On Wed, Oct 02, 2013 at 03:34:41PM -0600, Chris Murphy wrote: > > On Oct 2, 2013, at 2:59 PM, Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > > On Wed, Oct 02, 2013 at 12:33:00PM -0600, Chris Murphy wrote: > >> > >> On Oct 2, 2013, at 12:02 PM, Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > >> > >>> On Wed, Oct 02, 2013 at 07:24:10PM +0200, Henrik Rydberg wrote: > >>>> On Wed, Oct 02, 2013 at 09:47:18AM -0700, Guenter Roeck wrote: > >>>>> On Wed, Oct 02, 2013 at 06:34:18PM +0200, Henrik Rydberg wrote: > >>>>>>>>> One thing I have seen in all logs is the earlier "send_byte fail" message, so > >>>>>>>>> I think that is a pre-requisite. > >>>>>>>> > >>>>>>>> Not necessarily - it could be that the patch actually fixes the root > >>>>>>>> cause. One possible scenario is that on recent SMCs, some of the > >>>>>>>> commands produce more data than we actually read. This would > >>>>>>>> eventually lead to both data corruption and overflow somwhere in the > >>>>>>>> SMC internals. If the original SMC error is interpreted as a read > >>>>>>>> buffer overflow, then that problem should be fixed with this patch. > >>>>>>>> > >>>>>>> > >>>>>>> Good point. > >>>>>>> > >>>>>>> But shouldn't we at least get the "flushed %d bytes" warning message in this case ? > >>>>>> > >>>>>> The explanation I have there is that the (newer) SMC needs the > >>>>>> application to read the 'no more bytes' or it will get confused. It > >>>>>> makes sense, if the number of bytes to read is no longer specified. > >>>>>> > >>>>> You mean that just reading from APPLESMC_CMD_PORT would solve the problem ? > >>>>> That might make sense. > >>>> > >>>> It also points at the possibility of a smaller patch to test, but I > >>>> have not had the time to check this very deeply myself: > >>>> > >>> I like this patch much more than the previous patch. Chris, can you test it ? > >> > >> Yes. Building now. What kernel message should I be looking for? At least on 2011 and 2012 laptops I have yet to see an Oops related to smc. The kernel with previous patch at least is not causing problems on them so far, which works well as I can test more on the 2008 model. > >> > > None, if I understand correctly and if the patch really fixes the root cause > > of the problem. > > A vast majority of the Ooops I've had are when booting from flash media, testing Fedora installs. Is it possible the much slower kernel load and boot time is a trigger? If so, I'll look into modifying the media to accept the custom kernel and requisite fat initramfs. > Yes, that could be a possible trigger. I thought it might be triggered by faster boot (as one gets with 3.10 and 3.11), but slow boot is just as likely. Guenter _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
