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Date:   Wed, 6 Jan 2021 18:01:58 +0200
From:   Leon Romanovsky <leon@kernel.org>
To:     Jason Gunthorpe <jgg@nvidia.com>
Cc:     Lu Baolu <baolu.lu@linux.intel.com>, tglx@linutronix.de,
        ashok.raj@intel.com, kevin.tian@intel.com, dave.jiang@intel.com,
        megha.dey@intel.com, dwmw2@infradead.org,
        alex.williamson@redhat.com, bhelgaas@google.com,
        dan.j.williams@intel.com, dmaengine@vger.kernel.org,
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        parav@mellanox.com, pbonzini@redhat.com, rafael@kernel.org,
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        shahafs@mellanox.com, tony.luck@intel.com, vkoul@kernel.org,
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Subject: Re: [RFC PATCH v2 1/1] platform-msi: Add platform check for
 subdevice irq domain
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On Wed, Jan 06, 2021 at 11:23:39AM -0400, Jason Gunthorpe wrote:
> On Wed, Jan 06, 2021 at 12:40:17PM +0200, Leon Romanovsky wrote:
>
> > I asked what will you do when QEMU will gain needed functionality?
> > Will you remove QEMU from this list? If yes, how such "new" kernel will
> > work on old QEMU versions?
>
> The needed functionality is some VMM hypercall, so presumably new
> kernels that support calling this hypercall will be able to discover
> if the VMM hypercall exists and if so superceed this entire check.

Let's not speculate, do we have well-known path?
Will such patch be taken to stable@/distros?

Thanks

>
> Jason