Patch "ath10k: fix kernel panic, move arvifs list head init before htt init" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

ath10k: fix kernel panic, move arvifs list head init before htt init

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ath10k-fix-kernel-panic-move-arvifs-list-head-init-before-htt-init.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Anilkumar Kolli <[email protected]>
Date: Tue, 26 Apr 2016 21:35:48 +0530
Subject: ath10k: fix kernel panic, move arvifs list head init before htt init

From: Anilkumar Kolli <[email protected]>

commit 4ad24a9d83bd4bf0a85e95bf144e18d3fda4fbf1 upstream.

It is observed that while loading and unloading ath10k modules in an infinite loop, before ath10k_core_start() completion HTT rx frames are received, while processing these frames, dereferencing the arvifs list code is getting hit before initilizing the arvifs list, causing a kernel panic.

This patch initilizes the arvifs list before initilizing htt.

Fixes the below issue:
[<bf88b058>] (ath10k_htt_rx_pktlog_completion_handler+0x278/0xd08 [ath10k_core]) [<bf88b058>] (ath10k_htt_rx_pktlog_completion_handler [ath10k_core]) [<bf88c0dc>] (ath10k_htt_txrx_compl_task+0x5f4/0xeb0 [ath10k_core]) [<bf88c0dc>] (ath10k_htt_txrx_compl_task [ath10k_core]) [<c0234100>] (tasklet_action+0x8c/0xec)
[<c0234100>] (tasklet_action)
[<c02337c0>] (__do_softirq+0xf8/0x228)
[<c02337c0>] (__do_softirq) [<c0233920>] (run_ksoftirqd+0x30/0x90)

 Code: e5954ad8 e2899008 e1540009 0a00000d (e5943008)
 ---[ end trace 71de5c2e011dbf56 ]---
 Kernel panic - not syncing: Fatal exception in interrupt

---
 drivers/net/wireless/ath/ath10k/core.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

@@ -1681,6 +1681,10 @@ int ath10k_core_start(struct ath10k *ar,
 		goto err_hif_stop;
 	}
 
+	ar->free_vdev_map = (1LL << ar->max_num_vdevs) - 1;
+
+	INIT_LIST_HEAD(&ar->arvifs);
+
 	/* we don't care about HTT in UTF mode */
 	if (mode == ATH10K_FIRMWARE_MODE_NORMAL) {
 		status = ath10k_htt_setup(&ar->htt);

@@ -1694,10 +1698,6 @@ int ath10k_core_start(struct ath10k *ar,
 	if (status)
 		goto err_hif_stop;
 
-	ar->free_vdev_map = (1LL << ar->max_num_vdevs) - 1;
-
-	INIT_LIST_HEAD(&ar->arvifs);
-
 	return 0;
 
 err_hif_stop:

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/ath10k-fix-debugfs-pktlog_filter-write.patch queue-4.4/ath10k-fix-kernel-panic-move-arvifs-list-head-init-before-htt-init.patch