On Thu, Jun 29, 2017 at 10:29:12AM -0600, Jeffrey Hugo wrote: > On 6/27/2017 6:11 PM, Paul E. McKenney wrote: > >On Tue, Jun 27, 2017 at 04:32:09PM -0600, Jeffrey Hugo wrote: > >>On 6/22/2017 9:34 PM, Paul E. McKenney wrote: > >>>On Wed, Jun 21, 2017 at 09:18:53AM -0700, Paul E. McKenney wrote: > >>>>No worries, and I am very much looking forward to seeing the results of > >>>>your testing. > >>> > >>>And please see below for an updated patch based on LKML review and > >>>more intensive testing. > >>> > >> > >>I spent some time on this today. It didn't go as I expected. I > >>validated the issue is reproducible as before on 4.11 and 4.12 rcs 1 > >>through 4. However, the version of stress-ng that I was using ran > >>into constant errors starting with rc5, making it nearly impossible > >>to make progress toward reproduction. Upgrading stress-ng to tip > >>fixes the issue, however, I've still been unable to repro the issue. > >> > >>Its my unfounded suspicion that something went in between rc4 and > >>rc5 which changed the timing, and didn't actually fix the issue. I > >>will run the test overnight for 5 hours to try to repro. > >> > >>The patch you sent appears to be based on linux-next, and appears to > >>have a number of dependencies which prevent it from cleanly applying > >>on anything current that I'm able to repro on at this time. Do you > >>want to provide a rebased version of the patch which applies to say > >>4.11? I could easily test that and report back. > > > >Here is a very lightly tested backport to v4.11. > > > > Works for me. Always reproduced the lockup within 2 minutes on stock > 4.11. With the change applied, I was able to test for 2 hours in > the same conditions, and 4 hours with the full system and not > encounter an issue. > > Feel free to add: > Tested-by: Jeffrey Hugo <jhugo@xxxxxxxxxxxxxx> Applied, thank you! > I'm going to go back to 4.12-rc5 and see if I can get either repro > the issue, or identify what changed. Hopefully I can get to > linux-next and double check the original version of the change as > well. Looking forward to hearing what you find! Thanx, Paul
