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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 040DAC433DB for ; Tue, 22 Dec 2020 21:39:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8FEB22AAE for ; Tue, 22 Dec 2020 21:39:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728005AbgLVVjV (ORCPT ); Tue, 22 Dec 2020 16:39:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727344AbgLVVjU (ORCPT ); Tue, 22 Dec 2020 16:39:20 -0500 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E32D1C0613D3; Tue, 22 Dec 2020 13:38:39 -0800 (PST) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1krpMZ-003KnC-QC; Tue, 22 Dec 2020 21:38:35 +0000 Date: Tue, 22 Dec 2020 21:38:35 +0000 From: Al Viro To: "Maciej W. Rozycki" Cc: Linus Torvalds , Thomas Bogendoerfer , Linux Kernel Mailing List , the arch/x86 maintainers , linux-mips@vger.kernel.org, Randy Dunlap Subject: Re: [PATCHSET] saner elf compat Message-ID: <20201222213835.GU3579531@ZenIV.linux.org.uk> References: <20201203214529.GB3579531@ZenIV.linux.org.uk> <20201203230336.GC3579531@ZenIV.linux.org.uk> <20201216030154.GL3579531@ZenIV.linux.org.uk> <20201222200431.GT3579531@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201222200431.GT3579531@ZenIV.linux.org.uk> Sender: Al Viro Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 22, 2020 at 08:04:31PM +0000, Al Viro wrote: > FWIW, on debian/mips64el (both stretch and buster) the test fails with the > distro kernels (4.9- and 4.19-based) as well as with 5.10-rc1 and > 5.10-rc1+that series, all in the same way: > [Current thread is 1 (LWP 4154)] > (gdb) p/x foo > Cannot find thread-local storage for LWP 4154, executable file > Cannot find thread-local variables on this target > > buster has libc6-2.28, so that should be fine for the test in question > (libthread_db definitely recent enough). That was n32 gdb; considering > how much time it had taken to build that sucker I hadn't tried o32 > yet. > > Note that it's not just with native coredumps - gcore-produced ones give > the same result. That was gdb from binutils-gdb.git; I'm not familiar > with gdb guts to start debugging it, so if you have any suggestions > in that direction that do not include a full rebuild... In any case, > I won't get around to that until the next week. > > Incidentally, build time is bloody awful - 3 days, with qemu-3.1 on > 3.5GHz amd64 host, all spent pretty much entirely in userland (both > from guest and host POV). g++-8 is atrociously slow... > > That said, I don't see what in that series could possibly mess the > things up for tls, while leaving the registers working; the only > thing that realistically might've been fucked up is prstatus layout > (and possibly size), and that would've screwed the registers as > well. ... and it smells like the damn thing needs n32 debug info from libthread_db.so and/or libpthread.so. Which is not packaged by debian libc6 mips64el build. Sorry, any debugging of that crap is going to happen in January ;-/