On Wed, Jun 26, 2019 at 08:56:00AM +1000, Benjamin Herrenschmidt wrote: > On Tue, 2019-06-25 at 23:06 +0800, Muchun Song wrote: > > Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> 于2019年6月19日周三 > > 上午5:51写道： > > > > > > On Tue, 2019-06-18 at 18:13 +0200, Greg KH wrote: > > > > > > > > Again, I am totally confused and do not see a patch in an email > > > > that > > > > I > > > > can apply... > > > > > > > > Someone needs to get people to agree here... > > > > > > I think he was hoping you would chose which solution you prefered > > > here > > > > Yeah, right, I am hoping you would chose which solution you prefered > > here. > > Thanks. > > > > > :-) His original or the one I suggested instead. I don't think > > > there's > > > anybody else with understanding of sysfs guts around to form an > > > opinion. > > > > > Muchun, I don't think Greg still has the previous emails. He deals with > too much to keep track of old stuff. > > Can you send both patches tagged as [OPT1] and [OPT2] along with a > comment in one go so Greg can see both and decide ? That would be wonderful, thank you as I can't really find the "latest" versions of both options. > I think looking at the refcount is fragile, I might be wrong, but I > think it mostly paper over the root of the problem which is the fact > that the lock isn't taken accross both operations, thus exposing the > race. But I'm happy if Greg prefers your approach as long as it's > fixed. I'll look at them and try to figure this out next week, thanks. greg k-h
