Quoting Mika Westerberg (2023-08-31 22:50:11) > On Wed, Aug 30, 2023 at 06:14:01PM -0700, Stephen Boyd wrote: > > It's possible for the polling loop in busy_loop() to get scheduled away > > for a long time. > > > > status = ipc_read_status(scu); > > <long time scheduled away> > > if (!(status & IPC_STATUS_BUSY)) > > How can the status bit change here as we are the only user and the SCU > access is serialized by ipclock? I don't know how the SCU works. I thought that IPC_STATUS_BUSY bit was cleared by the SCU when it was done processing. With that assumption, I tried to show that the status is read and then the process schedules away for a long time and has an outdated view of the busy bit.