Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933990AbdCVHkU (ORCPT ); Wed, 22 Mar 2017 03:40:20 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:32848 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752115AbdCVHjo (ORCPT ); Wed, 22 Mar 2017 03:39:44 -0400 Subject: Re: [PATCH v2 02/10] x86: assembly, FUNC_START for fn, DATA_START for data To: Ingo Molnar , Pavel Machek , Josh Poimboeuf References: <9ea5e137-61f9-dccc-bb9d-ac3ff86e5867@suse.cz> <20170320123222.15453-1-jslaby@suse.cz> <20170320123222.15453-2-jslaby@suse.cz> <20170321140840.GA23311@amd> <20170322072557.GA13904@gmail.com> Cc: mingo@redhat.com, tglx@linutronix.de, hpa@zytor.com, x86@kernel.org, linux-kernel@vger.kernel.org, Boris Ostrovsky , Juergen Gross , xen-devel@lists.xenproject.org, "Rafael J. Wysocki" , Len Brown , linux-pm@vger.kernel.org From: Jiri Slaby Message-ID: Date: Wed, 22 Mar 2017 08:39:40 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170322072557.GA13904@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1317 Lines: 44 On 03/22/2017, 08:25 AM, Ingo Molnar wrote: > > * Pavel Machek wrote: > >> Hi! >> >>> -ENTRY(saved_rbp) .quad 0 >>> -ENTRY(saved_rsi) .quad 0 >>> -ENTRY(saved_rdi) .quad 0 >>> -ENTRY(saved_rbx) .quad 0 >>> +SYM_DATA_START(saved_rbp) .quad 0 >>> +SYM_DATA_START(saved_rsi) .quad 0 >>> +SYM_DATA_START(saved_rdi) .quad 0 >>> +SYM_DATA_START(saved_rbx) .quad 0 >> >> Does it make sense to call it SYM_DATA_*START* when there's no >> corresponding end? > > That looks like a bug - I think we should strive for them to always be in pairs. > > Jiri, Josh, could objtool help here perhaps, to detect 'non-terminated' > SYM_*_START() uses? This could be done by emitting debug data into a special > section and then analyzing that section for unpaired entries. The section can be > discarded in the final link, it won't show up in the kernel image. It should be easier than that. No introduction of other info needed -- every global symbol without a ".type" or ".size" (i.e. SYM_*_END) should be a bug now. > We don't ever nest symbols, right? AFAI could see so far, correct. >> Plus... it looks like saved_rsi (and friends) are only used inside >> wakeup_64.S. Could we just delete the "ENTRY" annotations? > > That appears to make sense as well. +1, will fix this. thanks, -- js suse labs