From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [4.2] commit d59cfc09c32 (sched, cgroup: replace
 signal_struct->group_rwsem with a global percpu_rwsem) causes regression for
 libvirt/kvm
Date: Wed, 16 Sep 2015 16:19:03 +0200
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Cc: Christian Borntraeger <borntraeger@de.ibm.com>,
	paulmck@linux.vnet.ibm.com, Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	"linux-kernel@vger.kernel.org >> Linux Kernel Mailing List"
	<linux-kernel@vger.kernel.org>, KVM list <kvm@vger.kernel.org>
To: Tejun Heo <tj@kernel.org>, Oleg Nesterov <oleg@redhat.com>
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On 16/09/2015 16:16, Tejun Heo wrote:
> On Wed, Sep 16, 2015 at 02:22:49PM +0200, Oleg Nesterov wrote:
>>> > > If the revert isn't easy, I think backporting rcu_sync is the best bet.
>> > 
>> > I leave this to Paul and Tejun... at least I think this is not v4.2 material.
> Will route reverts through cgroup branch.  Should be pretty painless.
> Nice job on percpu_rwsem.  It's so much better than having to come up
> with a separate middleground solution.

Thanks all for the quick resolution!

Paolo