Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033869AbdDUAyh (ORCPT ); Thu, 20 Apr 2017 20:54:37 -0400 Received: from mx1.redhat.com ([209.132.183.28]:52400 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1033943AbdDUAyc (ORCPT ); Thu, 20 Apr 2017 20:54:32 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 4BF32811AC Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=xpang@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 4BF32811AC Reply-To: xlpang@redhat.com Subject: Re: [PATCH v4 2/3] powerpc/fadump: Use the correct VMCOREINFO_NOTE_SIZE for phdr References: <1492688374-27903-1-git-send-email-xlpang@redhat.com> <1492688374-27903-2-git-send-email-xlpang@redhat.com> To: Xunlei Pang , linux-kernel@vger.kernel.org, kexec@lists.infradead.org Cc: Baoquan He , Petr Tesarik , Eric Biederman , Hari Bathini , akpm@linux-foundation.org, Dave Young , Michael Holzheu From: Xunlei Pang Message-ID: <58F95887.3090404@redhat.com> Date: Fri, 21 Apr 2017 08:55:35 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: <1492688374-27903-2-git-send-email-xlpang@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Fri, 21 Apr 2017 00:54:31 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2634 Lines: 75 Cc "Michael Holzheu" On 04/20/2017 at 07:39 PM, Xunlei Pang wrote: > vmcoreinfo_max_size stands for the vmcoreinfo_data, the > correct one we should use is vmcoreinfo_note whose total > size is VMCOREINFO_NOTE_SIZE. > > Like explained in commit 77019967f06b ("kdump: fix exported > size of vmcoreinfo note"), it should not affect the actual > function, but we better fix it, also this change should be > safe and backward compatible. > > After this, we can get rid of variable vmcoreinfo_max_size, > let's use the corresponding macros directly, fewer variables > means more safety for vmcoreinfo operation. > > Cc: Mahesh Salgaonkar > Cc: Hari Bathini > Signed-off-by: Xunlei Pang > --- > v3->v4: > -Rebased on the latest linux-next > > arch/powerpc/kernel/fadump.c | 3 +-- > include/linux/crash_core.h | 1 - > kernel/crash_core.c | 3 +-- > 3 files changed, 2 insertions(+), 5 deletions(-) > > diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c > index 466569e..7bd6cd0 100644 > --- a/arch/powerpc/kernel/fadump.c > +++ b/arch/powerpc/kernel/fadump.c > @@ -893,8 +893,7 @@ static int fadump_create_elfcore_headers(char *bufp) > > phdr->p_paddr = fadump_relocate(paddr_vmcoreinfo_note()); > phdr->p_offset = phdr->p_paddr; > - phdr->p_memsz = vmcoreinfo_max_size; > - phdr->p_filesz = vmcoreinfo_max_size; > + phdr->p_memsz = phdr->p_filesz = VMCOREINFO_NOTE_SIZE; > > /* Increment number of program headers. */ > (elf->e_phnum)++; > diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h > index ba283a2..7d6bc7b 100644 > --- a/include/linux/crash_core.h > +++ b/include/linux/crash_core.h > @@ -55,7 +55,6 @@ > > extern u32 *vmcoreinfo_note; > extern size_t vmcoreinfo_size; > -extern size_t vmcoreinfo_max_size; > > Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, > void *data, size_t data_len); > diff --git a/kernel/crash_core.c b/kernel/crash_core.c > index 0321f04..43cdb00 100644 > --- a/kernel/crash_core.c > +++ b/kernel/crash_core.c > @@ -16,7 +16,6 @@ > /* vmcoreinfo stuff */ > static unsigned char *vmcoreinfo_data; > size_t vmcoreinfo_size; > -size_t vmcoreinfo_max_size = VMCOREINFO_BYTES; > u32 *vmcoreinfo_note; > > /* > @@ -343,7 +342,7 @@ void vmcoreinfo_append_str(const char *fmt, ...) > r = vscnprintf(buf, sizeof(buf), fmt, args); > va_end(args); > > - r = min(r, vmcoreinfo_max_size - vmcoreinfo_size); > + r = min(r, VMCOREINFO_BYTES - vmcoreinfo_size); > > memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r); >