8YFowjsk1bBuKHlnaIC+xuZfyvl8JpV8H//HuCONWewpxqkzXai7s4OyRP9x3WeeDIpjFOazPGQ zjgzbEi6PlcFsWR89zlDPRKmUKtCiTaN3dE9qk2SPLZUzMhw9U4kczl9yQAfx4gNWHX4aTGm5u6WG zdJeLI3JQNGHzC7x6ytQ==; 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 1jW07x-0007sx-2O; Tue, 05 May 2020 16:09:01 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jW07u-0007sH-EE for linux-arm-kernel@lists.infradead.org; Tue, 05 May 2020 16:08:59 +0000 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BDAC6206B9; Tue, 5 May 2020 16:08:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588694937; bh=F59id0G0m99O8tp4MEKXifyCEQUtPEYauH+UoGyh24A=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=u03NNzA/DY25HLT4fsFpXTK6V2AwWdwqmx/7hwuzbaIj6r4iDmUecWuF+E6RW7vm4 /G8UFKhkLZrLJXKmAGUmIv8o1ppyIEQsdJWM7/uTJn/gM50F29U6sLSa8yN7nAL7u1 HpPKARvtomuj6n5nGJtCizfqKRR4cAwE+gL8rQ/w= Date: Tue, 5 May 2020 17:08:53 +0100 From: Will Deacon To: Mark Brown Subject: Re: [PATCH v2 02/10] arm64: asm: Override SYM_FUNC_START when building the kernel with BTI Message-ID: <20200505160852.GF24239@willie-the-truck> References: <20200429211641.9279-1-broonie@kernel.org> <20200429211641.9279-3-broonie@kernel.org> <20200505145642.GA24239@willie-the-truck> <20200505151806.GG5377@sirena.org.uk> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200505151806.GG5377@sirena.org.uk> 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-20200505_090858_500305_6564B886 X-CRM114-Status: GOOD ( 15.84 ) 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 , Vincenzo Frascino , Kees Cook , 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 On Tue, May 05, 2020 at 04:18:06PM +0100, Mark Brown wrote: > On Tue, May 05, 2020 at 03:56:42PM +0100, Will Deacon wrote: > > On Wed, Apr 29, 2020 at 10:16:33PM +0100, Mark Brown wrote: > > > > +#define SYM_INNER_LABEL(name, linkage) \ > > > + .type name SYM_T_NONE ASM_NL \ > > > + SYM_ENTRY(name, linkage, SYM_A_NONE) \ > > > + BTI_J > > > This break building the compat vDSO: > > Right, fixed locally. Thanks! > > I also see a scary linker warning about the native VDSO: > > > aarch64-none-linux-gnu-ld: arch/arm64/kernel/vdso/vgettimeofday.o: warning: BTI turned on by -z force-bti when all inputs do not have BTI in NOTE section. > > I can't reproduce this, I am using clang-10 as well... can you share > your exact command line and config? I'm using > > make -j56 ARCH=arm64 CROSS_COMPILE=aarch64-none-linux-gnu- CC=clang-10 > > which is the same clang version as you, not that I'd expect that to make > a difference. This looks like the C code isn't being built with BTI > enabled but I can't see how you're managing to do that and I'm not - > this is the warning that "arm64: vdso: Force the VDSO to be linked as > BTI when built for BTI" is intended to trigger if something goes wrong > so I guess it's a good job I enabled that :/ Just been debugging this, and it seems that not all clangs are created equal. Updating mine from 10.0.2 to 11.0.1 means I now get the '.note.gnu.property' sections emitted for C files compiled using '-mbranch-protection=pac-ret+leaf+bti', whereas I didn't before. Cheers, Will _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel