[PATCH 06/12] kho: allow early-boot usage of the KHO radix tree

[Pratyush Yadav]

On Mon, May 11 2026, Mike Rapoport wrote:

> On Wed, Apr 29, 2026 at 03:39:08PM +0200, Pratyush Yadav wrote:
>> From: "Pratyush Yadav (Google)" <pratyush at kernel.org>
>> 
>> The KHO radix tree allocates memory for table pages from the buddy
>> allocator using get_zeroed_page(). This is not available in early boot
>> when memblock is still active.
>> 
>> Using the radix tree in early boot is useful for KHO to track metadata
>> about its memory. One such example is for tracking free blocks for
>> memory allocation when scratch runs out of space. This feature will be
>> added in the following commits.
>> 
>> Add kho_radix_{alloc,free}_node() which allocate and free the table
>> pages. They use slab_is_available() to decide which allocator to use.
>> While slab_is_available() indicates availability of the slab allocator,
>> it gets initialized right before buddy so it serves the same practical
>
>                            ^ after?

ACK, will fix.

>
>> purpose.
>> 
>> Signed-off-by: Pratyush Yadav (Google) <pratyush at kernel.org>
>> ---
>>  kernel/liveupdate/kexec_handover.c | 24 ++++++++++++++++++++++--
>>  1 file changed, 22 insertions(+), 2 deletions(-)

-- 
Regards,
Pratyush Yadav