Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754642AbbGFRD2 (ORCPT ); Mon, 6 Jul 2015 13:03:28 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:40454 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753864AbbGFRD1 (ORCPT ); Mon, 6 Jul 2015 13:03:27 -0400 Message-ID: <559AB49F.3070008@oracle.com> Date: Mon, 06 Jul 2015 13:02:23 -0400 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Ingo Molnar CC: Denys Vlasenko , linux-kernel@vger.kernel.org, Andy Lutomirski , Brian Gerst , Peter Zijlstra , Borislav Petkov , "H. Peter Anvin" , Linus Torvalds , Oleg Nesterov , Thomas Gleixner Subject: Re: [PATCH] x86/asm/entry/64: Clean up entry_64.S References: <1433752501-15901-1-git-send-email-mingo@kernel.org> <1433752501-15901-5-git-send-email-mingo@kernel.org> <5575954F.5070408@redhat.com> <20150608185106.GA28747@gmail.com> <559A9821.4010600@oracle.com> <20150706160737.GA6462@gmail.com> <559AAA7A.7080100@oracle.com> <20150706162359.GA16523@gmail.com> <559AAE8F.1050408@oracle.com> <20150706164330.GA24890@gmail.com> In-Reply-To: <20150706164330.GA24890@gmail.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2798 Lines: 81 On 07/06/2015 12:43 PM, Ingo Molnar wrote: > > * Sasha Levin wrote: > >> On 07/06/2015 12:23 PM, Ingo Molnar wrote: >>> >>> * Sasha Levin wrote: >>> >>>> On 07/06/2015 12:07 PM, Ingo Molnar wrote: >>>>> >>>>> * Sasha Levin wrote: >>>>> >>>>>> Hey Ingo, >>>>>> >>>>>> I've started seeing the fuzzer hitting the BUG() at arch/x86/kernel/nmi.c:533. git >>>>>> blame pointed to this patch. I know that you didn't see any changes in the compiled >>>>>> file in your testcase, but I do see changes in mine. >>>>> >>>>> Hm, weird - could you send me your .config please? >>>> >>>> Attached. >>> >>> It's still weird: I copied your config to 4d7321381e5c and made 'make oldconfig' - >>> and it asked a couple of questions, which suggests that your config does not come >>> from 4d7321381e5c? >> >> Right, sorry, this is my base config for -next. I just did 'yes "" | make oldconfig' >> for the build test. >> >> I've attached it. >> >>> Furthermore, building 4d7321381e5c and 4d7321381e5c^1 gives me: >>> >>> # arch/x86/entry/entry_64.o: >>> >>> text data bss dec hex filename >>> 11530 0 0 11530 2d0a entry_64.o.before >>> 11530 0 0 11530 2d0a entry_64.o.after >>> >>> md5: >>> 1430e793250d5d8572bc2df2997d3929 entry_64.o.before.asm >>> 1430e793250d5d8572bc2df2997d3929 entry_64.o.after.asm >>> >>> i.e. I have trouble reproducing the discrepancy you are seeing. (I also tried >>> allmodconfig/allyesconfig again for good measure - no luck.) >> >> With allyesconfig I don't actually see a change. Only with the config I've attached. > > So I still cannot reproduce it even with your latest config: > > # arch/x86/entry/entry_64.o: > > text data bss dec hex filename > 11530 0 0 11530 2d0a entry_64.o.before > 11530 0 0 11530 2d0a entry_64.o.after > > md5: > 1430e793250d5d8572bc2df2997d3929 entry_64.o.before.asm > 1430e793250d5d8572bc2df2997d3929 entry_64.o.after.asm > > but I saw this during the build: > > scripts/Makefile.kasan:23: CONFIG_KASAN: compiler does not support all options. Trying minimal configuration > > is your KASAN build more fully enabled, and does the problem reproduce with > CONFIG_KASAN turned off? KASAN was fully enabled, but this reproduces with CONFIG_KASAN turned off as well. I also thought that it might be because I'm using gcc6, but going back to 4.7.2 produced the same difference. Thanks, Sasha -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/