On Wed, Mar 17, 2021 at 10:54:17PM -0400, Waiman Long wrote: > On 3/17/21 10:24 PM, Boqun Feng wrote: > > Hi Waiman, > > > > Just a question out of curiosity: how does this problem hide so long? > > ;-) Because IIUC, both locktorture and ww_mutex_lock have been there for > > a while, so why didn't we spot this earlier? > > > > I ask just to make sure we don't introduce the problem because of some > > subtle problems in lock(dep). > > > You have to explicitly specify ww_mutex in the locktorture module parameter > to run the test. ww_mutex is usually not the intended target of testing as > there aren't that many places that use it. Even if someone run it, it > probably is not on a debug kernel. > > Our QA people try to run locktorture on ww_mutex and discover that. >
Got it. Thanks ;-) Regards, Boqun > Cheers, > Longman >