> -----Original Message----- > From: Hollis Blanchard [mailto:hollisb@xxxxxxxxxx] > Sent: Wednesday, May 13, 2009 12:39 AM > To: Liu Yu-B13201 > Cc: kvm-ppc@xxxxxxxxxxxxxxx > Subject: RE: single-step issue > > > > I don't think this problem should be an issue for > single-stepping, but > > > it suggests we can't reliably use hardware's > IAC/DAC/DVC/etc. We could > > > replace IAC with software breakpoints, and maybe DAC with > page faults > > > (with high overhead), but there's no software emulation for > > > DVC or e.g. > > > "branch taken" events that I can see. > > > > > > > Seems gdbserver uses software breakpoint by default. > > Not sure how to enable hardware breakpoint in gdbserver. > > I think historically it has not been possible, but I've heard there is > ongoing work to add hardware breakpoint support to gdb for 440, at > least. > > My point though is that the hardware debug mechanisms really > need "guest > mode" awareness to be useful to us, and I'm afraid they don't. > > As a side note, you might want to inquire internally about how e500mc > will handle this situation... > Yes. For e500mc there is a configuration that make debug interrupt only *occur* in guest. -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
