On Fri, 20 Dec 2013 07:53:11 -0800, Guenter Roeck wrote: > On Sat, Dec 07, 2013 at 10:05:57AM -0800, Guenter Roeck wrote: > > Some Intel CPUs do not set the 'valid' bit in IA32_THERM_STATUS if the > > temperature is too low to be measured. This condition will not change until > > the CPU is hot enough for its temperature to be measured. Returning an error > > in such conditions is not very useful. Drop checking the valid bit and just > > return the reported temperature instead. > > > > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> > > --- > > I don't think we ever closed on this. Giving it a shot. > > > No feedback. This will go into 3.14 unless there are objections. I have no objection, I just don't want this change to go to stable, I believe it needs a lot of testing on a broad range of hardware before we can even think of it. Reviewed-by: Jean Delvare <khali@xxxxxxxxxxxx> On a related note, I think we already noticed that different CPU models behave differently in low temperature ranges. As an additional data point, I noticed when staring at sensord graphs that my wife's Core2 Duo E8400 does clamp at 40°C (which is 60°C below Tjmax). It never ever reports values below this. Somehow it is a saner implementation than clearing the valid bit. Too bad we have no way to represent this in sysfs. Would it make sense to define for example tempX_floor (can't remember if a better name was ever proposed) so that sensors can report "< 40°C" instead of "40°C" in this case? The problem is that I don't think these clamp values can be read from a register, I'm not even sure if they are documented, so I'm not sure how useful this would be in practice... -- Jean Delvare _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
