From: "Paul E. McKenney" <paul...@linux.vnet.ibm.com> Date: Tue, 25 Jul 2017 20:55:45 -0700
> On Tue, Jul 25, 2017 at 02:10:29PM -0700, David Miller wrote: >> Just to report, turning softlockup back on fixes things for me on >> sparc64 too. > > Very good! > >> The thing about softlockup is it runs an hrtimer, which seems to run >> about every 4 seconds. > > I could see where that could shake things loose, but I am surprised that > it would be needed. I ran a short run with CONFIG_SOFTLOCKUP_DETECTOR=y > with no trouble, but I will be running a longer test later on. > >> So I wonder if this is a NO_HZ problem. > > Might be. My tests run with NO_HZ_FULL=n and NO_HZ_IDLE=y. What are > you running? (Again, my symptoms are slightly different, so I might > be seeing a different bug.) I run with NO_HZ_FULL=n and NO_HZ_IDLE=y, just like you. To clarify, the symptoms show up with SOFTLOCKUP_DETECTOR disabled.
