Subject: Re: [PATCH v2 2/2] ibmvnic: fix race with multiple open/close

From: Sukadev Bhattiprolu <[email-masked]>
Date: Wed, 3 Feb 2021 12:56:52 -0800

Willem de Bruijn [[email-masked]] wrote:
> On Wed, Feb 3, 2021 at 12:10 AM Sukadev Bhattiprolu
> <[email-masked]> wrote:
> >
> > If two or more instances of 'ip link set' commands race and first one
> > already brings the interface up (or down), the subsequent instances
> > can simply return without redoing the up/down operation.
> >
> > Fixes: ed651a10875f ("ibmvnic: Updated reset handling")
> > Reported-by: Abdul Haleem <[email-masked]>
> > Tested-by: Abdul Haleem <[email-masked]>
> > Signed-off-by: Sukadev Bhattiprolu <[email-masked]>
> >
> > ---
> > Changelog[v2] For consistency with ibmvnic_open() use "goto out" and return
> >               from end of function.
> 
> Did you find the code path that triggers this?

Not yet. I need to find time on the system to repro/debug that
> 
> In v1 we discussed how the usual ip link path should not call the
> driver twice based on IFF_UP.

Yes, we can hold this patch for now if necessary. Hopefully Patch 1/2 is
ok.

Sukadev