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From:   Long Li <longli@microsoft.com>
To:     Dexuan Cui <decui@microsoft.com>,
        "longli@linuxonhyperv.com" <longli@linuxonhyperv.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        Rob Herring <robh@kernel.org>,
        Bjorn Helgaas <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>
Subject: RE: [Patch v2 1/2] PCI: hv: Fix a race condition when removing the
 device
Thread-Topic: [Patch v2 1/2] PCI: hv: Fix a race condition when removing the
 device
Thread-Index: AQHXNzrFBLwYwYTj8kqzheBKY3VooKrBsNwAgAC786CAAAVKAIAAAe5A
Date:   Fri, 23 Apr 2021 18:49:21 +0000
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> Subject: RE: [Patch v2 1/2] PCI: hv: Fix a race condition when removing t=
he
> device
>=20
> > From: Long Li <longli@microsoft.com>
> > Sent: Friday, April 23, 2021 11:32 AM
> > > ...
> > > If we test "rmmod pci-hyperv", I suspect the warning will be printed:
> > > hv_pci_remove() -> hv_pci_bus_exit() -> hv_pci_start_relations_work()=
:
> >
> > In most case, it will not print anything.
>=20
> If I read the code correctly, I think the warning is printed _every time_=
 we
> unload pci-hyperv.

Okay I see what you mean. I'll remove this message.

>=20
> > It will print something if there is a PCI_BUS_RELATION work pending at
> > the time of remove. The same goes to PCI_EJECT. In those cases, the
> > message is valuable to troubleshooting.