diff options
Diffstat (limited to 'features/rt/net-Dequeue-in-dev_cpu_dead-without-the-lock.patch')
| -rw-r--r-- | features/rt/net-Dequeue-in-dev_cpu_dead-without-the-lock.patch | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/features/rt/net-Dequeue-in-dev_cpu_dead-without-the-lock.patch b/features/rt/net-Dequeue-in-dev_cpu_dead-without-the-lock.patch new file mode 100644 index 00000000..81ff8d7a --- /dev/null +++ b/features/rt/net-Dequeue-in-dev_cpu_dead-without-the-lock.patch @@ -0,0 +1,36 @@ +From 792214a4ddc6c2bca52779e1665f52c5587868f9 Mon Sep 17 00:00:00 2001 +From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +Date: Wed, 16 Sep 2020 16:15:39 +0200 +Subject: [PATCH 142/191] net: Dequeue in dev_cpu_dead() without the lock + +Upstream uses skb_dequeue() to acquire lock of `input_pkt_queue'. The reason is +to synchronize against a remote CPU which still thinks that the CPU is online +enqueues packets to this CPU. +There are no guarantees that the packet is enqueued before the callback is run, +it just hope. +RT however complains about an not initialized lock because it uses another lock +for `input_pkt_queue' due to the IRQ-off nature of the context. + +Use the unlocked dequeue version for `input_pkt_queue'. + +Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> +--- + net/core/dev.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/net/core/dev.c b/net/core/dev.c +index 16c9aa19ede2..aab963be5655 100644 +--- a/net/core/dev.c ++++ b/net/core/dev.c +@@ -11162,7 +11162,7 @@ static int dev_cpu_dead(unsigned int oldcpu) + netif_rx_ni(skb); + input_queue_head_incr(oldsd); + } +- while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) { ++ while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) { + netif_rx_ni(skb); + input_queue_head_incr(oldsd); + } +-- +2.19.1 + |