On Thu, 27 Jul 2006 20:12:45 +0100, Thiemo Seufer <ths@xxxxxxxxxxxx> wrote: > IOW, binary analysis can't be expected to provide full accuracy, but > we can live with a reasonable approximation, I think. Yes, this is a starting point. The patch (and current mips get_wchan() implementation) tries to do is what I used to do to analyze stack dump by hand. 1. Determine PC and SP. 2. Disassemble a function containing the PC address. 3. If the function is leaf, make use RA for new PC. 4. Otherwise, obtain saved RA from stack and use it for new PC. 5. Calculate new SP by undoing "addiu sp,sp,-imm". 6. Back to (2). While it is hard to make the get_frame_info() perfect, this approach might fail sometimes. But it can work well for most case, and if it did well we can get very good stack trace than current one (which may contain so many false entries). If you wanted to know the difference, please try ALT-SYSRQ-T (or BREAK-T for serial console) with and without this patch :-) --- Atsushi Nemoto
