On Tue, Sep 26, 2023 at 10:32:39AM +0800, Jason Wang wrote: > It's the implementation details in legacy. The device needs to make > sure (reset) the driver can work (is done before get_status return). I think that there's no way to make it reliably work for all legacy drivers. They just assumed a software backend and did not bother with DMA ordering. You can try to avoid resets, they are not that common so things will tend to mostly work if you don't stress them to much with things like hot plug/unplug in a loop. Or you can try to use a driver after 2011 which is more aware of hardware ordering and flushes the reset write with a read. One of these two tricks, I think, is the magic behind the device exposing memory bar 0 that you mention. -- MST
