On Thu, Mar 18, 2021 at 03:29:19PM -0500, Madhavan T. Venkataraman wrote: > > > On 3/18/21 1:26 PM, Mark Brown wrote: > > On Mon, Mar 15, 2021 at 11:57:55AM -0500, madvenka@xxxxxxxxxxxxxxxxxxx wrote: > > > >> + /* Terminal record, nothing to unwind */ > >> + if (fp == (unsigned long) regs->stackframe) { > >> + if (regs->frame_type == TASK_FRAME || > >> + regs->frame_type == EL0_FRAME) > >> + return -ENOENT; > >> return -EINVAL; > >> + } > > > > This is conflating the reliable stacktrace checks (which your series > > will later flag up with frame->reliable) with verifying that we found > > the bottom of the stack by looking for this terminal stack frame record. > > For the purposes of determining if the unwinder got to the bottom of the > > stack we don't care what stack type we're looking at, we just care if it > > managed to walk to this defined final record. > > > > At the minute nothing except reliable stack trace has any intention of > > checking the specific return code but it's clearer to be consistent. > > > > So, you are saying that the type check is redundant. OK. I will remove it > and just return -ENOENT on reaching the final record. Yes please; and please fold that into the same patch that adds the final records. Thanks, Mark.