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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 2/2] PCI: hv: Remove unused refcount and supporting
 functions for handling bus device removal
Thread-Topic: [Patch v2 2/2] PCI: hv: Remove unused refcount and supporting
 functions for handling bus device removal
Thread-Index: AQHXNzrM+OyMyEMRRUyvNwFTh5HICqrBszkAgAC9Z0A=
Date:   Fri, 23 Apr 2021 18:40:12 +0000
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> Subject: RE: [Patch v2 2/2] PCI: hv: Remove unused refcount and supportin=
g
> functions for handling bus device removal
>=20
> > From: longli@linuxonhyperv.com <longli@linuxonhyperv.com>
> > Sent: Wednesday, April 21, 2021 10:46 PM
> >
> > With the new method of flushing/stopping the workqueue before doing
> > bus removal, the old mechanisum of using refcount and wait for
> > completion
>=20
> mechanisum -> mechanism
>=20
> > is no longer needed. Remove those dead code.
> >
> > Signed-off-by: Long Li <longli@microsoft.com>
> > ---
>=20
> The patch looks good to me. BTW, can we also remove get_pcichild() and
> put_pcichild() in an extra patch? I suspect we don't really need those ei=
ther.

Those two functions are for protecting accessing to the devices on the hbus=
. There are interactions from PCI layer that need guarantee from hbus that =
the device is present at the time of access.

Why do you think we don't' need those?