linux-kernel - Re: [PATCH v5 09/16] kexec: enable KHO support for memory preservation

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Message-ID: <Z_agP1ohC3sVZrM7@kernel.org>
Date: Wed, 9 Apr 2025 19:28:47 +0300
From: Mike Rapoport <rppt@...nel.org>
To: Jason Gunthorpe <jgg@...dia.com>
Cc: Pratyush Yadav <ptyadav@...zon.de>,
	Changyuan Lyu <changyuanl@...gle.com>, linux-kernel@...r.kernel.org,
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Subject: Re: [PATCH v5 09/16] kexec: enable KHO support for memory
 preservation

On Mon, Apr 07, 2025 at 11:16:26AM -0300, Jason Gunthorpe wrote:
> On Sun, Apr 06, 2025 at 07:11:14PM +0300, Mike Rapoport wrote:
> 
> KHO needs to provide a way to give back an allocated struct page/folio
> that can be freed back to the buddy alloactor, of the proper
> order. Whatever you call that function it belongs to KHO as it is
> KHO's primary responsibility to manage the buddy allocator and the
> struct pages.

If order is only important for freeing memory back to page allocator, you
don't really need it. Freeing contiguous power-of-two number of pages with
proper alignment will give the same result, just a tad slower.
 
> Jason
> 

-- 
Sincerely yours,
Mike.