Calling m_pullup in ether_input

[Gleb Smirnoff]

On Fri, Oct 08, 2004 at 06:15:15PM +0300, Giorgos Keramidas wrote:
G> In ether_input() we unconditionaly discard the mbufs whose m_len is less than
G> ETHER_HDR_LEN.  A bit higher M_PKTHDR has been checked but the check made
G> before discarding the frame doesn't pay attention to the m->m_pkthdr.len (the
G> total packet length).

In my humble opinion, all Ethernet device drivers are intentionally written
in such a way that they always pass an mbuf with contigous Ethernet header
to ether_input().

Why did you write this patch? Do you really have packet loss?

G> I am trying to find out how often this happens, by using the attached patch to
G> count the number of small frames received in ether_input() and the number of
G> failed m_pullup() attempts that result from that.

And what results do you have?

G> Does this change seem reasonable as an instrumentation  of the particular
G> problem or am I unknowingly breaking something in the way ether_input() is
G> supposed to work?

AFAIK, this patch does not break anything but just adds more processing.

-- 
Totus tuus, Glebius.
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