Date: Fri, 31 Mar 2017 10:20:49 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>, Christoph Hellwig <hch@lst.de>,
        Thorsten Leemhuis <linux@leemhuis.info>,
        virtio-dev@lists.oasis-open.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        rjones@redhat.com
Subject: Re: Random guest crashes since 5c34d002dcc7 ("virtio_pci: use
        shared interrupts for virtqueues")
Message-ID: <20170331082049.GA4485@lst.de>
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On Fri, Mar 31, 2017 at 06:22:31AM +0300, Michael S. Tsirkin wrote:
> I'm not sure why does it fail after 32 on 64 bit, but as
> virtio devices aren't limited to 32 vqs it looks like we
> should go back to requesting the irq only once for all vqs.

Meh.

> 
> Christoph, should I just revert for now, or do you
> want to look into a smaller patch for this?

I think we'll need to do a different patch than just a simple revert,
mostly because so much infrastructure depends on the patch.

I'll take a look over the weekend.

> Another question is looking into intx support - that
> should work but it seems to be broken at the moment.

Does it?  I'm pretty sure I tested it back when I came up with the
series by artifically disabling MSI-X in the kernel.  I can try this
again, though.