On Wed, Jun 23, 2021 at 12:58:58PM +0200, Matteo Croce wrote: > From: Matteo Croce <mcroce@xxxxxxxxxxxxx> > > On a very loaded system, if there are many events queued up from multiple > attach/detach cycles, it's impossible to match them up with the > LOOP_CONFIGURE or LOOP_SET_FD call, since we don't know where the position > of our own association in the queue is[1]. > Not even an empty uevent queue is a reliable indication that we already > received the uevent we were waiting for, since with multi-partition block > devices each partition's event is queued asynchronously and might be > delivered later. > > Increment the disk sequence number when setting or changing the backing > file, so the userspace knows which backing file generated the event: Instead of manually incrementing the sequence here, can we make loop generate the DISK_EVENT_MEDIA_CHANGE event on a backing device (aka media) change?