From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8B94F33F8C1; Tue, 21 Oct 2025 14:46:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761058014; cv=none; b=UXpDLVnXQrkItiN7IAhyRQXjj53+qUgW0PpxJB1EwqEkjDjovtwSVDFDK3RH1+dG9zByA9kCPUl/adksqcoTc0bPPg3yNl4p0MhXRFCCpAkVUscjraE3kkP4cWVrCUZ3IzdLfuuq5j34delNSBy60LExbJkEgGpLZQlY8EwcNc0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761058014; c=relaxed/simple; bh=6LafgLKl/jr0eBL0blTksKXhLI26P06pH8jkNqckT64=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=jV/w3F9oBndSpCMWzUhDdBQQ6H2Ea2wZD7gF/KqnpIndHdwu8zF5RxkWrl/zkRJTOlpQJeUqN9sjd5JN2MZ8WlHGLDVJla7XXKpRMI7VtHzXc3DpPZMaw/OViQE7Ica2NhVxi/Fv8iI1s4NvASGY2ABcoBq7DsxpUm7NkhZLPdw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lvVDD/E9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="lvVDD/E9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5D937C4CEF7; Tue, 21 Oct 2025 14:46:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761058014; bh=6LafgLKl/jr0eBL0blTksKXhLI26P06pH8jkNqckT64=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=lvVDD/E9awuwjfEgIYXiDpeMidmlXzdZX68hL/vT63pqXw9Of+yqCHV4N4zaJpp+B KnrZI+LCUJbeJqMyJmUTEb9pvjaZ5DN5Z7tfZuGfiiE0RdbhaFiiCZBl+vEvqJ1f72 9OO2CDvSmcw//rutcCH0WHaWTmChVsAmc9ILnPDaQ68ZJUnXv0O4ZfHTzjDENwxnVd 4/j9PKcwt/eJlardiZRGzIisCs+dmn8qLQGwgKVkyZ7d/G+s0EiczkSQczs195TY/Z SPPFJCInizx14f2f08zedDwmhSKIZq95qZ9J20oaK4HclWl0khME8Tu1+E65Z7ANPt h+4xa/Rbk39ZQ== Message-ID: <54328318-c235-413a-a069-5ea93f1dcb2b@kernel.org> Date: Tue, 21 Oct 2025 16:46:48 +0200 Precedence: bulk X-Mailing-List: rust-for-linux@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] rust: add udelay() function To: Miguel Ojeda Cc: FUJITA Tomonori , aliceryhl@google.com, daniel.almeida@collabora.com, a.hindborg@kernel.org, alex.gaynor@gmail.com, ojeda@kernel.org, anna-maria@linutronix.de, bjorn3_gh@protonmail.com, boqun.feng@gmail.com, frederic@kernel.org, gary@garyguo.net, jstultz@google.com, linux-kernel@vger.kernel.org, lossin@kernel.org, lyude@redhat.com, rust-for-linux@vger.kernel.org, sboyd@kernel.org, tglx@linutronix.de, tmgross@umich.edu, Greg Kroah-Hartman References: <20251021071146.2357069-1-fujita.tomonori@gmail.com> <20251021071146.2357069-2-fujita.tomonori@gmail.com> From: Danilo Krummrich Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/21/25 4:39 PM, Miguel Ojeda wrote: > Now, for runtime values, since random drivers will call this with > possibly computed values based on who knows what, a warn once may be > too much. A debug assert instead would be less risky if it makes > people more comfortable. Exactly, also consider that MAX_UDELAY_MS depends on the architecture and HZ. Given that we'd have a WARN() for any value passed that is > MAX_UDELAY_MS, and given that WARN() is considered a vulnerability if hit (Greg, please correct me if that's wrong), this would literally become a vulnerability generator. :)