[PATCH v2 1/8] makedumpfile: Add '--config' option to specify filterconfig file.
tachibana at mxm.nes.nec.co.jp
tachibana at mxm.nes.nec.co.jp
Mon May 23 05:09:00 EDT 2011
Hi Mahesh
On 2011/05/18 01:30:07 +0530, Mahesh J Salgaonkar <mahesh at linux.vnet.ibm.com> wrote:
> From: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>
>
> This patch adds '--config' option to specify config file that contains filter
> commands to filter out desired kernel data and it's members.
>
> Updated makedumpfile man page with '--config' option info.
>
> Signed-off-by: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>
> Signed-off-by: Prerna Saxena <prerna at linux.vnet.ibm.com>
> ---
>
> makedumpfile.8 | 20 +++++++++++++++++++-
> makedumpfile.c | 17 +++++++++++++++++
> makedumpfile.h | 7 +++++++
> 3 files changed, 43 insertions(+), 1 deletions(-)
>
> diff --git a/makedumpfile.8 b/makedumpfile.8
> index 4a0271d..a1aaa3e 100644
> --- a/makedumpfile.8
> +++ b/makedumpfile.8
> @@ -6,6 +6,8 @@ makedumpfile \- make a small dumpfile of kdump
> .br
> \fBmakedumpfile\fR \-F [\fIOPTION\fR] [\-x \fIVMLINUX\fR|\-i \fIVMCOREINFO\fR] \fIVMCORE\fR
> .br
> +\fBmakedumpfile\fR [\fIOPTION\fR] \-x \fIVMLINUX\fR \-\-config \fIFILTERCONFIGFILE\fR \fIVMCORE\fR \fIDUMPFILE\fR
> +.br
> \fBmakedumpfile\fR \-R \fIDUMPFILE\fR
> .br
> \fBmakedumpfile\fR \-\-split [\fIOPTION\fR] [\-x \fIVMLINUX\fR|\-i \fIVMCOREINFO\fR] \fIVMCORE\fR \fIDUMPFILE1\fR \fI
DUMPFILE2\fR [\fIDUMPFILE3\fR ..]
> @@ -55,6 +57,15 @@ compression support. The ELF format is readable with GDB and the crash utility.
> If a user wants to use GDB, \fIDUMPFILE\fR format has to be explicitly
> specified to be the ELF format.
> .PP
> +Apart from the exclusion of unnecessary pages mentioned above, makedumpfile
> +allows user to filter out targeted kernel data. The filter config file can
> +be used to specify kernel/module symbols and its members that need to be
> +filtered out through the erase command syntax. makedumpfile reads the filter
> +config and builds the list of memory addresses and its sizes after processing
> +filter commands. The memory locations that require to be filtered out are
> +then poisoned with character 'X' (58 in Hex). Refer to \fBfilter.conf(8)\fR
> +for file format.
> +.PP
> To analyze the first kernel's memory usage, makedumpfile can refer to
> \fIVMCOREINFO\fR instead of \fIVMLINUX\fR. \fIVMCOREINFO\fR contains the first
> kernel's information (structure size, field offset, etc.), and \fIVMCOREINFO\fR
> @@ -232,6 +243,13 @@ specified.
> # makedumpfile \-g vmcoreinfo \-x vmlinux
>
> .TP
> +\fB\-\-config\fR \fIFILTERCONFIGFILE\fR
> +Used in conjunction with \-x \fIVMLINUX\fR option, to specify the filter
> +config file \fIFILTERCONFIGFILE\fR that contains erase commands to filter out
> +desired kernel data from vmcore while creating \fIDUMPFILE\fR. For filter
> +command syntax please refer to \fBfilter.conf(8)\fR.
> +
> +.TP
> \fB\-F\fR
> Output the dump data in the flattened format to the standard output for
> transporting the dump data by SSH.
> @@ -482,5 +500,5 @@ Written by Masaki Tachibana, and Ken'ichi Ohmichi.
>
> .SH SEE ALSO
> .PP
> -crash(8), gdb(1), kexec(8)
> +crash(8), gdb(1), kexec(8), filter.conf(8)
>
> diff --git a/makedumpfile.c b/makedumpfile.c
> index 7d0c663..f136eba 100644
> --- a/makedumpfile.c
> +++ b/makedumpfile.c
> @@ -636,6 +636,11 @@ print_usage(void)
> MSG(" Creating DUMPFILE:\n");
> MSG(" # makedumpfile [-c|-E] [-d DL] [-x VMLINUX|-i VMCOREINFO] VMCORE DUMPFILE\n");
> MSG("\n");
> + MSG(" Creating DUMPFILE with filtered kernel data specified through filter config\n");
> + MSG(" file:\n");
> + MSG(" # makedumpfile [-c|-E] [-d DL] -x VMLINUX --config FILTERCONFIGFILE VMCORE\n");
> + MSG(" DUMPFILE\n");
> + MSG("\n");
> MSG(" Outputting the dump data in the flattened format to the standard output:\n");
> MSG(" # makedumpfile -F [-c|-E] [-d DL] [-x VMLINUX|-i VMCOREINFO] VMCORE\n");
> MSG("\n");
> @@ -714,6 +719,11 @@ print_usage(void)
> MSG(" other system that is running the same first kernel. [-x VMLINUX] must\n");
> MSG(" be specified.\n");
> MSG("\n");
> + MSG(" [--config FILTERCONFIGFILE]:\n");
> + MSG(" Used in conjunction with -x VMLINUX option, to specify the filter config\n");
> + MSG(" file that contains filter commands to filter out desired kernel data\n");
> + MSG(" from vmcore while creating DUMPFILE.\n");
> + MSG("\n");
> MSG(" [-F]:\n");
> MSG(" Output the dump data in the flattened format to the standard output\n");
> MSG(" for transporting the dump data by SSH.\n");
> @@ -7729,6 +7739,9 @@ check_param_for_creating_dumpfile(int argc, char *argv[])
> if (info->flag_flatten && info->flag_split)
> return FALSE;
>
> + if (info->name_filterconfig && !info->name_vmlinux)
> + return FALSE;
A new option '--config makedumpfile.conf' always needs an option
'-x debug_info_file', doesn't it?
Once I heard that a debug_info file(i.e. vmlinux) was too large
to be included in 2nd kernel's initrd.
So instead of a debug_info_file, small text files generated by
'-g debug_info_file' were introduced.
Now a debug information is read from /proc/vmcore.
Do you want to use '--config' while 2nd kernel is running?
But I think it's impossible on usual distributers' environment, because
vmlinux is not included in 2nd kernel's initrd.
So I suppose you use this option as follows:
1.Panic occurs.
2.2nd kernel is activated.
3.makedumpfile makes a dump file from /proc/vmcore without '--config'.
4.1st kernel is reactivated.
5.makedumpfile makes a masked dump file from the above dump file
with '--config'.
Am I right?
Thanks
tachibana
> +
> if ((argc == optind + 2) && !info->flag_flatten
> && !info->flag_split) {
> /*
> @@ -7821,6 +7834,7 @@ static struct option longopts[] = {
> {"message-level", required_argument, NULL, 'm'},
> {"vtop", required_argument, NULL, 'V'},
> {"dump-dmesg", no_argument, NULL, 'M'},
> + {"config", required_argument, NULL, 'C'},
> {"help", no_argument, NULL, 'h'},
> {0, 0, 0, 0}
> };
> @@ -7851,6 +7865,9 @@ main(int argc, char *argv[])
> case 'b':
> info->block_order = atoi(optarg);
> break;
> + case 'C':
> + info->name_filterconfig = optarg;
> + break;
> case 'c':
> info->flag_compress = 1;
> break;
> diff --git a/makedumpfile.h b/makedumpfile.h
> index 4ec77b7..e037f12 100644
> --- a/makedumpfile.h
> +++ b/makedumpfile.h
> @@ -888,6 +888,13 @@ struct DumpInfo {
> unsigned long vmemmap_end;
>
> /*
> + * Filter config file containing filter commands to filter out kernel
> + * data from vmcore.
> + */
> + char *name_filterconfig;
> + FILE *file_filterconfig;
> +
> + /*
> * diskdimp info:
> */
> int block_order;
>
>
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