On Wed, May 22, 2019 at 09:48:10PM -0600, Keith Busch wrote: > Yeah, that's a good question. A FW update may have been initiated out > of band or from another host entirely. The driver can't count on > preparing for hardware pausing command processing before it's > happened, but we'll always find out asynchronously after it's too late > to freeze. I don't think that is the case at least for spec compliant devices. >From NVMe 1.3: Figure 49: Asynchronous Event Information - Notice 1h Firmware Activation Starting: The controller is starting a firmware activation process during which command processing is paused. Host software may use CSTS.PP to determine when command processing has resumed. To clear this event, host software reads the Firmware Slot Information log page. So we are supposed to get an AEN before the device stops processing commands.