Re: [PATCH v12 00/16] Direct Map Removal Support for guest_memfd

From: Takahiro Itazuri <itazur@amazon.com>
To: <seanjc@google.com>, <ljs@kernel.org>
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Subject: Re: [PATCH v12 00/16] Direct Map Removal Support for guest_memfd
Date: Wed, 6 May 2026 08:07:52 +0000	[thread overview]
Message-ID: <20260506080753.14517-1-itazur@amazon.com> (raw)
In-Reply-To: <aeennZlV60k81OBf@google.com>

Hi Lorenzo and Sean,

Apologies for the delayed reply — Nikita is leaving Amazon, and I'm
taking over this series going forward. Thanks for your patience.

On Tue, Apr 21, 2026 at 01:40:00PM +0000, Lorenzo Stoakes wrote:
> Hm, given this touches a fair bit of mm, I wonder if we shouldn't try to do this
> through the mm tree?

On Tue, Apr 21, 2026 at 04:36:00PM +0000, Sean Christopherson wrote:
> Yeah, when the time comes, the mm pieces definitely need to go through the mm
> tree.  Ideally, I think this would be merged in two separate parts, with all mm
> changes going through the mm tree, and then the KVM changes through the KVM tree
> using a stable topic branch/tag from Andrew.

Thanks for the guidance. The split makes sense to me; I'm planning to
follow this approach with patches 1-6 (mm) going through the mm tree
and patches 7-16 (KVM) through the KVM tree on top of a stable
branch/tag from mm. I'll confirm the exact boundary and coordination
details as I prepare the repost.

On Tue, Apr 21, 2026 at 01:40:00PM +0000, Lorenzo Stoakes wrote:
> In any case, we definitely need a rebase on something not-next :) if not mm then
> Linus's tree at least maybe?
>
> I'm seeing a lot of conflicts against mm-unstable, it can't b4 shazam even patch
> 1 and in Linus's tree it's failing at an mm patch (mm: introduce
> AS_NO_DIRECT_MAP).

I'll rebase onto v7.1-rc1 and resolve the conflicts as part of the split.

Takahiro