5.15-stable review patch. If anyone has any objections, please let me know.
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From: John Fastabend john.fastabend@gmail.com
[ Upstream commit bce22552f92ea7c577f49839b8e8f7d29afaf880 ]
Now that the backlog manages the reschedule() logic correctly we can drop the partial fix to reschedule from recvmsg hook.
Rescheduling on recvmsg hook was added to address a corner case where we still had data in the backlog state but had nothing to kick it and reschedule the backlog worker to run and finish copying data out of the state. This had a couple limitations, first it required user space to kick it introducing an unnecessary EBUSY and retry. Second it only handled the ingress case and egress redirects would still be hung.
With the correct fix, pushing the reschedule logic down to where the enomem error occurs we can drop this fix.
Fixes: bec217197b412 ("skmsg: Schedule psock work if the cached skb exists on the psock") Signed-off-by: John Fastabend john.fastabend@gmail.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Reviewed-by: Jakub Sitnicki jakub@cloudflare.com Link: https://lore.kernel.org/bpf/20230523025618.113937-4-john.fastabend@gmail.com Stable-dep-of: 405df89dd52c ("bpf, sockmap: Improved check for empty queue") Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/skmsg.c | 2 -- 1 file changed, 2 deletions(-)
diff --git a/net/core/skmsg.c b/net/core/skmsg.c index e9fddceba390e..51ab1e617d922 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -481,8 +481,6 @@ int sk_msg_recvmsg(struct sock *sk, struct sk_psock *psock, struct msghdr *msg, msg_rx = sk_psock_peek_msg(psock); } out: - if (psock->work_state.skb && copied > 0) - schedule_delayed_work(&psock->work, 0); return copied; } EXPORT_SYMBOL_GPL(sk_msg_recvmsg);