On 28/06/20 7:44 am, piliu wrote:

Hi Hari,

Hi Pingfan,

After a quick through for this series, I have a few question/comment on
this patch for the time being. Pls see comment inline.

On 06/27/2020 03:05 AM, Hari Bathini wrote:

quoted

crashkernel region could have an overlap with special memory regions
like  opal, rtas, tce-table & such. These regions are referred to as
exclude memory ranges. Setup this ranges during image probe in order
to avoid them while finding the buffer for different kdump segments.

[...]

quoted

+	/*
+	 * Use the locate_mem_hole logic in kexec_add_buffer() for regular
+	 * kexec_file_load syscall
+	 */
+	if (kbuf->image->type != KEXEC_TYPE_CRASH)
+		return 0;

Can the ranges overlap [crashk_res.start, crashk_res.end]?  Otherwise
there is no requirement for @exclude_ranges.

The ranges like rtas, opal are loaded by f/w. They almost always overlap with
crashkernel region. So, @exclude_ranges is required to support kdump.

I guess you have a design for future. If not true, then it is better to
fold the condition "if (kbuf->image->type != KEXEC_TYPE_CRASH)" into the
caller and rename this function to better distinguish use cases between
kexec and kdump

Yeah, this condition will be folded. I have a follow-up patch for that explaining
why kexec case should also be folded. Will try to add that to this series for v2.

Thanks
Hari