From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mtagate3.uk.ibm.com ([194.196.100.163]) by canuck.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1Qrs6w-0001x2-Pk for kexec@lists.infradead.org; Fri, 12 Aug 2011 13:49:21 +0000 Received: from d06nrmr1707.portsmouth.uk.ibm.com (d06nrmr1707.portsmouth.uk.ibm.com [9.149.39.225]) by mtagate3.uk.ibm.com (8.13.1/8.13.1) with ESMTP id p7CDn9Hw029982 for ; Fri, 12 Aug 2011 13:49:09 GMT Received: from d06av12.portsmouth.uk.ibm.com (d06av12.portsmouth.uk.ibm.com [9.149.37.247]) by d06nrmr1707.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p7CDn8nY1499366 for ; Fri, 12 Aug 2011 14:49:08 +0100 Received: from d06av12.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av12.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p7CDn7CO001275 for ; Fri, 12 Aug 2011 07:49:08 -0600 Message-Id: <20110812134907.325789470@linux.vnet.ibm.com> Date: Fri, 12 Aug 2011 15:48:52 +0200 From: Michael Holzheu Subject: [patch v3 3/8] kdump: Add size to elfcorehdr kernel parameter References: <20110812134849.748973593@linux.vnet.ibm.com> Content-Disposition: inline; filename=s390-kdump-common-elfcorehdr-parm.patch List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: vgoyal@redhat.com Cc: oomichi@mxs.nes.nec.co.jp, linux-s390@vger.kernel.org, mahesh@linux.vnet.ibm.com, heiko.carstens@de.ibm.com, linux-kernel@vger.kernel.org, hbabu@us.ibm.com, horms@verge.net.au, ebiederm@xmission.com, schwidefsky@de.ibm.com, kexec@lists.infradead.org From: Michael Holzheu Currently only the address of the pre-allocated ELF header is passed with the elfcorehdr= kernel parameter. In order to reserve memory for the header in the 2nd kernel also the size is required. Current kdump architecture backends use different methods to do that, e.g. x86 uses the memmap= kernel parameter. On s390 there is no easy way to transfer this information. Therefore the elfcorehdr kernel parameter is extended to also pass the size. This now can also be used as standard mechanism by all future kdump architecture backends. The syntax of the kernel parameter is extended as follows: elfcorehdr=[size[KMG]@]offset[KMG] This change is backward compatible because elfcorehdr=size is still allowed. Signed-off-by: Michael Holzheu --- Documentation/kernel-parameters.txt | 6 +++--- include/linux/crash_dump.h | 1 + kernel/crash_dump.c | 11 +++++++++++ 3 files changed, 15 insertions(+), 3 deletions(-) --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -725,10 +725,10 @@ bytes respectively. Such letter suffixes See Documentation/block/as-iosched.txt and Documentation/block/deadline-iosched.txt for details. - elfcorehdr= [IA64,PPC,SH,X86] + elfcorehdr=[size[KMG]@]offset[KMG] [IA64,PPC,SH,X86,S390] Specifies physical address of start of kernel core - image elf header. Generally kexec loader will - pass this option to capture kernel. + image elf header and optionally the size. Generally + kexec loader will pass this option to capture kernel. See Documentation/kdump/kdump.txt for details. enable_mtrr_cleanup [X86] --- a/include/linux/crash_dump.h +++ b/include/linux/crash_dump.h @@ -10,6 +10,7 @@ #define ELFCORE_ADDR_ERR (-2ULL) extern unsigned long long elfcorehdr_addr; +extern unsigned long long elfcorehdr_size; extern ssize_t copy_oldmem_page(unsigned long, char *, size_t, unsigned long, int); --- a/kernel/crash_dump.c +++ b/kernel/crash_dump.c @@ -20,8 +20,15 @@ unsigned long saved_max_pfn; unsigned long long elfcorehdr_addr = ELFCORE_ADDR_MAX; /* + * stores the size of elf header of crash image + */ +unsigned long long elfcorehdr_size; + +/* * elfcorehdr= specifies the location of elf core header stored by the crashed * kernel. This option will be passed by kexec loader to the capture kernel. + * + * Syntax: elfcorehdr=[size[KMG]@]offset[KMG] */ static int __init setup_elfcorehdr(char *arg) { @@ -29,6 +36,10 @@ static int __init setup_elfcorehdr(char if (!arg) return -EINVAL; elfcorehdr_addr = memparse(arg, &end); + if (*end == '@') { + elfcorehdr_size = elfcorehdr_addr; + elfcorehdr_addr = memparse(end + 1, &end); + } return end > arg ? 0 : -EINVAL; } early_param("elfcorehdr", setup_elfcorehdr); _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec