linux-kernel - Re: [PATCH V14 1/6] mm: softdirty: Add pgtable_supports_soft

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: <45cd1637-54f6-4941-9670-7130aaf080f0@redhat.com>
Date: Thu, 18 Sep 2025 11:03:02 +0200
From: David Hildenbrand <david@...hat.com>
To: Chunyan Zhang <zhangchunyan@...as.ac.cn>,
 linux-riscv@...ts.infradead.org, devicetree@...r.kernel.org,
 linux-fsdevel@...r.kernel.org, linux-mm@...ck.org,
 linux-kernel@...r.kernel.org
Cc: Paul Walmsley <paul.walmsley@...ive.com>,
 Palmer Dabbelt <palmer@...belt.com>, Albert Ou <aou@...s.berkeley.edu>,
 Alexandre Ghiti <alex@...ti.fr>, Rob Herring <robh@...nel.org>,
 Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor@...nel.org>,
 Deepak Gupta <debug@...osinc.com>, Ved Shanbhogue <ved@...osinc.com>,
 Alexander Viro <viro@...iv.linux.org.uk>,
 Christian Brauner <brauner@...nel.org>, Jan Kara <jack@...e.cz>,
 Andrew Morton <akpm@...ux-foundation.org>, Peter Xu <peterx@...hat.com>,
 Arnd Bergmann <arnd@...db.de>, 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>,
 Axel Rasmussen <axelrasmussen@...gle.com>, Yuanchu Xie <yuanchu@...gle.com>,
 Chunyan Zhang <zhang.lyra@...il.com>
Subject: Re: [PATCH V14 1/6] mm: softdirty: Add pgtable_supports_soft_dirty()

On 18.09.25 10:37, Chunyan Zhang wrote:
> Some platforms can customize the PTE PMD entry soft-dirty bit making it
> unavailable even if the architecture provides the resource.
> 
> Add an API which architectures can define their specific implementations
> to detect if soft-dirty bit is available on which device the kernel is
> running.
> 
> This patch is removing "ifdef CONFIG_MEM_SOFT_DIRTY" in favor of
> pgtable_supports_soft_dirty() checks that defaults to
> IS_ENABLED(CONFIG_MEM_SOFT_DIRTY), if not overridden by
> the architecture, no change in behavior is expected.
> 
> We make sure to never set VM_SOFTDIRTY if !pgtable_supports_soft_dirty(),
> so we will never run into VM_SOFTDIRTY checks.
> 
> Acked-by: David Hildenbrand <david@...hat.com>
> Signed-off-by: Chunyan Zhang <zhangchunyan@...as.ac.cn>
> ---

[...]

>   mas_store_fail:
> diff --git a/mm/vma_exec.c b/mm/vma_exec.c
> index 922ee51747a6..a822fb73f4e2 100644
> --- a/mm/vma_exec.c
> +++ b/mm/vma_exec.c
> @@ -107,6 +107,7 @@ int relocate_vma_down(struct vm_area_struct *vma, unsigned long shift)
>   int create_init_stack_vma(struct mm_struct *mm, struct vm_area_struct **vmap,
>   			  unsigned long *top_mem_p)
>   {
> +	unsigned long flags  = VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP;

No need to resend because of this (probably can be fixed up when 
applying): there is a double space before the "="

-- 
Cheers

David / dhildenb