From mboxrd@z Thu Jan  1 00:00:00 1970
From: Halil Pasic <pasic@linux.ibm.com>
Subject: Re: [PATCH v4 4/8] s390/airq: use DMA memory for adapter interrupts
Date: Wed, 12 Jun 2019 15:33:24 +0200
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	<20190612023231.7da4908c.pasic@linux.ibm.com>
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To: Cornelia Huck <cohuck@redhat.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>, linux-s390@vger.kernel.org, Thomas Huth <thuth@redhat.com>, Claudio Imbrenda <imbrenda@linux.ibm.com>, kvm@vger.kernel.org, Sebastian Ott <sebott@linux.ibm.com>, "Michael S. Tsirkin" <mst@redhat.com>, Farhan Ali <alifm@linux.ibm.com>, Heiko Carstens <heiko.carstens@de.ibm.com>, Eric Farman <farman@linux.ibm.com>, virtualization@lists.linux-foundation.org, Christoph Hellwig <hch@infradead.org>, Christian Borntraeger <borntraeger@de.ibm.com>, "Jason J. Herne" <jjherne@linux.ibm.com>, Michael Mueller <mimu@linux.ibm.com>, Viktor Mihajlovski <mihajlov@linux.ibm.com>, Janosch Frank <frankja@linux.ibm.com>
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On Wed, 12 Jun 2019 08:21:27 +0200
Cornelia Huck <cohuck@redhat.com> wrote:

> On Wed, 12 Jun 2019 02:32:31 +0200
> Halil Pasic <pasic@linux.ibm.com> wrote:
> 
> > On Tue, 11 Jun 2019 18:19:44 +0200
> > Cornelia Huck <cohuck@redhat.com> wrote:
> >   
> > > On Tue, 11 Jun 2019 16:27:21 +0200
> > > Halil Pasic <pasic@linux.ibm.com> wrote:  
> 
> > > > IMHO the cleanest thing to do at this stage is to check if the
> > > > airq_iv_cache is NULL and fail the allocation if it is (to preserve
> > > > previous behavior).    
> > > 
> > > That's probably the least invasive fix for now. Did you check whether
> > > any of the other dma pools this series introduces have a similar
> > > problem due to init not failing?
> > >    
> > 
> > Good question!
> > 
> > I did a quick check. virtio_ccw_init() should be OK, because we don't
> > register the driver if allocation fails, so the thing is going to end
> > up dysfunctional as expected.
> > 
> > If however cio_dma_pool_init() fails, then we end up with the same
> > problem with airqs, just on the !AIRQ_IV_CACHELINE code path. It can be
> > fixed analogously: make cio_dma_zalloc() fail all allocation if
> > cio_dma_pool_init() failed before.  
> 
> Ok, makes sense.

v5 is out with the fixes. I have no ack/r-b from you for patch 4. Would
you like to give some, or should I proceed without?

Regards,
Halil