This is a note to let you know that I've just added the patch titled
iwlwifi: mvm: don't use transmit queue hang detection when it is not possible
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: iwlwifi-mvm-don-t-use-transmit-queue-hang-detection-when-it-is-not-possible.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From 0b9832b712d6767d6c7b01965fd788d1ca84fc92 Mon Sep 17 00:00:00 2001
From: Emmanuel Grumbach emmanuel.grumbach@intel.com Date: Mon, 13 Nov 2017 09:50:47 +0200 Subject: iwlwifi: mvm: don't use transmit queue hang detection when it is not possible
From: Emmanuel Grumbach emmanuel.grumbach@intel.com
commit 0b9832b712d6767d6c7b01965fd788d1ca84fc92 upstream.
When we act as an AP, new firmware versions handle internally the power saving clients and the driver doesn't know that the peers went to sleep. It is, hence, possible that a peer goes to sleep for a long time and stop pulling frames. This will cause its transmit queue to hang which is a condition that triggers the recovery flow in the driver.
While this client is certainly buggy (it should have pulled the frame based on the TIM IE in the beacon), we can't blow up because of a buggy client.
Change the current implementation to not enable the transmit queue hang detection on queues that serve peers when we act as an AP / GO.
We can still enable this mechanism using the debug configuration which can come in handy when we want to debug why the client doesn't wake up.
Signed-off-by: Emmanuel Grumbach emmanuel.grumbach@intel.com Signed-off-by: Luca Coelho luciano.coelho@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/wireless/intel/iwlwifi/mvm/utils.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/utils.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/utils.c @@ -1143,9 +1143,18 @@ unsigned int iwl_mvm_get_wd_timeout(stru unsigned int default_timeout = cmd_q ? IWL_DEF_WD_TIMEOUT : mvm->cfg->base_params->wd_timeout;
- if (!iwl_fw_dbg_trigger_enabled(mvm->fw, FW_DBG_TRIGGER_TXQ_TIMERS)) + if (!iwl_fw_dbg_trigger_enabled(mvm->fw, FW_DBG_TRIGGER_TXQ_TIMERS)) { + /* + * We can't know when the station is asleep or awake, so we + * must disable the queue hang detection. + */ + if (fw_has_capa(&mvm->fw->ucode_capa, + IWL_UCODE_TLV_CAPA_STA_PM_NOTIF) && + vif && vif->type == NL80211_IFTYPE_AP) + return IWL_WATCHDOG_DISABLED; return iwlmvm_mod_params.tfd_q_hang_detect ? default_timeout : IWL_WATCHDOG_DISABLED; + }
trigger = iwl_fw_dbg_get_trigger(mvm->fw, FW_DBG_TRIGGER_TXQ_TIMERS); txq_timer = (void *)trigger->data;
Patches currently in stable-queue which might be from emmanuel.grumbach@intel.com are
queue-4.14/iwlwifi-mvm-fix-packet-injection.patch queue-4.14/iwlwifi-mvm-don-t-use-transmit-queue-hang-detection-when-it-is-not-possible.patch