Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Igor Skalkin <igor375@gmail.com>
To:     virtualization@lists.linux-foundation.org, luiz.dentz@gmail.com,
        mst@redhat.com
Cc:     marcel@holtmann.org, johan.hedberg@gmail.com, jasowang@redhat.com,
        linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org,
        Igor Skalkin <Igor.Skalkin@opensynergy.com>
Subject: [PATCH v2 0/1] virtio_bt: Fix alignment in configuration struct
Date:   Tue, 18 Oct 2022 19:30:49 +0200
Message-Id: <20221018173050.581812-1-Igor.Skalkin@opensynergy.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

According to specification [1], "For the device-specific configuration
space, the driver MUST use 8 bit wide accesses for 8 bit wide fields,
16 bit wide and aligned accesses for 16 bit wide fields and 32 bit wide
and aligned accesses for 32 and 64 bit wide fields.".

Current version of the configuration structure has non-aligned 16bit
fields.

This patch adds a second, aligned  version of the configuration structure
and a new feature bit indicating that this version is being used.

[1] https://docs.oasis-open.org/virtio/virtio/v1.1/virtio-v1.1.pdf

Changes in v2:
  The first version of this patch just changed the configuration
  structure in uapi/linux/virtio_bt.h
  This can not be done, because it will break the userspace, so the
  second version offers a less radical approach - it introduces a new
  feature bit and a new configuration structure that both the device
  and the driver will use if this bit is negotiated.

Igor Skalkin (1):
  virtio_bt: Fix alignment in configuration struct

 drivers/bluetooth/virtio_bt.c  | 16 +++++++++++++---
 include/uapi/linux/virtio_bt.h |  8 ++++++++
 2 files changed, 21 insertions(+), 3 deletions(-)

-- 
2.37.2