linux-kernel - Re: [RFC PATCH v1 3/6] mm: Avoid calling page allocator from apply_to_page

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: <fbscxpcwnqu7fblvzzngvgop2n5upal2wdlqn7k2rsbswdmna6@xiyhbt5j3web>
Date: Fri, 30 May 2025 15:08:59 -0400
From: "Liam R. Howlett" <Liam.Howlett@...cle.com>
To: Ryan Roberts <ryan.roberts@....com>
Cc: Catalin Marinas <catalin.marinas@....com>, Will Deacon <will@...nel.org>,
        Madhavan Srinivasan <maddy@...ux.ibm.com>,
        Michael Ellerman <mpe@...erman.id.au>,
        Nicholas Piggin <npiggin@...il.com>,
        Christophe Leroy <christophe.leroy@...roup.eu>,
        "David S. Miller" <davem@...emloft.net>,
        Andreas Larsson <andreas@...sler.com>, Juergen Gross <jgross@...e.com>,
        Ajay Kaher <ajay.kaher@...adcom.com>,
        Alexey Makhalov <alexey.makhalov@...adcom.com>,
        Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>,
        Borislav Petkov <bp@...en8.de>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        "H. Peter Anvin" <hpa@...or.com>,
        Boris Ostrovsky <boris.ostrovsky@...cle.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@...nel.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Peter Zijlstra <peterz@...radead.org>, Arnd Bergmann <arnd@...db.de>,
        David Hildenbrand <david@...hat.com>,
        Lorenzo Stoakes <lorenzo.stoakes@...cle.com>,
        Vlastimil Babka <vbabka@...e.cz>, Mike Rapoport <rppt@...nel.org>,
        Suren Baghdasaryan <surenb@...gle.com>, Michal Hocko <mhocko@...e.com>,
        Alexei Starovoitov <ast@...nel.org>,
        Andrey Ryabinin <ryabinin.a.a@...il.com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linuxppc-dev@...ts.ozlabs.org, sparclinux@...r.kernel.org,
        virtualization@...ts.linux.dev, xen-devel@...ts.xenproject.org,
        linux-mm@...ck.org
Subject: Re: [RFC PATCH v1 3/6] mm: Avoid calling page allocator from
 apply_to_page_range()

* Ryan Roberts <ryan.roberts@....com> [250530 12:50]:
...

> > 
> > 
> > These wrappers are terrible for readability and annoying for argument
> > lists too.
> 
> Agreed.
> 
> > 
> > Could we do something like the pgtbl_mod_mask or zap_details and pass
> > through a struct or one unsigned int for create and lazy_mmu?
> 
> Or just create some enum flags?
> 
> > 
> > At least we'd have better self-documenting code in the wrappers.. and if
> > we ever need a third boolean, we could avoid multiplying the wrappers
> > again.
> > 
> > WDYT?
> 
> I'm happy with either approach. I was expecting more constination about the idea
> of being able to disable lazy mode though, so perhaps I'll wait and see if any
> arrives. If it doesn't... flags?

Yes, that works as well.  Please use pmd_flags or anything more
descriptive than just 'flags' :)

I wonder which approach is best in asm instructions and self-documenting
code.

Regards,
Liam