linux-kernel - Re: [PATCH v1 0/2] mm/huge_memory: don't mark refcounted pages special in vmf_insert_folio

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: <b80b62dc-76b9-4b3b-b980-7fa3584c9762@redhat.com>
Date: Tue, 3 Jun 2025 23:36:28 +0200
From: David Hildenbrand <david@...hat.com>
To: linux-kernel@...r.kernel.org
Cc: linux-mm@...ck.org, nvdimm@...ts.linux.dev, linux-cxl@...r.kernel.org,
 Andrew Morton <akpm@...ux-foundation.org>,
 Alistair Popple <apopple@...dia.com>,
 Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
 "Liam R. Howlett" <Liam.Howlett@...cle.com>, Vlastimil Babka
 <vbabka@...e.cz>, Mike Rapoport <rppt@...nel.org>,
 Suren Baghdasaryan <surenb@...gle.com>, Michal Hocko <mhocko@...e.com>,
 Zi Yan <ziy@...dia.com>, Baolin Wang <baolin.wang@...ux.alibaba.com>,
 Nico Pache <npache@...hat.com>, Ryan Roberts <ryan.roberts@....com>,
 Dev Jain <dev.jain@....com>, Dan Williams <dan.j.williams@...el.com>
Subject: Re: [PATCH v1 0/2] mm/huge_memory: don't mark refcounted pages
 special in vmf_insert_folio_*()

On 03.06.25 23:16, David Hildenbrand wrote:
> Based on Linus' master.
> 
> While working on improving vm_normal_page() and friends, I stumbled
> over this issues: refcounted "normal" pages must not be marked
> using pmd_special() / pud_special().
> 
> Fortunately, so far there doesn't seem to be serious damage.
> 
> This is only compile-tested so far. Still looking for an easy way to test
> PMD/PUD mappings with DAX. Any tests I can easily run?

... aaaand I should have waited for the cross compiles.

s390x and loongarch are not happy about pud_mkhuge() and pfn_pud().

Need to fence folio_mk_pud() by CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD.

-- 
Cheers,

David / dhildenb