On Thu, Oct 16, 2025 at 1:45 PM Michael S. Tsirkin <[email protected]> wrote: > > On Thu, Oct 16, 2025 at 01:39:58PM +0800, Jason Wang wrote: > > > > > > > > Not exactly bufferize, record. E.g. we do not need to send > > > > 100 messages to enable/disable promisc mode - together they > > > > have no effect. > > > > Note that there's a case that multiple commands need to be sent, e.g > > set rx mode. And assuming not all the commands are the best effort, > > kernel VDUSE still needs to wait for the usersapce at least for a > > while. > > Not wait, record. Generate 1st command, after userspace consumed it - > generate and send second command and so on.
Right, that's what I asked in another thread, we still need a timeout here. Then I think it would not be too much difference whether it is VDUSE or CVQ that will fail or break the device. Conceptually, VDUSE can only advertise NEEDS_RESET since it's a device implementation. VDUSE can not simply break the device as it requires synchronization which is not easy. > But for each bit of data, at most one command has to be sent, > we do not care if guest tweaked rx mode 3 times, we only care about > the latest state. Yes, but I want to know what's best when VDUSE meets userspace timeout. Thanks > > -- > MST >

