From 2dcfbdd702fa503ac5d1449fce1f422bf2aabd19 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Thu, 5 Dec 2019 17:46:42 +0100
Subject: [PATCH] mt76: disable bh in mt76_dma_rx_poll

Fixes potential RCU issues and avoids calling ieee80211_rx_napi with softirq
enabled.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 dma.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dma.c b/dma.c
index 6fa780d2..45a58042 100644
--- a/dma.c
+++ b/dma.c
@@ -528,6 +528,7 @@ mt76_dma_rx_poll(struct napi_struct *napi, int budget)
 	dev = container_of(napi->dev, struct mt76_dev, napi_dev);
 	qid = napi - dev->napi;
 
+	local_bh_disable();
 	rcu_read_lock();
 
 	do {
@@ -537,6 +538,7 @@ mt76_dma_rx_poll(struct napi_struct *napi, int budget)
 	} while (cur && done < budget);
 
 	rcu_read_unlock();
+	local_bh_enable();
 
 	if (done < budget && napi_complete(napi))
 		dev->drv->rx_poll_complete(dev, qid);