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Date:   Thu, 13 Apr 2023 15:34:06 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     "Michael Kelley (LINUX)" <mikelley@microsoft.com>
Cc:     Wei Liu <wei.liu@kernel.org>,
        Jinank Jain <jinankjain@linux.microsoft.com>,
        "g@liuwe-devbox-debian-v2" <g@liuwe-devbox-debian-v2>,
        Jinank Jain <jinankjain@microsoft.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Dexuan Cui <decui@microsoft.com>,
        "lpieralisi@kernel.org" <lpieralisi@kernel.org>,
        "kw@linux.com" <kw@linux.com>, "robh@kernel.org" <robh@kernel.org>,
        "bhelgaas@google.com" <bhelgaas@google.com>,
        "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
        "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "nunodasneves@linux.microsoft.com" <nunodasneves@linux.microsoft.com>
Subject: Re: [PATCH] PCI: hv: Use nested hypercall for retargeting interrupts
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On Thu, Apr 13, 2023 at 03:05:09AM +0000, Michael Kelley (LINUX) wrote:
> From: Wei Liu <wei.liu@kernel.org> Sent: Wednesday, April 12, 2023 6:23 PM
> > 
> > On Tue, Apr 04, 2023 at 11:35:46AM +0000, Jinank Jain wrote:
> > > In case of nested MSHV, retargeting interrupt hypercall should be sent
> > > to L0 hypervisor instead of L1 hypervisor.
> > >
> > > Signed-off-by: Jinank Jain <jinankjain@linux.microsoft.com>
> > 
> > Applied to hyperv-next. Thanks.
> 
> I'd like to hold off on taking this change.  Nuno and I are discussing
> how best to handle nested hypercalls.  In addition to the proposed
> nested changes,  we have hypercall changes coming as part of the
> TDX and fully enlightened SNP patch sets.  If possible, I'd like to
> avoid adding logic at the hv_do_hypercall() call sites.  It's not clear
> whether avoiding such logic will really be feasible, but I'd like to
> think about it for a bit before reaching that conclusion.

I thought that discussion will go on for a while but this patch fixed a
real bug.

Holding off is fine too. I will remove this patch from hyperv-next.

Thanks,
Wei.

> 
> Michael
>