This is a note to let you know that I've just added the patch titled
tcp: tcp_mark_head_lost is only valid for sack-tcp
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tcp-tcp_mark_head_lost-is-only-valid-for-sack-tcp.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6ee2a5196d60236c146834d81e414275ed62a7ba
Author: zhang kai <zhangkaiheb@xxxxxxx>
Date: Thu May 7 11:08:30 2020 +0800
tcp: tcp_mark_head_lost is only valid for sack-tcp
[ Upstream commit 636ef28d6e4d174e424102466caf572b0406fb0e ]
so tcp_is_sack/reno checks are removed from tcp_mark_head_lost.
Signed-off-by: zhang kai <zhangkaiheb@xxxxxxx>
Acked-by: Neal Cardwell <ncardwell@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Stable-dep-of: a6458ab7fd4f ("UPSTREAM: tcp: fix DSACK undo in fast recovery to call tcp_try_to_open()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 87a10bb11eb0b..dc446d7c9e0f2 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2202,8 +2202,7 @@ static bool tcp_time_to_recover(struct sock *sk, int flag)
}
/* Detect loss in event "A" above by marking head of queue up as lost.
- * For non-SACK(Reno) senders, the first "packets" number of segments
- * are considered lost. For RFC3517 SACK, a segment is considered lost if it
+ * For RFC3517 SACK, a segment is considered lost if it
* has at least tp->reordering SACKed seqments above it; "packets" refers to
* the maximum SACKed segments to pass before reaching this limit.
*/
@@ -2211,10 +2210,9 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- int cnt, oldcnt, lost;
- unsigned int mss;
+ int cnt;
/* Use SACK to deduce losses of new sequences sent during recovery */
- const u32 loss_high = tcp_is_sack(tp) ? tp->snd_nxt : tp->high_seq;
+ const u32 loss_high = tp->snd_nxt;
WARN_ON(packets > tp->packets_out);
skb = tp->lost_skb_hint;
@@ -2237,26 +2235,11 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head)
if (after(TCP_SKB_CB(skb)->end_seq, loss_high))
break;
- oldcnt = cnt;
- if (tcp_is_reno(tp) ||
- (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED))
+ if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)
cnt += tcp_skb_pcount(skb);
- if (cnt > packets) {
- if (tcp_is_sack(tp) ||
- (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) ||
- (oldcnt >= packets))
- break;
-
- mss = tcp_skb_mss(skb);
- /* If needed, chop off the prefix to mark as lost. */
- lost = (packets - oldcnt) * mss;
- if (lost < skb->len &&
- tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb,
- lost, mss, GFP_ATOMIC) < 0)
- break;
- cnt = packets;
- }
+ if (cnt > packets)
+ break;
tcp_skb_mark_lost(tp, skb);
@@ -2883,8 +2866,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
if (tcp_try_undo_partial(sk, prior_snd_una))
return;
/* Partial ACK arrived. Force fast retransmit. */
- do_lost = tcp_is_reno(tp) ||
- tcp_force_fast_retransmit(sk);
+ do_lost = tcp_force_fast_retransmit(sk);
}
if (tcp_try_undo_dsack(sk)) {
tcp_try_keep_open(sk);
