On Sat, Feb 7, 2015 at 11:14 PM, Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> wrote: > On Sat, Feb 07, 2015 at 04:52:05PM -0500, Steven Rostedt wrote: >> On Sat, 7 Feb 2015 12:09:48 -0800 >> "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote: >> >> > The tag sequence has the meaning of: >> > git cherry-pick a1f84a3 >> > git cherry-pick 1b9508f >> > git cherry-pick fd21073 >> > git cherry-pick <this commit> >> > >> > Does that do what you need? >> >> Note, for this case it really doesn't apply, because one patch does not >> depend on the other. >> >> The real bug is that a tracepoint can be called when RCU is not >> watching (cpu is offline). That bug was introduced in 3.17 and is fixed >> by patch 2 with the conditional trace event. >> >> When that bug was fixed, it showed that another bug exists. That is >> that lockdep should not complain if the conditional prevents the bad >> RCU from happening, and this bug was introduced in 3.18. This was fixed >> by the first patch. >> >> They really are two entirely separate bugs, it just happens that the >> test case Sedat had happened to trigger both of them. This is why I >> really don't see why the two need to reference each other. >> >> I'm also going to modify patch 1 to not mention porting the other >> commit (that patch 1 fixes) to 3.17 (from 3.18), as that other commit is >> just a debugging tool and not something that satisfies being >> backported, and the patch that fixes it shouldn't be backported to 3.17 >> either, only to 3.18. > > Thank you for the explanation! I guess I needed to have kept a scorecard > on this one. ;-) > My misunderstanding and thanks again for the clarification. As Steve pointed out, /me needs both patches to fix my broken testcase. My wish was not to forget affected (previous) linux-stable releases when dealing with the issue. - Sedat - -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
