Re: [Fastboot] Re: Announce: dumpfs v0.01 - common RAS output API

Martin J. Bligh
2004-07-28T15:23:48Z

>> > Does anyone have a proof of concept implementation? I have been able to find
>>
>> Yes, Hari has a nice POC implementation - it might make sense for him to post
>> it rightaway for you to take a look. Basically, in addition to hmem (oldmem),
>> the upcoming kernel exports an ELF core view of the saved register and memory
>> state of the previous kernel as /proc/vmcore.prev (remember your suggestion
>> of using an ELF core file format for dump ?), so one can use cp or scp to
>> save the core dump to disk. He has a quick demo, where he uses gdb (unmodified)
>> to open the dump and show a stack trace of the dumping cpu.
>
> Yes I would like to look at that.
>
> I am tempted to suggest the data buffer with the registers and memory
> actually be in ELF format with virtual address representing where the
> data was in memory, and the physical addresses reporting where the
> data actually is in memory now. Then we could just grab everything
> with /dev/mem..
>
> But I don't know how much of pain this would be.

/dev/mem expects mem_map to be there, the size of which would easily
blow away the reserved section. /dev/oldmem (or whatever we call it)
is just a magic copy that does a kmap-like operation to get at pages
without a struct page.

M.