From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 20A05283FD4; Fri, 26 Jun 2026 00:51:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782435062; cv=none; b=MJ9qppf3VXdpkipvQ0yAVtwcSWIipR2JysrMuy7kIizjd7ASfxWWQSa5lk09qqnyGFv3QbqKLI0DvxvNlO8dF9XmZW0XrOa3h6Ow0N9uzClnDH7jvWUOF5t+PYBLwnVI5CAqz+lltz3VNIU9TM5Ig7C0+3M1Wt/KfYfPQvVmGoI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782435062; c=relaxed/simple; bh=UUNEW/3BM3oDz4zPKkzCZLrCik4vzpA79gZ+K/u0j9E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=GzCXC7T3+0yiEqZVtH/Jy47Cr+17NYAlcqJwxx+Ndzh2+u1fNA75ph8hqnHMsVNqX5IaqPJR7SJBunLPKp/0SGUvZ/zfbSyLmkAtEyC0bqHFhAqzNZ3cd+czLWyL2lpuSktqUEsx6Gr+jOkvjmK/txWcMlL0RvSXLo799Uke/HM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IVQeQK2W; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IVQeQK2W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DABE1F000E9; Fri, 26 Jun 2026 00:50:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782435060; bh=IOza8xsp2dv/+CoiTNhe/XVYthd1WQ3C2F501Mbqnn0=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=IVQeQK2WRT2tWquvOPKU7LhLwB+KrcnBI5JqNhdT/ps8dG0B7WLYRsUKAMoP6rKDI brB39UXVroZFetYvkvOMYLd0LFOx13wS1BXFGB3Zt78BcQYcD1QLJONBWKn8SeQHBj dPd2XJN80T+2KXbG82O0KaRfsHtV1DKGATKm+nPWoHBjSZ9mbuFWDJJKE/DV9BosrP oruhk+XrTcC4Av1ZXZeCUQG1O8RdWoGNYLYM2YEAlUFjUoTWiokLZSe8Nycu7fqRoO tzsWvtQKIuEw10+pGFKlmML2U49gANYa47kxTbsDY1JqM74eHWOIZ4ICd9n6/sa1in Vf1KljXWR3iZw== Message-ID: Date: Fri, 26 Jun 2026 01:50:55 +0100 Precedence: bulk X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 1/8] media: virtio: Add protocol To: Brian Daniels , Mauro Carvalho Chehab Cc: acourbot@google.com, adelva@google.com, aesteve@redhat.com, changyeon@google.com, daniel.almeida@collabora.com, eperezma@redhat.com, gnurou@gmail.com, gurchetansingh@google.com, hverkuil@xs4all.nl, jasowang@redhat.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, mst@redhat.com, nicolas.dufresne@collabora.com, virtualization@lists.linux.dev, xuanzhuo@linux.alibaba.com References: <20260625202412.2986772-1-briandaniels@google.com> From: Bryan O'Donoghue Content-Language: en-US Autocrypt: addr=bod@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 25/06/2026 21:24, Brian Daniels wrote: > I'm not an expert here, but taking a look at those files, the vast majority of > those reserved fields appear to be padding to ensure the struct has 64-bit > alignment, which matches the use here in virtio-media as well. > > virtio_pci appears to be the only device that explicitly states the > reserved bytes are for future extensions. Unless there's a good a reason to > expect a future use case where more space is needed, I would prefer to not add > more at this time. I'm querying why just the one though ? Why not say four ? Perhaps something you could address in your commit log. --- bod