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From:   Thomas Gleixner <tglx@linutronix.de>
To:     "Michael S. Tsirkin" <mst@redhat.com>
Cc:     Jason Wang <jasowang@redhat.com>,
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        X86 ML <x86@kernel.org>
Subject: Re: [PATCH 6/9] virtio_pci: harden MSI-X interrupts
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Date:   Tue, 14 Sep 2021 10:29:35 +0200
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On Mon, Sep 13 2021 at 16:54, Michael S. Tsirkin wrote:
> On Mon, Sep 13, 2021 at 09:38:30PM +0200, Thomas Gleixner wrote:
>> and disable it again
>> before reset() is invoked. That's a question of general robustness and
>> not really a question of trusted hypervisors and encrypted guests.
>
> We can do this for some MSIX interrupts, sure. Not for shared interrupts though.

But you have to make sure that the handler does not run before and after
the defined points. And that's even more important for shared because
with shared interrupts the interrupt can be raised at any point in time
via the other devices which share the line.

Thanks,

        tglx