From 0943404b1f3b178e1e54386dadcbf4f2729c7762 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 16 Feb 2026 19:36:53 +0000 Subject: [PATCH] net: do not delay zero-copy skbs in skb_attempt_defer_free() After the blamed commit, TCP tx zero copy notifications could be arbitrarily delayed and cause regressions in applications waiting for them. Signed-off-by: Eric Dumazet Fixes: e20dfbad8aab ("net: fix napi_consume_skb() with alien skbs") Reviewed-by: Jason Xing Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20260216193653.627617-1-edumazet@google.com Signed-off-by: Jakub Kicinski --- net/core/skbuff.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 699c401a5eae..dc47d3efc72e 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -7266,10 +7266,15 @@ void skb_attempt_defer_free(struct sk_buff *skb) { struct skb_defer_node *sdn; unsigned long defer_count; - int cpu = skb->alloc_cpu; unsigned int defer_max; bool kick; + int cpu; + /* zero copy notifications should not be delayed. */ + if (skb_zcopy(skb)) + goto nodefer; + + cpu = skb->alloc_cpu; if (cpu == raw_smp_processor_id() || WARN_ON_ONCE(cpu >= nr_cpu_ids) || !cpu_online(cpu)) { -- 2.30.2