On (05/07/12 10:52), Avi Kivity wrote: > On 05/07/2012 06:47 AM, Paul E. McKenney wrote: > > On Sun, May 06, 2012 at 11:34:39PM +0300, Sergey Senozhatsky wrote: > > > On (05/06/12 09:42), Paul E. McKenney wrote: > > > > On Sun, May 06, 2012 at 11:55:30AM +0300, Avi Kivity wrote: > > > > > On 05/03/2012 11:02 PM, Sergey Senozhatsky wrote: > > > > > > Hello, > > > > > > 3.4-rc5 > > > > > > > > > > Whoa. > > > > > > > > > > Looks like inconsistent locking between cpufreq and > > > > > synchronize_srcu_expedited(). kvm triggered this because it is one of > > > > > the few users of synchronize_srcu_expedited(), but I don't think it is > > > > > doing anything wrong directly. > > > > > > > > > > Dave, Paul? > > > > > > > > SRCU hasn't changed much in mainline for quite some time. Holding > > > > the hotplug mutex across a synchronize_srcu() is a bad idea, though. > > > > > > > > However, there is a reworked implementation (courtesy of Lai Jiangshan) > > > > in -rcu that does not acquire the hotplug mutex. Could you try that out? > > > > > > > > > > Paul, should I try solely -rcu or there are several commits to pick up and apply > > > on top of -linus tree? > > > > If you want the smallest possible change, take the rcu/srcu branch of -rcu. > > If you want the works, take the rcu/next branch of -rcu. > > > > You can find -rcu at: > > > > git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git > > To make the difference even smaller, merge the above branch with v3.4-rc5. > I'm unable to reproduce the issue on 3.4-rc6 so far. So I guess this will take some time. Sergey -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
