[PATCH 20/30] netvm: filter emergency skbs.

Peter Zijlstra
2008-03-20T20:37:04Z

[-- Attachment #1: netvm-sk_filter.patch --]
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Toss all emergency packets not for a SOCK_MEMALLOC socket. This ensures our
precious memory reserve doesn't get stuck waiting for user-space.

The correctness of this approach relies on the fact that networks must be
assumed lossy.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
include/net/sock.h | 3 +++
1 file changed, 3 insertions(+)

Index: linux-2.6/include/net/sock.h
===================================================================
--- linux-2.6.orig/include/net/sock.h
+++ linux-2.6/include/net/sock.h
@@ -1007,6 +1007,9 @@ static inline int sk_filter(struct sock
{
int err;
struct sk_filter *filter;
+
+ if (skb_emergency(skb) && !sk_has_memalloc(sk))
+ return -ENOMEM;

err = security_sock_rcv_skb(sk, skb);
if (err)

--