Subject: Re: rcvif, was Cardbus
To: Ken Hornstein <kenh@cmf.nrl.navy.mil>
From: Bill Studenmund <wrstuden@nas.nasa.gov>
List: tech-kern
Date: 12/27/1999 11:09:46
On Mon, 27 Dec 1999, Ken Hornstein wrote:

> >You also have to worry about interface pointers in received mbufs.
> >Given how the pool allocator works, it shouldn't be too hard to write
> >a function which scans all the mbufs.
> 
> Ah, I knew that I was forgetting something :-)  Buuuttt .... wouldn't
> it be easier to look at ipintrq and arpintrq?  Hmmm, no, that might
> not catch mbufs that are being processed.  Rather sticky, that
> one.  There _are_ a lot of spots where rcvif is used, but they all
> seem to check to see if it's NULL .... so maybe a scan through all the
> mbufs to NULL out rcvif might be sufficient.

One thing to be careful about is that some drivers and some protocol
families overload this field with other, generic pointers. if_de does
this, as does the atm stuff. It's not an insurmountable complication, but
you need to think about it. :-)

Take care,

Bill