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From:   Michael Kelley <mikelley@microsoft.com>
To:     Nathan Chancellor <natechancellor@gmail.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>
CC:     "linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "clang-built-linux@googlegroups.com" 
        <clang-built-linux@googlegroups.com>,
        Sami Tolvanen <samitolvanen@google.com>
Subject: RE: [PATCH v2] hv_netvsc: Fix netvsc_start_xmit's return type
Thread-Topic: [PATCH v2] hv_netvsc: Fix netvsc_start_xmit's return type
Thread-Index: AQHWHYZG1Nlm2xaz8EKxX/yhRvOanaiQyLNQ
Date:   Thu, 30 Apr 2020 00:06:09 +0000
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References: <20200428100828.aslw3pn5nhwtlsnt@liuwe-devbox-debian-v2.j3c5onc20sse1dnehy4noqpfcg.zx.internal.cloudapp.net>
 <20200428175455.2109973-1-natechancellor@gmail.com>
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From: Nathan Chancellor <natechancellor@gmail.com> Sent: Tuesday, April 28,=
 2020 10:55 AM
>=20
> Do note that netvsc_xmit still returns int because netvsc_xmit has a
> potential return from netvsc_vf_xmit, which does not return netdev_tx_t
> because of the call to dev_queue_xmit.
>=20
> I am not sure if that is an oversight that was introduced by
> commit 0c195567a8f6e ("netvsc: transparent VF management") or if
> everything works properly as it is now.
>=20
> My patch is purely concerned with making the definition match the
> prototype so it should be NFC aside from avoiding the CFI panic.
>=20

While it probably works correctly now, I'm not too keen on just
changing the return type for netvsc_start_xmit() and assuming the
'int' that is returned from netvsc_xmit() will be correctly mapped to
the netdev_tx_t enum type.  While that mapping probably happens
correctly at the moment, this really should have a more holistic fix.

Nathan -- are you willing to look at doing the more holistic fix?  Or
should we see about asking Haiyang Zhang to do it?

Michael