On Oct 2, 2013, at 2:59 PM, Guenter Roeck <li...@roeck-us.net> wrote:
> On Wed, Oct 02, 2013 at 12:33:00PM -0600, Chris Murphy wrote: >> >> On Oct 2, 2013, at 12:02 PM, Guenter Roeck <li...@roeck-us.net> 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. Chris-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
