linux-kernel - Re: [PATCH v3 22/22] mm/mshare: charge fault handling allocations to the mshare owner

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Message-ID: <a0238ff1-3ca2-4f0b-8452-26584b531724@redhat.com>
Date: Mon, 8 Sep 2025 20:50:00 +0200
From: David Hildenbrand <david@...hat.com>
To: Anthony Yznaga <anthony.yznaga@...cle.com>, linux-mm@...ck.org
Cc: akpm@...ux-foundation.org, andreyknvl@...il.com, arnd@...db.de,
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Subject: Re: [PATCH v3 22/22] mm/mshare: charge fault handling allocations to
 the mshare owner

On 20.08.25 03:04, Anthony Yznaga wrote:
> When handling a fault in an mshare range, redirect charges for page
> tables and other allocations to the mshare owner rather than the
> current task.
> 

That looks rather weird. I would have thought there would be an easy way 
to query the mshare owner for a given mshare mapping, and if the current 
MM corresponds to that owner you know that you are running in the owner 
context.

Of course, we could have a helper like is_mshare_owner(mapping, current) 
or sth like that.


-- 
Cheers

David / dhildenb