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Date: Wed, 1 May 2024 19:23:23 +0200
From: Erick Archer <erick.archer@outlook.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Erick Archer <erick.archer@outlook.com>, Ingo Molnar <mingo@redhat.com>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Namhyung Kim <namhyung@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>, Ian Rogers <irogers@google.com>,
	Adrian Hunter <adrian.hunter@intel.com>,
	"Liang, Kan" <kan.liang@linux.intel.com>,
	Kees Cook <keescook@chromium.org>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	Justin Stitt <justinstitt@google.com>,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH] perf/ring_buffer: Prefer struct_size over open coded
 arithmetic
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On Tue, Apr 30, 2024 at 11:15:04AM +0200, Peter Zijlstra wrote:
> On Mon, Apr 29, 2024 at 07:40:58PM +0200, Erick Archer wrote:
> > This is an effort to get rid of all multiplications from allocation
> > functions in order to prevent integer overflows [1][2].
> 
> So personally I detest struct_size() because I can never remember wtf it
> does, whereas the code it replaces is simple and straight forward :/

Ok, I accept what you say. Anyway, I think it's a matter of preference ;)

If I prepare a patch with the changes suggested by Kees to gain coverage
of the __counted_by attribute, will it have a chance of being accepted?

Are there any guidelines related to this attribute, such as in the case
of the struct_size() helper?

Regards,
Erick