[PATCH 5/5] kexec: X86: Pass memory ranges via e820 table instead of memmap= boot parameter

[Thomas Renninger]

On Friday, April 12, 2013 05:56:08 PM Zhang Yanfei wrote:
> 于 2013年04月11日 20:26, Thomas Renninger 写道:
> > Currently ranges are passed via kernel boot parameters:
> > memmap=exactmap memmap=X#Y memmap=
> > 
...
> > -	if (!(end - start))
> > -		return 0;
> > +	/*
> > +	 * Ignore usable memory ranges for kdump kernel smaller
> > +	 * than 100k to avoid too much ranges passed
> > +	 * Save the new ranges (exluding lower than 100k ranges) in tmp_map
> > +	 * and store the number of elements in tmp_map_ranges
> > +	 */
> > +	for (m = 0, i = 0; i < CRASH_MAX_MEMMAP_NR; i++) {
> > +		unsigned long startk, endk;
> > +		startk = (usable_mem[i].start/1024);
> > +		endk = ((usable_mem[i].end + 1)/1024);
> > +		if (!startk && !endk)
> > +			/* All regions traversed. */
> > +			break;
> > +
> > +		/* A region is not worth adding if region size < 100K. It eats
> > +		 * up precious command line length. */
> 
> Now you are passing the e820 table directly instead of the commandline, so
> does this comment make sense now?
Yes you are right, the comment is wrong.
It should more be like:
/*
A region is not worth adding if region size < 100K. e820 entries are 
restricted to 128 in kernel, with kdump we may have to pass the one or other
more and we want to try to stay at 128 max entries (from original table) as 
close as possible.
*/

Thanks,

      Thomas