On 14-09-22, 17:02, Richard Fitzgerald wrote: > The bus and cadence code has several bugs that cause UNATTACH notifications > to either be sent spuriously or to be missed. > > These can be seen occasionally with a single peripheral on the bus, but are > much more frequent with multiple peripherals, where several peripherals > could change state and report in consecutive PINGs. > > The root of all of these bugs seems to be a code design flaw that assumed > every PING status change would be handled separately. However, PINGs are > handled by a workqueue function and there is no guarantee when that function > will be scheduled to run or how much CPU time it will receive. PINGs will > continue while the work function is handling a snapshot of a previous PING > so the code must take account that (a) status could change during the > work function and (b) there can be a backlog of changes before the IRQ work > function runs again. Applied, thanks -- ~Vinod
