From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gnu.wildebeest.org (gnu.wildebeest.org [45.83.234.184]) by sourceware.org (Postfix) with ESMTPS id A4B353858D1E for ; Thu, 28 Apr 2022 19:56:50 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org A4B353858D1E Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=klomp.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=klomp.org Received: by gnu.wildebeest.org (Postfix, from userid 1000) id 7C203302BBED; Thu, 28 Apr 2022 21:56:49 +0200 (CEST) Date: Thu, 28 Apr 2022 21:56:49 +0200 From: Mark Wielaard To: German Gomez Cc: elfutils-devel@sourceware.org Subject: Re: [PATCH 0/4] Add AARCH64 pointer authentication support Message-ID: <20220428195649.GF23335@gnu.wildebeest.org> References: <20220425140311.95231-1-german.gomez@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220425140311.95231-1-german.gomez@arm.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Spam-Status: No, score=-3.8 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: elfutils-devel@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Elfutils-devel mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Apr 2022 19:56:52 -0000 Hi German, On Mon, Apr 25, 2022 at 02:03:07PM +0000, German Gomez via Elfutils-devel wrote: > I've included a set of patches in order to demangle return addresses in > aarch64 platforms with pointer authentication. > > Besides adding the implementation of the negate_ra_state opcode, there > is a new function in the libdwfl.h header to feed the PAC masks to the > library. > > Let me know if there are any concerns with the current version. Thanks a lot for this. Last time I looked at this didn't have any means to test this, so I skipped implementing it. How did you test? Do distributions now enable PAC by default and is there hardware (qemu?) support? I haven't been able to look at the actual patches yet. And I am on vacation this week. But I'll review next week after I am back. A quick scan shows we need a aarch64 special public function, which would be slightly ugly imho. I had hoped it could be a variant of the func_addr_mask. But maybe this is too different to make more generic. Cheers, Mark