From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935848AbeCBFdR (ORCPT ); Fri, 2 Mar 2018 00:33:17 -0500 Received: from mail-pl0-f65.google.com ([209.85.160.65]:39974 "EHLO mail-pl0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932845AbeCBFdO (ORCPT ); Fri, 2 Mar 2018 00:33:14 -0500 X-Google-Smtp-Source: AG47ELu/xqgszGB64SOOwbIklU2zAVxXXDOPS/EJO/NxAPoXQApYZ8ixhSOk3ZoX9mycwahNKsi+sQ== Date: Fri, 2 Mar 2018 14:33:26 +0900 From: AKASHI Takahiro To: Dave Young Cc: vgoyal@redhat.com, bhe@redhat.com, mpe@ellerman.id.au, bauerman@linux.vnet.ibm.com, prudo@linux.vnet.ibm.com, kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org Subject: Re: [PATCH 4/7] x86: kexec_file: remove X86_64 dependency from prepare_elf64_headers() Message-ID: <20180302053325.GO6019@linaro.org> Mail-Followup-To: AKASHI Takahiro , Dave Young , vgoyal@redhat.com, bhe@redhat.com, mpe@ellerman.id.au, bauerman@linux.vnet.ibm.com, prudo@linux.vnet.ibm.com, kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org References: <20180227044814.24808-1-takahiro.akashi@linaro.org> <20180227044814.24808-5-takahiro.akashi@linaro.org> <20180302051956.GB2952@dhcp-128-65.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180302051956.GB2952@dhcp-128-65.nay.redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 02, 2018 at 01:19:56PM +0800, Dave Young wrote: > On 02/27/18 at 01:48pm, AKASHI Takahiro wrote: > > The code guarded by CONFIG_X86_64 is necessary on some architectures > > which have a dedicated kernel mapping outside of linear memory mapping. > > (arm64 is among those.) > > > > In this patch, an additional argument, kernel_map, is added to enable/ > > disable the code removing #ifdef. > > > > Signed-off-by: AKASHI Takahiro > > Cc: Dave Young > > Cc: Vivek Goyal > > Cc: Baoquan He > > --- > > arch/x86/kernel/crash.c | 25 +++++++++++++------------ > > 1 file changed, 13 insertions(+), 12 deletions(-) > > > > diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c > > index 2123fa0efc17..913fd8021f8a 100644 > > --- a/arch/x86/kernel/crash.c > > +++ b/arch/x86/kernel/crash.c > > @@ -347,7 +347,7 @@ static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg) > > return 0; > > } > > > > -static int prepare_elf64_headers(struct crash_elf_data *ced, > > +static int prepare_elf64_headers(struct crash_elf_data *ced, int kernel_map, > > void **addr, unsigned long *sz) > > { > > Elf64_Ehdr *ehdr; > > @@ -414,17 +414,17 @@ static int prepare_elf64_headers(struct crash_elf_data *ced, > > phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE; > > (ehdr->e_phnum)++; > > > > -#ifdef CONFIG_X86_64 > > /* Prepare PT_LOAD type program header for kernel text region */ > > - phdr = (Elf64_Phdr *)bufp; > > - bufp += sizeof(Elf64_Phdr); > > - phdr->p_type = PT_LOAD; > > - phdr->p_flags = PF_R|PF_W|PF_X; > > - phdr->p_vaddr = (Elf64_Addr)_text; > > - phdr->p_filesz = phdr->p_memsz = _end - _text; > > - phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); > > - (ehdr->e_phnum)++; > > -#endif > > + if (kernel_map) { > > + phdr = (Elf64_Phdr *)bufp; > > + bufp += sizeof(Elf64_Phdr); > > + phdr->p_type = PT_LOAD; > > + phdr->p_flags = PF_R|PF_W|PF_X; > > + phdr->p_vaddr = (Elf64_Addr)_text; > > + phdr->p_filesz = phdr->p_memsz = _end - _text; > > + phdr->p_offset = phdr->p_paddr = __pa_symbol(_text); > > + (ehdr->e_phnum)++; > > + } > > > > /* Go through all the ranges in cmem->ranges[] and prepare phdr */ > > for (i = 0; i < cmem->nr_ranges; i++) { > > @@ -477,7 +477,8 @@ static int prepare_elf_headers(struct kimage *image, void **addr, > > goto out; > > > > /* By default prepare 64bit headers */ > > - ret = prepare_elf64_headers(ced, addr, sz); > > + ret = prepare_elf64_headers(ced, > > + (int)IS_ENABLED(CONFIG_X86_64), addr, sz); > > A bool would be enough for kernel_map Yeah, for now. What I thought of is that we might want to extend its functionality in the future as I did here for kernel_map without changing its interface. But I'd defer to you. -Takahiro AKASHI > > if (ret) > > goto out; > > > > Thanks > Dave > > -- > > 2.16.2 > >