When we walk through iomem resources by calling walk_iomem_res_desc(),
the values of the function parameter may be modified in the while loop
of __walk_iomem_res_desc(), which will cause us to not get the desired
result in some cases.
At present, it only restores the original value of res->end,
E820 reserved ranges is useful in kdump kernel, we have added this in
kexec-tools code.
One reason is PCI mmconf (extended mode) requires reserved region
otherwise it falls back to legacy mode.
When AMD SME kdump support, it needs to map dmi table area as unencrypted.
For normal boot, these
E820 reserved ranges is useful in kdump kernel, we have added this in
kexec-tools code.
One reason is PCI mmconf (extended mode) requires reserved region otherwise
it falls back to legacy mode.
Furthermore, when AMD SME kdump support, it needs to map dmi table area as
unencrypted. For normal
kdump uses walk_iomem_res_desc() to iterate io resources, then adds matched
desc to e820 table for kdump kernel.
But IORES_DESC_NONE resource type includes several different e820 types,
we need add exact e820 type to kdump kernel e820 table, thus it also needs
an extra checking in
