linux-kernel - Re: [PATCH v4 13/13] x86/folio_zero

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: <20250616145007.GF1613376@noisy.programming.kicks-ass.net>
Date: Mon, 16 Jun 2025 16:50:07 +0200
From: Peter Zijlstra <peterz@...radead.org>
To: Dave Hansen <dave.hansen@...el.com>
Cc: Ankur Arora <ankur.a.arora@...cle.com>, linux-kernel@...r.kernel.org,
	linux-mm@...ck.org, x86@...nel.org, akpm@...ux-foundation.org,
	bp@...en8.de, dave.hansen@...ux.intel.com, hpa@...or.com,
	mingo@...hat.com, mjguzik@...il.com, luto@...nel.org,
	acme@...nel.org, namhyung@...nel.org, tglx@...utronix.de,
	willy@...radead.org, jon.grimm@....com, bharata@....com,
	raghavendra.kt@....com, boris.ostrovsky@...cle.com,
	konrad.wilk@...cle.com
Subject: Re: [PATCH v4 13/13] x86/folio_zero_user: Add multi-page clearing

On Mon, Jun 16, 2025 at 07:44:13AM -0700, Dave Hansen wrote:

> To me, that's deserving of an ARCH_HAS_FOO bit that we can set on the
> x86 side that then cajoles the core mm/ code to use the fancy new
> clear_pages_resched() implementation.

Note that we should only set this bit with either full or lazy
preemption selected. Haven't checked the patch-set to see if that
constraint is already taken care of.