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Date: Tue, 2 Dec 2025 08:59:07 -0800
From: Kees Cook <kees@kernel.org>
To: Ryan Roberts <ryan.roberts@arm.com>
Cc: Ard Biesheuvel <ardb+git@google.com>, Will Deacon <will@kernel.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Jeremy Linton <jeremy.linton@arm.com>,
	Catalin Marinas <Catalin.Marinas@arm.com>,
	Mark Rutland <mark.rutland@arm.com>,
	"Jason A . Donenfeld" <Jason@zx2c4.com>,
	linux-hardening@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC PATCH v1 0/2] Fix bugs and performance of kstack offset
 randomisation
Message-ID: <202512020858.8BD22F486@keescook>
References: <20251127105958.2427758-1-ryan.roberts@arm.com>
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In-Reply-To: <20251127105958.2427758-1-ryan.roberts@arm.com>

On Thu, Nov 27, 2025 at 10:59:54AM +0000, Ryan Roberts wrote:
> As I reported at [1], kstack offset randomisation suffers from a couple of bugs
> and, on arm64 at least, the performance is poor. This series attempts to fix
> both; patch 1 provides back-portable fixes for the functional bugs. Patch 2
> proposes a performance improvement approach.

Just to chime in -- this looks really good to me! Universally improved
performance, reduced complexity, and better randomness. :) I'm looking
forward to v2!

-Kees

-- 
Kees Cook