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, URIBL_BLOCKED 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 04083C12002 for ; Wed, 14 Jul 2021 20:09:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D0A57613C3 for ; Wed, 14 Jul 2021 20:09:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239583AbhGNUMF (ORCPT ); Wed, 14 Jul 2021 16:12:05 -0400 Received: from out03.mta.xmission.com ([166.70.13.233]:55832 "EHLO out03.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238029AbhGNUMD (ORCPT ); Wed, 14 Jul 2021 16:12:03 -0400 Received: from in02.mta.xmission.com ([166.70.13.52]:37656) by out03.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1m3lBu-00G2fD-3g; Wed, 14 Jul 2021 14:09:10 -0600 Received: from ip68-227-160-95.om.om.cox.net ([68.227.160.95]:50644 helo=email.xmission.com) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1m3lBs-008XEt-12; Wed, 14 Jul 2021 14:09:09 -0600 From: ebiederm@xmission.com (Eric W. Biederman) To: Linus Torvalds Cc: Nick Desaulniers , Miguel Ojeda , Greg Kroah-Hartman , rust-for-linux , Linux Kbuild mailing list , "open list\:DOCUMENTATION" , Linux Kernel Mailing List , Alex Gaynor , Geoffrey Thomas , Finn Behrens , Adam Bratschi-Kaye , Wedson Almeida Filho References: <20210704202756.29107-1-ojeda@kernel.org> <20210704202756.29107-3-ojeda@kernel.org> Date: Wed, 14 Jul 2021 15:09:01 -0500 In-Reply-To: (Linus Torvalds's message of "Wed, 14 Jul 2021 12:04:08 -0700") Message-ID: <87mtqo1wv6.fsf@disp2133> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-XM-SPF: eid=1m3lBs-008XEt-12;;;mid=<87mtqo1wv6.fsf@disp2133>;;;hst=in02.mta.xmission.com;;;ip=68.227.160.95;;;frm=ebiederm@xmission.com;;;spf=neutral X-XM-AID: U2FsdGVkX1+RhqiLRuXkUrC80vE88JVm8tG24B3OT+w= X-SA-Exim-Connect-IP: 68.227.160.95 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: Re: [PATCH 02/17] kallsyms: increase maximum kernel symbol length to 512 X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org Linus Torvalds writes: > On Wed, Jul 14, 2021 at 11:20 AM Nick Desaulniers > wrote: >> >> Do we demangle rust symbols when printing a trace from a warn/panic? >> That would be nice. > > I think it would be pretty much required. Otherwise stack traces are > going to be very very painful. > > In fact, I'm starting to think that Willy is right: we should use > hashes for the "real" symbol name, and have demangled names for > printing, and at no point would the kernel actually want or need to > have the nasty mangled names. > > (This wouldn't be rust-specific - using hashes for module linking > sounds like a good diea for C code as well, even if the de-mangled > names for printing are then the regular ones) > > Anybody interested in looking into that? It would make this "big > kernel symbols" patch immaterial. Are you thinking the hashed kernel symbols need to have their types included in the hash? Or is this just a hash to make the names a managable size? Eric