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 8161C377019; Tue, 23 Jun 2026 00:57:50 +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=1782176271; cv=none; b=YXw/U0HIx12Kyy7oqHVvNu6yScq1qDnnTTQuTP+BdIn75SgLl2OFbBcedADGlWbrTpl/e0ZgBcH8CRmoTLtGHfelssxE/lD/0ljY0ppfGcJqggki5Wp3SBorus6SYt/YdWmjWSJtxA15HhhKD0IihXNsIX1dNUJ91m0Y1JHG7L4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782176271; c=relaxed/simple; bh=m1g4xKHZr+EAT6GJjdEilXTeThpVvSQcrcQXopN3Il4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=WINWdsgBOUbe1DWpMoVWwfpIkVuxH/bwhEa48b0xAnRwVUHo6keC3CkggXPnq60InVl4NwrB3FQ+cHrQGbX2IW4iFVvwHOQ0/xbFbW6gM0cs3yIWQsGv8oXfvC9N8d+oOHjpqqVC/SwWzCZytmgyoPhFa7u+GcUketnQQxFDVSM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GtZY55KG; 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="GtZY55KG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06D931F000E9; Tue, 23 Jun 2026 00:57:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782176270; bh=3alYUOb6C/Wbd5vFlD2KNW62xIV+RJoXmu22bGohqYI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=GtZY55KGabENmhM5ryKwKJTdpNIC/x9joxVpX4SE5xhlx4YgavXU4kmtkQzpC/+TJ 7+71qLz9wPWp6IFiJSFzzRDGApBG6qqkuBaN9u1Iz+L8hj6VUPkjhJTySBigjkCXSI oq1MmZzfsnnpVTESIFfj4EYG/WcoaB1DvqaGek/9kQXa1rmddoWte3JNSFcy8VUwt0 bEibgPXpDEQ76rxsGcGrPnaEjuRSa2IYRXRVXP3N2yZ1k1iW3s9JjAvZzico/ZafKa Z6OIuyOkdUA00yEEr08dxHGZhjZVIC19Fv0h7dlUNoUlwq6dCJFTtU9PTkpKYc5iDi bigIevvK9iKIQ== Message-ID: <4b2078a0-9422-467b-b167-9a0b5444f18d@kernel.org> Date: Tue, 23 Jun 2026 01:57:35 +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: <20260622204343.1994418-1-briandaniels@google.com> <20260622204343.1994418-2-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: 8bit On 22/06/2026 21:43, Brian Daniels wrote: > + u32 __reserved; Knowing ~ nothing about virtio with ~ no experience of it I'll offer up a question/statement anyway. Aren't your reservations here a bit conservative ? Would you not be well advised to reserve a bit more space per other virtio protocols ? ➜ grep reserved ./include/uapi/linux/*.h | grep virtio ./include/uapi/linux/virtio_balloon.h: * __u8 reserved[6]; ./include/uapi/linux/virtio_balloon.h: * In other words, add explicit reserved fields to align field and ./include/uapi/linux/virtio_blk.h: __u8 reserved[38]; ./include/uapi/linux/virtio_blk.h: __u8 reserved[56]; ./include/uapi/linux/virtio_config.h: * VIRTIO_TRANSPORT_F_END are reserved for the transport ./include/uapi/linux/virtio_crypto.h: __le32 reserved; ./include/uapi/linux/virtio_i2c.h: * Copyright (c) 2021 Intel Corporation. All rights reserved. ./include/uapi/linux/virtio_input.h: __u8 reserved[5]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[3]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[3]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[3]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[4]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[8]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[4]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[3]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[64]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved[3]; ./include/uapi/linux/virtio_iommu.h: __u8 reserved2[4]; ./include/uapi/linux/virtio_net.h: __le16 reserved[4]; ./include/uapi/linux/virtio_net.h: __le16 reserved; ./include/uapi/linux/virtio_net.h: __le16 reserved[3]; ./include/uapi/linux/virtio_net.h: __u8 reserved; ./include/uapi/linux/virtio_net.h: __le16 reserved1; ./include/uapi/linux/virtio_pcidev.h: * @VIRTIO_PCIDEV_OP_RESERVED: reserved to catch errors ./include/uapi/linux/virtio_pcidev.h: * @reserved: reserved ./include/uapi/linux/virtio_pcidev.h: __u16 reserved; ./include/uapi/linux/virtio_pci.h: * 2-65535 - reserved ./include/uapi/linux/virtio_pci.h: /* Unused, reserved for future extensions. */ ./include/uapi/linux/virtio_pci.h: __u8 reserved1[12]; ./include/uapi/linux/virtio_pci.h: /* Unused, reserved for future extensions. */ ./include/uapi/linux/virtio_pci.h: __u8 reserved2[4]; ./include/uapi/linux/virtio_pci.h: __u8 reserved[7]; ./include/uapi/linux/virtio_pci.h: __u8 reserved[6]; ./include/uapi/linux/virtio_pci.h: __u8 reserved[6]; ./include/uapi/linux/virtio_pci.h: __u8 reserved[2]; ./include/uapi/linux/virtio_pci.h: __u8 reserved[7]; ./include/uapi/linux/virtio_pci.h: __u8 reserved[7]; ./include/uapi/linux/virtio_pci.h: __u8 reserved; ./include/uapi/linux/virtio_pci.h: __le32 reserved; ./include/uapi/linux/virtio_pci.h: __u8 reserved[6]; ./include/uapi/linux/virtio_pci.h: __le32 reserved; ./include/uapi/linux/virtio_pci.h: __le32 reserved; ./include/uapi/linux/virtio_pci.h: __le32 reserved; ./include/uapi/linux/virtio_pci.h: __u8 reserved[7]; ./include/uapi/linux/virtio_rtc.h: * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved. ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[7]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[5]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[5]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[5]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[7]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[7]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[5]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[5]; ./include/uapi/linux/virtio_rtc.h: __u8 reserved[6]; ./include/uapi/linux/virtio_spi.h: * Copyright (C) 2025 Qualcomm Innovation Center, Inc. All rights reserved. ./include/uapi/linux/virtio_spi.h: * other bits are reserved as 0, 1-bit transfer is always supported. ./include/uapi/linux/virtio_spi.h: * other bits are reserved as 0, 1-bit transfer is always supported. ./include/uapi/linux/virtio_spi.h: * @reserved: for future use. ./include/uapi/linux/virtio_spi.h: __u8 reserved[3];+ u32 __reserved; --- bod