From: Fabio Estevam festevam@denx.de
[ Upstream commit 019edd01d174ce4bb2e517dd332922514d176601 ]
On a i.MX-based board with a QCA9377 Wifi chip, the following errors are seen after launching the 'hostapd' application:
hostapd /etc/wifi.conf Configuration file: /etc/wifi.conf wlan0: interface state UNINITIALIZED->COUNTRY_UPDATE NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! Using interface wlan0 with hwaddr 00:1f:7b:31:04:a0 and ssid "thessid" IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready wlan0: interface state COUNTRY_UPDATE->ENABLED wlan0: AP-ENABLED NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! ...
Fix this problem by adding the BH locking around napi-schedule(), in the same way it was done in commit e63052a5dd3c ("mlx5e: add add missing BH locking around napi_schdule()").
Its commit log provides the following explanation:
"It's not correct to call napi_schedule() in pure process context. Because we use __raise_softirq_irqoff() we require callers to be in a context which will eventually lead to softirq handling (hardirq, bh disabled, etc.).
With code as is users will see:
NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!! "
Fixes: cfee8793a74d ("ath10k: enable napi on RX path for sdio") Signed-off-by: Fabio Estevam festevam@denx.de Signed-off-by: Kalle Valo kvalo@codeaurora.org Link: https://lore.kernel.org/r/20210824144339.2796122-1-festevam@denx.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/ath/ath10k/sdio.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/ath/ath10k/sdio.c b/drivers/net/wireless/ath/ath10k/sdio.c index b746052737e0b..eb705214f3f0a 100644 --- a/drivers/net/wireless/ath/ath10k/sdio.c +++ b/drivers/net/wireless/ath/ath10k/sdio.c @@ -1363,8 +1363,11 @@ static void ath10k_rx_indication_async_work(struct work_struct *work) ep->ep_ops.ep_rx_complete(ar, skb); }
- if (test_bit(ATH10K_FLAG_CORE_REGISTERED, &ar->dev_flags)) + if (test_bit(ATH10K_FLAG_CORE_REGISTERED, &ar->dev_flags)) { + local_bh_disable(); napi_schedule(&ar->napi); + local_bh_enable(); + } }
static int ath10k_sdio_read_rtc_state(struct ath10k_sdio *ar_sdio, unsigned char *state)