50 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
From: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
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Date: Wed, 30 Nov 2016 10:59:29 +0530
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Subject: [PATCH] ath10k: Fix soft lockup during firmware crash/hw-restart
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During firmware crash (or) user requested manual restart
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the system gets into a soft lock up state because of the
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below root cause.
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During user requested hardware restart / firmware crash
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the system goes into a soft lockup state as 'napi_synchronize'
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is called after 'napi_disable' (which sets 'NAPI_STATE_SCHED'
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bit) and it sleeps into infinite loop as it waits for
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'NAPI_STATE_SCHED' to be cleared. This condition is hit because
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'ath10k_hif_stop' is called twice as below (resulting in calling
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'napi_synchronize' after 'napi_disable')
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'ath10k_core_restart' -> 'ath10k_hif_stop' (ATH10K_STATE_ON) ->
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-> 'ieee80211_restart_hw' -> 'ath10k_start' -> 'ath10k_halt' ->
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'ath10k_core_stop' -> 'ath10k_hif_stop' (ATH10K_STATE_RESTARTING)
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Fix this by calling 'ath10k_halt' in ath10k_core_restart itself
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as it makes more sense before informing mac80211 to restart h/w
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Also remove 'ath10k_halt' in ath10k_start for the state of 'restarting'
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Fixes: 3c97f5de1f28 ("ath10k: implement NAPI support")
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Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
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---
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--- a/drivers/net/wireless/ath/ath10k/core.c
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+++ b/drivers/net/wireless/ath/ath10k/core.c
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@@ -1534,7 +1534,7 @@ static void ath10k_core_restart(struct w
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 	switch (ar->state) {
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 	case ATH10K_STATE_ON:
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 		ar->state = ATH10K_STATE_RESTARTING;
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-		ath10k_hif_stop(ar);
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+		ath10k_halt(ar);
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 		ath10k_scan_finish(ar);
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 		ieee80211_restart_hw(ar->hw);
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 		break;
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--- a/drivers/net/wireless/ath/ath10k/mac.c
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+++ b/drivers/net/wireless/ath/ath10k/mac.c
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@@ -4470,7 +4470,6 @@ static int ath10k_start(struct ieee80211
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 		ar->state = ATH10K_STATE_ON;
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 		break;
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 	case ATH10K_STATE_RESTARTING:
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-		ath10k_halt(ar);
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 		ar->state = ATH10K_STATE_RESTARTED;
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 		break;
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 	case ATH10K_STATE_ON:
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