On 2011-10-18 15:51, Wen Congyang wrote:
> On 10/18/2011 06:28 PM, Jan Kiszka wrote:
>> On 2011-10-18 11:43, Wen Congyang wrote:
>>> At 10/18/2011 04:36 PM, Jan Kiszka Write:
>>>> On 2011-10-18 10:34, Richard W.M. Jones wrote:
>>>>
>>>> Yeah, I see. Could also be solved via gdb scripts, but crash is already
>>>> there.
>>>>
>>>> But let's see if the formats actually differ. In the end, crash is just
>>>> parsing the same information that also gdb sees.
>>>
>>> I think the format can be similar with diskdump/kdump/netdump:
>>>
>>> dump_header: 1 block
>>> sub header: n blocks(n is stored in dump_header)
>>> bitmap: m blocks(2m is stored in dump_header)
>>> dumpable bitmap: m blocks
>>> memory data(We can know whether a page is stored in the core by bitmap and
>>> dumpable bitmap)
>>>
>>> The format of dump header(It's like kdump/diskdump):
>>> struct disk_dump_header {
>>> char signature[SIG_LEN]; /* = "QEMU " */
>>> int header_version; /* Dump header version */
>>> struct new_utsname utsname; /* copy of system_utsname */
>>> struct timeval timestamp; /* Time stamp */
>>> unsigned int status;
>>> int block_size; /* Size of a block in byte */
>>> int sub_hdr_size; /* Size of arch dependent
>>> header in blocks */
>>> unsigned int bitmap_blocks; /* Size of Memory bitmap in
>>> block */
>>> unsigned int max_mapnr; /* = max_mapnr */
>>> unsigned int total_ram_blocks;/* Number of blocks should be
>>> written */
>>> unsigned int device_blocks; /* Number of total blocks in
>>> * the dump device */
>>> unsigned int written_blocks; /* Number of written blocks */
>>> unsigned int current_cpu; /* CPU# which handles dump */
>>> int nr_cpus; /* Number of CPUs */
>>> };
>>>
>>> The sub header can contains all registers's value on each vcpu, and other
>>> information,
>>> for example:
>>> struct qemu_sub_header {
>>> unsigned long start_pfn;
>>> unsigned long end_pfn;
>>> off_t offset_note;
>>> unsigned long size_note;
>>> };
>>
>> So is this a standard format or only "similar" to something? Which tools
>> will understand it out-of-the-box? If it's not standard, why?
>
> Only similar to something, and we can add a little codes into crash to
> support such format.
>
> If you have a better format, please tell me.
The format crash already processes? What do you need in addition? That
should be discussed first, not the format details.
Jan
--
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux
