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Tsirkin" To: Parav Pandit Cc: Heng Qi , Halil Pasic , Cornelia Huck , "virtio-comment@lists.linux.dev" , Jason Wang , Xuan Zhuo Subject: Re: [PATCH v5] virtio-net: clarify coalescing parameters settings Message-ID: <20240613021132-mutt-send-email-mst@kernel.org> References: <20240528044702.50603-1-hengqi@linux.alibaba.com> <20240607220246.3213607c.pasic@linux.ibm.com> <1717814062.4461155-1-hengqi@linux.alibaba.com> <20240610144602.57a04723.pasic@linux.ibm.com> <1718026545.7557275-2-hengqi@linux.alibaba.com> <20240610221900.1810ea96.pasic@linux.ibm.com> <1718102433.0456574-3-hengqi@linux.alibaba.com> <20240611122756-mutt-send-email-mst@kernel.org> Precedence: bulk X-Mailing-List: virtio-comment@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jun 11, 2024 at 05:43:18PM +0000, Parav Pandit wrote: > > > > From: Michael S. Tsirkin > > Sent: Tuesday, June 11, 2024 10:00 PM > > > > How we can we make progress with > > the realease but sure we don't make backwards compat a pain? > > > > Ideas? > > > There is no functional break with this relaxation. > Device set some non-zero defaults and driver didn't modify them.... > Anything broken? Unlikely. > And device/driver has better performance, is that a problem? Unlikely. > Yes, it is possible. Driver can cache values it sets and never query device with get. Before anything is set, driver will report incorrect values. What will break as a result? Hard to predict. Given the patch is big, I am inclined to say it just should use a feature bit. -- MST