linux-kernel - Re: [PATCH] mm/huge_memory: softleaf device private fixes in remove_migration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <b02a9217-f2d9-4005-b7ed-6f4198670ba3@kernel.org>
Date: Thu, 13 Nov 2025 08:32:16 +0100
From: "David Hildenbrand (Red Hat)" <david@...nel.org>
To: Balbir Singh <balbirs@...dia.com>, linux-mm@...ck.org
Cc: linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
 Lorenzo Stoakes <lorenzo.stoakes@...cle.com>, Zi Yan <ziy@...dia.com>,
 Baolin Wang <baolin.wang@...ux.alibaba.com>,
 "Liam R. Howlett" <Liam.Howlett@...cle.com>, Nico Pache <npache@...hat.com>,
 Ryan Roberts <ryan.roberts@....com>, Dev Jain <dev.jain@....com>,
 Barry Song <baohua@...nel.org>, Lance Yang <lance.yang@...ux.dev>
Subject: Re: [PATCH] mm/huge_memory: softleaf device private fixes in
 remove_migration_pmd()

On 13.11.25 06:03, Balbir Singh wrote:
> On 11/12/25 22:37, David Hildenbrand (Red Hat) wrote:
>> On 12.11.25 05:46, Balbir Singh wrote:
>>> commit a6ca2ba46390 ("mm: replace pmd_to_swp_entry() with softleaf_from_pmd()")
>>
>> So should this be squashed into Lorenzo patch, or incorporated in his series in case he has to resend?
>>
>>> does not work with device private THP entries. softleaf_is_migration_young()
>>> asserts that the entry be a migration entry, but in the current code, the
>>> entry might already be replaced by a device private entry by the time the
>>> check is made. The issue exists with commit
>>> 7385dbdbf841 ("mm/rmap: extend rmap and migration support device-private entries")
>>>
>>
>> Because this confuses me. If it's already a problem in the commit-to-go-upstream-first, it should be fixed in that commit?
>>
> 
> Not sure how to handle this, because that would break rebase of mm/mm-new
> or I'd have to send a replacement patch for the original patch from Lorenzo
> (which does not seem right).

Yes, to be expected. Maybe Andrew can figure out how do address the 
rebase, or we can give him a helping hand :)

> 
> I'll post a simpler patch, but it needs to be on top of the series

Agreed, thanks.

-- 
Cheers

David