5.4-stable patches

added patches:
	revert-xsk-do-not-sleep-in-poll-when-need_wakeup-set.patch

diff --git a/queue-5.4/revert-xsk-do-not-sleep-in-poll-when-need_wakeup-set.patch b/queue-5.4/revert-xsk-do-not-sleep-in-poll-when-need_wakeup-set.patch
new file mode 100644 (file)
index 0000000..2f2ba44
--- /dev/null
+++ b/queue-5.4/revert-xsk-do-not-sleep-in-poll-when-need_wakeup-set.patch
@@ -0,0 +1,46 @@
+From 0706a78f31c4217ca144f630063ec9561a21548d Mon Sep 17 00:00:00 2001
+From: Magnus Karlsson <magnus.karlsson@intel.com>
+Date: Fri, 17 Dec 2021 15:56:46 +0100
+Subject: Revert "xsk: Do not sleep in poll() when need_wakeup set"
+
+From: Magnus Karlsson <magnus.karlsson@intel.com>
+
+commit 0706a78f31c4217ca144f630063ec9561a21548d upstream.
+
+This reverts commit bd0687c18e635b63233dc87f38058cd728802ab4.
+
+This patch causes a Tx only workload to go to sleep even when it does
+not have to, leading to misserable performance in skb mode. It fixed
+one rare problem but created a much worse one, so this need to be
+reverted while I try to craft a proper solution to the original
+problem.
+
+Fixes: bd0687c18e63 ("xsk: Do not sleep in poll() when need_wakeup set")
+Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
+Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
+Link: https://lore.kernel.org/bpf/20211217145646.26449-1-magnus.karlsson@gmail.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ net/xdp/xsk.c |    4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/net/xdp/xsk.c
++++ b/net/xdp/xsk.c
+@@ -434,6 +434,8 @@ static __poll_t xsk_poll(struct file *fi
+       struct xdp_sock *xs = xdp_sk(sk);
+       struct xdp_umem *umem;
+ 
++      sock_poll_wait(file, sock, wait);
++
+       if (unlikely(!xsk_is_bound(xs)))
+               return mask;
+ 
+@@ -445,8 +447,6 @@ static __poll_t xsk_poll(struct file *fi
+               else
+                       /* Poll needs to drive Tx also in copy mode */
+                       __xsk_sendmsg(sk);
+-      } else {
+-              sock_poll_wait(file, sock, wait);
+       }
+ 
+       if (xs->rx && !xskq_empty_desc(xs->rx))

diff --git a/queue-5.4/series b/queue-5.4/series
index 7bea02a090430cbd9e6bafd2c07da539935ad480..bc9ad2a37656d2ce300d8ac38d0c7530ac0f0e71 100644 (file)
--- a/queue-5.4/series
+++ b/queue-5.4/series
@@ -63,3 +63,4 @@ scsi-scsi_debug-sanity-check-block-descriptor-length-in-resp_mode_select.patch
 rcu-mark-accesses-to-rcu_state.n_force_qs.patch
 mac80211-fix-regression-in-ssn-handling-of-addba-tx.patch
 net-sched-fix-suspicious-rcu-usage-while-accessing-tcf_tunnel_info.patch
+revert-xsk-do-not-sleep-in-poll-when-need_wakeup-set.patch