Re: [RFC][PATCH] Fixing SA/SP dumps on netlink/af_key

David Miller wrote:

From: Timo_Teräs <redacted>
Date: Thu, 17 Jan 2008 13:00:09 +0200

quoted

IMHO, it's a lot better then losing >50% of entries and the end
of sequence message on big dumps. SPD and SADB are not that
volatile; in most of the cases the dump would be as good as an
atomic one.

I humbly disagree with you.  Interface behavior stability
is more important.

Small SPDs/SADBs would still be dumped atomically. The patch
affects only the cases when the receive queue is getting full.

quoted

I'm not sure if there's other major applications that we should
be concerned about, but at least ipsec-tools racoon does not
expect to get atomic dumps (which btw, comes originally from BSD).

Racoon was written as an addon to the BSD stack by an IPV6/IPSEC
project in Japan named KAME, it did not "come from BSD".  It was
added to BSD.

There are also other BSD based IPSEC daemons such as the one written
by the OpenBSD folks.

Yes. I meant that it was originally written to be used in BSD. The
Linux port came later. Sorry for the ambiguous wording.

I don't think this is arguable at all.  We're not changing semantics
over what we've done for 4+ years and applications might depend upon.
It's for a deprecated interface, which makes any semantic changes that
much less inviting.

You can argue all you want, but it will not change the invariants in
the previous paragraph.

True. If no one else agrees with me, I'll drop it. I can always run
my own patched kernel.

I'd appreciate feedback on the xfrm changes. I'll try to make that
part usable patch against net-2.6.25 git tree next week.