Re: [PATCH-next v2] kvm: don't try to take mmu_lock while holding the main raw kvm_lock

[Paul Gortmaker <paul.gortmaker@windriver.com>]

[Re: [PATCH-next v2] kvm: don't try to take mmu_lock while holding the main raw kvm_lock] On 26/06/2013 (Wed 23:59) Paolo Bonzini wrote:

> Il 26/06/2013 20:11, Paul Gortmaker ha scritto:
> >  		spin_unlock(&kvm->mmu_lock);
> > +		kvm_put_kvm(kvm);
> >  		srcu_read_unlock(&kvm->srcu, idx);
> >  
> 
> kvm_put_kvm needs to go last.  I can fix when applying, but I'll wait
> for Gleb to take a look too.

I'm curious why you would say that -- since the way I sent it has the
lock tear down be symmetrical and opposite to the build up - e.g.

 		idx = srcu_read_lock(&kvm->srcu);

[...]

+		kvm_get_kvm(kvm);

[...]
 		spin_lock(&kvm->mmu_lock);
 
[...]

 unlock:
 		spin_unlock(&kvm->mmu_lock);
+		kvm_put_kvm(kvm);
 		srcu_read_unlock(&kvm->srcu, idx);
 
You'd originally said to put the kvm_get_kvm where it currently is;
perhaps instead we want the get/put to encompass the whole 
srcu_read locked section?

P.
--

> 
> Paolo