openwrt/target/linux/generic/backport-5.4/080-wireguard-0099-wireguard-send-receive-cond_resched-when-processing-.patch
Jason A. Donenfeld 196f3d586f kernel-5.4: bump to 5.4.102 and refresh patches
5.4.102 backported a lot of stuff that our WireGuard backport already
did, in addition to other patches we had, so those patches were
removed from that part of the series. In the process other patches were
refreshed or reworked to account for upstream changes.

This commit involved `update_kernel.sh -v -u 5.4`.

Cc: John Audia <graysky@archlinux.us>
Cc: David Bauer <mail@david-bauer.net>
Cc: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2021-03-04 22:06:53 +01:00

59 lines
2.0 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Wed, 6 May 2020 15:33:04 -0600
Subject: [PATCH] wireguard: send/receive: cond_resched() when processing
worker ringbuffers
commit 4005f5c3c9d006157ba716594e0d70c88a235c5e upstream.
Users with pathological hardware reported CPU stalls on CONFIG_
PREEMPT_VOLUNTARY=y, because the ringbuffers would stay full, meaning
these workers would never terminate. That turned out not to be okay on
systems without forced preemption, which Sultan observed. This commit
adds a cond_resched() to the bottom of each loop iteration, so that
these workers don't hog the core. Note that we don't need this on the
napi poll worker, since that terminates after its budget is expended.
Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
Reported-by: Wang Jian <larkwang@gmail.com>
Fixes: e7096c131e51 ("net: WireGuard secure network tunnel")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
drivers/net/wireguard/receive.c | 2 ++
drivers/net/wireguard/send.c | 4 ++++
2 files changed, 6 insertions(+)
--- a/drivers/net/wireguard/receive.c
+++ b/drivers/net/wireguard/receive.c
@@ -516,6 +516,8 @@ void wg_packet_decrypt_worker(struct wor
&PACKET_CB(skb)->keypair->receiving)) ?
PACKET_STATE_CRYPTED : PACKET_STATE_DEAD;
wg_queue_enqueue_per_peer_napi(skb, state);
+ if (need_resched())
+ cond_resched();
}
}
--- a/drivers/net/wireguard/send.c
+++ b/drivers/net/wireguard/send.c
@@ -281,6 +281,8 @@ void wg_packet_tx_worker(struct work_str
wg_noise_keypair_put(keypair, false);
wg_peer_put(peer);
+ if (need_resched())
+ cond_resched();
}
}
@@ -304,6 +306,8 @@ void wg_packet_encrypt_worker(struct wor
}
wg_queue_enqueue_per_peer(&PACKET_PEER(first)->tx_queue, first,
state);
+ if (need_resched())
+ cond_resched();
}
}