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From 99cedb045e358f0169da2993e3503179d041359c Mon Sep 17 00:00:00 2001 |
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From: Martin Willi <martin@strongswan.org> |
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Date: Wed, 22 Aug 2018 09:39:52 +0200 |
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Subject: [PATCH 080/145] ath10k: schedule hardware restart if WMI command |
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times out |
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|
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[ Upstream commit a9911937e7d332761e8c4fcbc7ba0426bdc3956f ] |
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|
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When running in AP mode, ath10k sometimes suffers from TX credit |
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starvation. The issue is hard to reproduce and shows up once in a |
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few days, but has been repeatedly seen with QCA9882 and a large |
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range of firmwares, including 10.2.4.70.67. |
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|
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Once the module is in this state, TX credits are never replenished, |
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which results in "SWBA overrun" errors, as no beacons can be sent. |
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Even worse, WMI commands run in a timeout while holding the conf |
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mutex for three seconds each, making any further operations slow |
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and the whole system unresponsive. |
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|
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The firmware/driver never recovers from that state automatically, |
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and triggering TX flush or warm restarts won't work over WMI. So |
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issue a hardware restart if a WMI command times out due to missing |
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TX credits. This implies a connectivity outage of about 1.4s in AP |
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mode, but brings back the interface and the whole system to a usable |
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state. WMI command timeouts have not been seen in absent of this |
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specific issue, so taking such drastic actions seems legitimate. |
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|
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Signed-off-by: Martin Willi <martin@strongswan.org> |
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Signed-off-by: Kalle Valo <kvalo@codeaurora.org> |
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Signed-off-by: Sasha Levin <sashal@kernel.org> |
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--- |
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drivers/net/wireless/ath/ath10k/wmi.c | 6 ++++++ |
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1 file changed, 6 insertions(+) |
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|
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diff --git a/drivers/net/wireless/ath/ath10k/wmi.c b/drivers/net/wireless/ath/ath10k/wmi.c |
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index 1dced0dae9cd..9f31b9a10850 100644 |
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--- a/drivers/net/wireless/ath/ath10k/wmi.c |
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+++ b/drivers/net/wireless/ath/ath10k/wmi.c |
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@@ -1869,6 +1869,12 @@ int ath10k_wmi_cmd_send(struct ath10k *ar, struct sk_buff *skb, u32 cmd_id) |
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if (ret) |
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dev_kfree_skb_any(skb); |
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|
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+ if (ret == -EAGAIN) { |
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+ ath10k_warn(ar, "wmi command %d timeout, restarting hardware\n", |
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+ cmd_id); |
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+ queue_work(ar->workqueue, &ar->restart_work); |
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+ } |
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+ |
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return ret; |
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} |
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|
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-- |
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2.19.1 |
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