[4.2.y-ckt stable] Patch "iwlwifi: pcie: properly configure the debug buffer size for 8000" has been added to the 4.2.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    iwlwifi: pcie: properly configure the debug buffer size for 8000

to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-4.2.y-queue

This patch is scheduled to be released in version 4.2.8-ckt3.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 4.2.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 3cf42f0d0b9c4af21360f14986ce1dfb699dfc10 Mon Sep 17 00:00:00 2001
From: Emmanuel Grumbach <emmanuel.grumbach at intel.com>
Date: Tue, 5 Jan 2016 15:25:43 +0200
Subject: iwlwifi: pcie: properly configure the debug buffer size for 8000

commit 62d7476d958ce06d7a10b02bdb30006870286fe2 upstream.

8000 device family has a new debug engine that needs to be
configured differently than 7000's.
The debug engine's DMA works in chunks of memory and the
size of the buffer really means the start of the last
chunk. Since one chunk is 256-byte long, we should
configure the device to write to buffer_size - 256.
This fixes a situation were the device would write to
memory it is not allowed to access.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach at intel.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/wireless/iwlwifi/pcie/trans.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/pcie/trans.c b/drivers/net/wireless/iwlwifi/pcie/trans.c
index dab9b91..444cdb9 100644
--- a/drivers/net/wireless/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/iwlwifi/pcie/trans.c
@@ -7,6 +7,7 @@
  *
  * Copyright(c) 2007 - 2015 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
+ * Copyright(c) 2016 Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -33,6 +34,7 @@
  *
  * Copyright(c) 2005 - 2015 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
+ * Copyright(c) 2016 Intel Deutschland GmbH
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -901,9 +903,16 @@ static void iwl_pcie_apply_destination(struct iwl_trans *trans)
 	if (dest->monitor_mode == EXTERNAL_MODE && trans_pcie->fw_mon_size) {
 		iwl_write_prph(trans, le32_to_cpu(dest->base_reg),
 			       trans_pcie->fw_mon_phys >> dest->base_shift);
-		iwl_write_prph(trans, le32_to_cpu(dest->end_reg),
-			       (trans_pcie->fw_mon_phys +
-				trans_pcie->fw_mon_size) >> dest->end_shift);
+		if (trans->cfg->device_family == IWL_DEVICE_FAMILY_8000)
+			iwl_write_prph(trans, le32_to_cpu(dest->end_reg),
+				       (trans_pcie->fw_mon_phys +
+					trans_pcie->fw_mon_size - 256) >>
+						dest->end_shift);
+		else
+			iwl_write_prph(trans, le32_to_cpu(dest->end_reg),
+				       (trans_pcie->fw_mon_phys +
+					trans_pcie->fw_mon_size) >>
+						dest->end_shift);
 	}
 }

--
1.9.1