Re: [PATCH 1/4] locking/atomic/x86: Silence intentional wrapping addition

From: Kees Cook <keescook@chromium.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Will Deacon <will@kernel.org>, Boqun Feng <boqun.feng@gmail.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
	Jakub Kicinski <kuba@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Andrew Morton <akpm@linux-foundation.org>,
	"David S. Miller" <davem@davemloft.net>,
	David Ahern <dsahern@kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Paolo Abeni <pabeni@redhat.com>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Uros Bizjak <ubizjak@gmail.com>,
	linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org,
	netdev@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH 1/4] locking/atomic/x86: Silence intentional wrapping addition
Date: Thu, 25 Apr 2024 10:19:24 -0700	[thread overview]
Message-ID: <202404251018.C12E9F23@keescook> (raw)
In-Reply-To: <ZiotNVLD3ek-9Lwj@FVFF77S0Q05N>

On Thu, Apr 25, 2024 at 11:15:17AM +0100, Mark Rutland wrote:
> To be clear, I dislike the function annotation because then it applies to
> *everything* within the function, which is overly broad and the intent becomes
> unclear. That makes it painful to refactor the code (since e.g. if we want to
> add another operation to the function which *should not* wrap, that gets
> silenced too).

Yeah, I find that a convincing argument for larger functions, but it
seemed to me that for these 1-line implementations it was okay. But
regardless, yup, no function-level annotation here.

> I'm happy with something that applies to specific types/variables or specific
> operations (which is what these patches do).

Thanks!

-- 
Kees Cook