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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_2 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 67AC5C3A5A0 for ; Mon, 20 Apr 2020 19:23:15 +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 34D3A2084D for ; Mon, 20 Apr 2020 19:23:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="VxMUe3Rv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 34D3A2084D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.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:MIME-Version:References:In-Reply-To: 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=FfQo2KT7rK+sFllDyAMY44kOkTZYnb3+jF9BETBYYZ8=; b=VxMUe3RvvvI//C XymlmXKiL/z6k0MeAmv12tSpH13V/7WX8zPovqSdB3ysYh2h4oM1+Zciku9oxnE6XZOwxesUyLzgh dV20wGB/lEH9fk9K+ipeLxM0su/0kmgnXBClWJlUWz91qvBSxMzgBEGbrAriSuw5XLdsM44H5um14 Xo609zzZw1CDcpujuhss8lOQqdpqohvV/Cuy5AliYE/27mYWfksGmvc5QVL47ram6AU1dmE0ynnsT H1ukMgKsesrJCkQdI3KdNELuNBJRfCgcorBbkW/EJv+3IIVSnEiZKzF0ovl5aDMDSo/Cl/ziDH9qS sfWwCKkxZYbq0U+u6c9w==; 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 1jQc0g-0003ME-Nk; Mon, 20 Apr 2020 19:23:14 +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 1jQc0d-0003Kp-M5 for linux-arm-kernel@lists.infradead.org; Mon, 20 Apr 2020 19:23:13 +0000 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (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 A3B5420736; Mon, 20 Apr 2020 19:23:07 +0000 (UTC) Date: Mon, 20 Apr 2020 15:23:06 -0400 From: Steven Rostedt To: Mark Rutland Subject: Re: [PATCH v11 04/12] scs: disable when function graph tracing is enabled Message-ID: <20200420152306.2d45e3c4@gandalf.local.home> In-Reply-To: <20200417154613.GB9529@lakrids.cambridge.arm.com> References: <20191018161033.261971-1-samitolvanen@google.com> <20200416161245.148813-1-samitolvanen@google.com> <20200416161245.148813-5-samitolvanen@google.com> <20200417100039.GS20730@hirez.programming.kicks-ass.net> <20200417144620.GA9529@lakrids.cambridge.arm.com> <20200417152645.GH20730@hirez.programming.kicks-ass.net> <20200417154613.GB9529@lakrids.cambridge.arm.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200420_122311_742356_2F0B9999 X-CRM114-Status: GOOD ( 12.20 ) 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: Juri Lelli , kernel-hardening@lists.openwall.com, Peter Zijlstra , Catalin Marinas , Will Deacon , Marc Zyngier , Masahiro Yamada , clang-built-linux@googlegroups.com, Ingo Molnar , Sami Tolvanen , Laura Abbott , Dave Martin , Kees Cook , Jann Horn , linux-arm-kernel@lists.infradead.org, Michal Marek , Ard Biesheuvel , Nick Desaulniers , linux-kernel@vger.kernel.org, Miguel Ojeda , James Morse , Masami Hiramatsu 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 Fri, 17 Apr 2020 16:46:14 +0100 Mark Rutland wrote: > > > > And doesn't BPF also do stuff like this? > > > > > > Can BPF mess with return addresses now!? > > > > At least on x86 I think it does. But what do I know, I can't operate > > that stuff. Rostedt might know. > > Sounds like I might need to do some digging... May want to ping Alexei. It appears that if BPF adds a direct hook to a function, it will prevent the function graph tracer from tracing it. :-/ -- Steve _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel