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Date:   Thu, 15 Jul 2021 11:57:21 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Halil Pasic <pasic@linux.ibm.com>
Cc:     Tony Krowiak <akrowiak@linux.ibm.com>, linux-s390@vger.kernel.org,
        linux-kernel@vger.kernel.org, borntraeger@de.ibm.com,
        cohuck@redhat.com, pasic@linux.vnet.ibm.com, jjherne@linux.ibm.com,
        alex.williamson@redhat.com, kwankhede@nvidia.com,
        frankja@linux.ibm.com, david@redhat.com, imbrenda@linux.ibm.com,
        hca@linux.ibm.com
Subject: Re: [PATCH] s390/vfio-ap: do not open code locks for
 VFIO_GROUP_NOTIFY_SET_KVM notification
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On Thu, Jul 15, 2021 at 01:31:36PM +0200, Halil Pasic wrote:

> I'm in favor of rewriting this to use rw_semaphore. I'm not in favor
> of proclaiming this a fix for stable, because for that you first have
> to prove that you fix a real problem.

So Tony keeps saying that a rwsem couldn't work for what kvm_busy
does, so it should be trivial enough to put in the rwsem and capture
the lockdep spew.
 
> I hope we are on the same page.

Sure

Jason