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From: John Baldwin <jhb@freebsd.org>
To: Davide Italiano <davide@freebsd.org>
Subject: Re: svn commit: r280785 - in head/sys: kern netgraph/atm/sscop
 netgraph/atm/uni sys
Date: Mon, 30 Mar 2015 12:10:07 -0400
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Cc: "svn-src-head@freebsd.org" <svn-src-head@freebsd.org>,
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On Saturday, March 28, 2015 01:48:49 PM Davide Italiano wrote:
> On Sat, Mar 28, 2015 at 12:04 PM, Randall Stewart <rrs@netflix.com> w=
rote:
> > Hmm does the KPI include the size of the callout structure (which i=
s
> > private)?
> >
>=20
> It's KBI, not KPI.
>=20
> > If so I suppose we could change the c_flags/c_iflags to
> > ushort =E2=80=A6
> >
>=20
> I'm not familiar with your changes enough to suggest/propose a fix.
> As I previously mentioned, this looks suspicious KBI-wise to me, and =
I
> reported to you.

The KBI issue makes it much harder to MFC.  In particular, even though
you could move 'c_iflags' to the end to fix most things (though not
callout_pending()), many drivers have 'struct callout foo' inside their=

softc, etc. and this would break existing modules.

OTOH, the uglier hack of adding locking in callout_deactivate() would
preserve the KBI and be safe to merge.

--=20
John Baldwin