@@ -574,9 +574,12 @@ static void iwl_pcie_txq_unmap(struct iwl_trans *trans, int txq_id)
spin_lock_bh(&txq->lock);
while (q->write_ptr != q->read_ptr) {
+ IWL_DEBUG_TX_REPLY(trans, "Q %d Free %d\n",
+ txq_id, q->read_ptr);
iwl_pcie_txq_free_tfd(trans, txq, dma_dir);
q->read_ptr = iwl_queue_inc_wrap(q->read_ptr, q->n_bd);
}
+ txq->active = false;
spin_unlock_bh(&txq->lock);
}
@@ -907,6 +910,12 @@ void iwl_trans_pcie_reclaim(struct iwl_trans *trans, int txq_id, int ssn,
spin_lock(&txq->lock);
+ if (!txq->active) {
+ IWL_DEBUG_TX_QUEUES(trans, "Q %d inactive - ignoring idx %d\n",
+ txq_id, ssn);
+ goto out;
+ }
+
if (txq->q.read_ptr == tfd_num)
goto out;
@@ -1083,6 +1092,7 @@ void iwl_trans_pcie_txq_enable(struct iwl_trans *trans, int txq_id, int fifo,
(fifo << SCD_QUEUE_STTS_REG_POS_TXF) |
(1 << SCD_QUEUE_STTS_REG_POS_WSL) |
SCD_QUEUE_STTS_REG_MSK);
+ trans_pcie->txq[txq_id].active = true;
IWL_DEBUG_TX_QUEUES(trans, "Activate queue %d on FIFO %d WrPtr: %d\n",
txq_id, fifo, ssn & 0xff);
}
This is a note to let you know that I have just added a patch titled iwlwifi: pcie: fix race in queue unmapping to the linux-3.8.y-queue branch of the 3.8.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.8.y-queue This patch is scheduled to be released in version 3.8.13.5. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.8.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From b0a9ca7efcd0628810a833413c0fb00558e9ad38 Mon Sep 17 00:00:00 2001 From: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Date: Thu, 13 Jun 2013 11:45:59 +0300 Subject: iwlwifi: pcie: fix race in queue unmapping commit b967613d7e7c7bad176f5627c55e2d8c5aa2480e upstream. When a queue is disabled, it frees all its entries. Later, the op_mode might still get notifications from the firmware that triggers to free entries in the tx queue. The transport should be prepared for these races and know to ignore reclaim calls on queues that have been disabled and whose entries have been freed. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> [ kamal: backport to 3.8 (context) ] Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/net/wireless/iwlwifi/pcie/tx.c | 10 ++++++++++ 1 file changed, 10 insertions(+) -- 1.8.1.2