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Tsirkin" To: Parav Pandit Cc: Zhu Lingshan , "cohuck@redhat.com" , "jasowang@redhat.com" , "virtio-comment@lists.linux.dev" , Eugenio =?iso-8859-1?Q?P=E9rez?= , David Stevens Subject: Re: [PATCH V7 v7] virtio: introduce SUSPEND bit in device status Message-ID: <20240903063625-mutt-send-email-mst@kernel.org> References: <88a087ff-676f-4616-a573-a765ca77bef7@amd.com> <47b314dc-d8a2-489e-a84d-6670c176675c@amd.com> <928aa775-c934-4d3e-bd38-48fb6c374fc7@amd.com> <20240903054018-mutt-send-email-mst@kernel.org> <20240903063424-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: <20240903063424-mutt-send-email-mst@kernel.org> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Sep 03, 2024 at 06:35:59AM -0400, Michael S. Tsirkin wrote: > > > > > > But I don't like it that looking at the registers, one does not know the device > > > state. Hidden state is bad for debuggability. > > > We have 4 states: > > > suspending->suspended->resuming->resumed > > > so we need a register with at least 2 bits. > > > > > > we could steal 2 bits from status but it seems a bit much. > > > > > This is why letting the status tell the status and control register to control thing is elegant. > > > No argument here. Or, to be more precise, our status is driver status. If we need to reflect and control device status, we need something else.