From 1f7f504dcd9d1262437bdcf4fa071e41dec1af03 Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Tue, 24 Sep 2019 18:45:38 +0000 Subject: can: rx-offload: can_rx_offload_irq_offload_fifo(): continue on error In case of a resource shortage, i.e. the rx_offload queue will overflow or a skb fails to be allocated (due to OOM), can_rx_offload_offload_one() will call mailbox_read() to discard the mailbox and return an ERR_PTR. If the hardware FIFO is empty can_rx_offload_offload_one() will return NULL. In case a CAN frame was read from the hardware, can_rx_offload_offload_one() returns the skb containing it. Without this patch can_rx_offload_irq_offload_fifo() bails out if no skb returned, regardless of the reason. Similar to can_rx_offload_irq_offload_timestamp() in case of a resource shortage the whole FIFO should be discarded, to avoid an IRQ storm and give the system some time to recover. However if the FIFO is empty the loop can be left. With this patch the loop is left in case of empty FIFO, but not on errors. Signed-off-by: Marc Kleine-Budde --- drivers/net/can/rx-offload.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers/net/can/rx-offload.c') diff --git a/drivers/net/can/rx-offload.c b/drivers/net/can/rx-offload.c index 2ea8676579a9..84cae167e42f 100644 --- a/drivers/net/can/rx-offload.c +++ b/drivers/net/can/rx-offload.c @@ -248,7 +248,9 @@ int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload) while (1) { skb = can_rx_offload_offload_one(offload, 0); - if (IS_ERR_OR_NULL(skb)) + if (IS_ERR(skb)) + continue; + if (!skb) break; skb_queue_tail(&offload->skb_queue, skb); -- cgit