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Date:   Sat, 13 Oct 2018 16:50:56 -0700 (PDT)
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Subject: Re: [PATCH] net/sysfs: Remove devices without receive buffers
From:   David Miller <davem@davemloft.net>
In-Reply-To: <20181013220451.6905.65084.stgit@ltcalpine2-lp9.aus.stglabs.ibm.com>
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From: Michael Bringmann <mwb@linux.vnet.ibm.com>
Date: Sat, 13 Oct 2018 17:05:28 -0500

> Testing ran into a case where a network device was created and
> initialized, but then removed from the system before accepting
> traffic through it.  In this case, no receive buffers were added
> to the device prior to attempting to release the driver.  This
> resulted in generation of a WARNING notice/stack trace in the
> console log like,

That's not legal.

The device must setup all of this kind of state before calling
register_netdevice().  And this must happen for reasons other than the
crash situation mentioned here.

Please fix the ibmvnic driver to not register partially setup netdev
objects.

Thank you.