Re: kexec, x86: Need a new e820 type support for kexec

[Baoquan He]

Hi Toshi,

Does this patch work for you?

There are things I am not sure. When jump to kexec/kdump kernel is this
PMEM still needed by system? And what's the difference between PRAM and
PMEM? I saw in kernel commit ec776ef6 it introduced E820_PRAM for the
non-standard protected e820 type, then in kernel commit ad5fb870 it
introduced E820_PMEM for ACPI 6.0 persistent memory types. While it
doesn't add complete support for E820_PMEM like E820_PRAM if I
understand it correctly. In this patch I simply pass E820_PMEM to kdump
kernel as E820_PRAM when it emerges since kernel can parse E820_PRAM
only in parse_memmap_one(), otherwise E820_PMEM has to be discarded or
need be passed as E820_RESERVED. What do you think about this, need
E820_PMEM be differentiated with E820_PRAM strictly? If yes, I think a
kernel patch need be posted to fix this. If not, this patch is enough
for supporting both of them in kexec.