[RFC PATCH 0/2] memblock: keep reserve_mem regions out of KHO bootmem
Jose A. Perez de Azpillaga
azpijr at gmail.com
Thu Oct 22 13:16:01 PDT 2026
On 10/22/26 3:37 PM, Pratyush Yadav wrote:
> On Wed, Oct 21 2026, Jose A. Perez de Azpillaga wrote:
>
>> On a KHO boot, a reserve_mem= region that can't be revived (new name,
>> size or alignment) can be allocated from KHO bootmem, which the next
>> kernel boots out of. With CONFIG_KEXEC_HANDOVER_DEBUG preserving it
>> fails; without it, the next kernel's memmap ends up on top of it.
> What's your use-case? Why are you adding new reserve_mem regions after
> cold boot? I'd rather avoid making purely theoretical fixes.
I don't have one, I found it through the TODO. a different reserve_mem=
in the cmdline passed to kexec is enough to hit it.
if it isn't meant to work across a live update, would you rather have
reserve_mem() fail on KHO boot when it can't revive the region?
--
cheers,
jose a. p-a
More information about the kexec
mailing list