ath10k: fix a soft-lockup on firmware restart

Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Felix Fietkau 2016-12-13 12:52:16 +01:00
parent 7dcccacb98
commit 28f6951600
2 changed files with 51 additions and 2 deletions

View file

@ -0,0 +1,49 @@
From: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Date: Wed, 30 Nov 2016 10:59:29 +0530
Subject: [PATCH] ath10k: Fix soft lockup during firmware crash/hw-restart
During firmware crash (or) user requested manual restart
the system gets into a soft lock up state because of the
below root cause.
During user requested hardware restart / firmware crash
the system goes into a soft lockup state as 'napi_synchronize'
is called after 'napi_disable' (which sets 'NAPI_STATE_SCHED'
bit) and it sleeps into infinite loop as it waits for
'NAPI_STATE_SCHED' to be cleared. This condition is hit because
'ath10k_hif_stop' is called twice as below (resulting in calling
'napi_synchronize' after 'napi_disable')
'ath10k_core_restart' -> 'ath10k_hif_stop' (ATH10K_STATE_ON) ->
-> 'ieee80211_restart_hw' -> 'ath10k_start' -> 'ath10k_halt' ->
'ath10k_core_stop' -> 'ath10k_hif_stop' (ATH10K_STATE_RESTARTING)
Fix this by calling 'ath10k_halt' in ath10k_core_restart itself
as it makes more sense before informing mac80211 to restart h/w
Also remove 'ath10k_halt' in ath10k_start for the state of 'restarting'
Fixes: 3c97f5de1f28 ("ath10k: implement NAPI support")
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
---
--- a/drivers/net/wireless/ath/ath10k/core.c
+++ b/drivers/net/wireless/ath/ath10k/core.c
@@ -1534,7 +1534,7 @@ static void ath10k_core_restart(struct w
switch (ar->state) {
case ATH10K_STATE_ON:
ar->state = ATH10K_STATE_RESTARTING;
- ath10k_hif_stop(ar);
+ ath10k_halt(ar);
ath10k_scan_finish(ar);
ieee80211_restart_hw(ar->hw);
break;
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -4470,7 +4470,6 @@ static int ath10k_start(struct ieee80211
ar->state = ATH10K_STATE_ON;
break;
case ATH10K_STATE_RESTARTING:
- ath10k_halt(ar);
ar->state = ATH10K_STATE_RESTARTED;
break;
case ATH10K_STATE_ON:

View file

@ -1,6 +1,6 @@
--- a/drivers/net/wireless/ath/ath10k/mac.c
+++ b/drivers/net/wireless/ath/ath10k/mac.c
@@ -7815,6 +7815,21 @@ struct ath10k_vif *ath10k_get_arvif(stru
@@ -7812,6 +7812,21 @@ struct ath10k_vif *ath10k_get_arvif(stru
return arvif_iter.arvif;
}
@ -22,7 +22,7 @@
int ath10k_mac_register(struct ath10k *ar)
{
static const u32 cipher_suites[] = {
@@ -8048,6 +8063,12 @@ int ath10k_mac_register(struct ath10k *a
@@ -8045,6 +8060,12 @@ int ath10k_mac_register(struct ath10k *a
ar->hw->wiphy->cipher_suites = cipher_suites;
ar->hw->wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);