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=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 0DB9DC04AAF for ; Thu, 16 May 2019 14:28:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DDCF320848 for ; Thu, 16 May 2019 14:28:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727483AbfEPO2C (ORCPT ); Thu, 16 May 2019 10:28:02 -0400 Received: from foss.arm.com ([217.140.101.70]:47602 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726696AbfEPO2B (ORCPT ); Thu, 16 May 2019 10:28:01 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 08ED91715; Thu, 16 May 2019 07:28:01 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A5EAA3F71E; Thu, 16 May 2019 07:27:59 -0700 (PDT) Date: Thu, 16 May 2019 15:27:57 +0100 From: Mark Rutland To: Steven Price Cc: Christoph Hellwig , linux-kernel@vger.kernel.org, Mike Rapoport , Andrew Morton , Will Deacon , Catalin Marinas Subject: Re: Bad virt_to_phys since commit 54c7a8916a887f35 Message-ID: <20190516142756.GE43059@lakrids.cambridge.arm.com> References: <20190516133820.GA43059@lakrids.cambridge.arm.com> <20190516134105.GB43059@lakrids.cambridge.arm.com> <20190516141640.GC43059@lakrids.cambridge.arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 16, 2019 at 03:20:59PM +0100, Steven Price wrote: > On 16/05/2019 15:16, Mark Rutland wrote: > > On Thu, May 16, 2019 at 03:05:31PM +0100, Steven Price wrote: > >> I suspect the following is sufficient to fix the problem: > >> > >> ----8<----- > >> diff --git a/init/initramfs.c b/init/initramfs.c > >> index 435a428c2af1..178130fd61c2 100644 > >> --- a/init/initramfs.c > >> +++ b/init/initramfs.c > >> @@ -669,7 +669,7 @@ static int __init populate_rootfs(void) > >> * If the initrd region is overlapped with crashkernel reserved region, > >> * free only memory that is not part of crashkernel region. > >> */ > >> - if (!do_retain_initrd && !kexec_free_initrd()) > >> + if (!do_retain_initrd && initrd_start && !kexec_free_initrd()) > >> free_initrd_mem(initrd_start, initrd_end); > >> initrd_start = 0; > >> initrd_end = 0; > > > > That works for me. If you spin this as a real patch: > > > > Tested-by: Mark Rutland > > > > As I mentioned, initrd_start has not been initialized at all, so I > > suspect we should also update its declaration in init/do_mounts_initrd.c > > such that it is guaranteed to be initialized to zero. We get away with > > that today, but that won't necessarily hold with LTO and so on... > > Well it's a global variable, so the C standard says it should be > initialised to 0... For some reason I was under the impression that wasn't guaranteed, but I see that it is. Sorry for the noise. > I'll spin a real patch and add your Tested-by Great; thanks! Mark.