2015-08-06 16:35 GMT+09:00 Krzysztof Kozlowski <[email protected]>: > On 06.08.2015 16:29, Srinivas Kandagatla wrote: >> Thanks Krzysztof >> >> On 06/08/15 02:39, Krzysztof Kozlowski wrote: >>>> --- a/drivers/regulator/core.c >>>> >+++ b/drivers/regulator/core.c >>>> >@@ -2919,7 +2919,7 @@ static int _regulator_get_voltage(struct >>>> regulator_dev *rdev) >>>> > } else if (rdev->desc->fixed_uV && (rdev->desc->n_voltages >>>> == 1)) { >>>> > ret = rdev->desc->fixed_uV; >>>> > } else if (rdev->supply) { >>>> >- ret = regulator_get_voltage(rdev->supply); >>>> >+ ret = _regulator_get_voltage(rdev->supply->rdev); >>> Is the 'rdev' and 'rdev->supply' same regulators? If not then you are >>> just hiding false warning by removing locks thus introducing real >>> issue... >> They are the not the same regulators, and hence they are not locking the >> same mutex, looks like this is a false positive warning from lockdep. I >> can't think of any use case which could result in ABBA type lockup too, >> so we can ignore this patch for now. >> >> Not sure why did the lockdep think that this is same lock :-) > > I think the warning appears because the class of lock is the same but > there is nesting information:
Crap... s/there is nesting/there is no nesting/ Maybe it is worth to add it... or remove the lockdep warning if it hits often. > "May be due to missing lock nesting notation" > Fixing this would require adding the nesting information. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
