[3.19.y-ckt stable] Patch "iwlwifi: mvm: don't allow sched scans without matches to be started" has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

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

    iwlwifi: mvm: don't allow sched scans without matches to be started

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt16.

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

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

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

>From 4211a325376e2e9f445fcdcc3987ba8a482f18bc Mon Sep 17 00:00:00 2001
From: Luca Coelho <luciano.coelho at intel.com>
Date: Tue, 2 Feb 2016 15:11:15 +0200
Subject: iwlwifi: mvm: don't allow sched scans without matches to be started

commit 5e56276e7555b34550d51459a801ff75eca8b907 upstream.

The firmware can perform a scheduled scan with not matchsets passed,
but it can't send notification that results were found.  Since the
userspace then cannot know when we got new results and the firmware
wouldn't trigger a wake in case we are sleeping, it's better not to
allow scans without matchsets.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=110831

Signed-off-by: Luca Coelho <luciano.coelho at intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach at intel.com>
[ kamal: backport to 3.19-stable: context ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/net/wireless/iwlwifi/mvm/scan.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/iwlwifi/mvm/scan.c b/drivers/net/wireless/iwlwifi/mvm/scan.c
index 844bf7c..9807146 100644
--- a/drivers/net/wireless/iwlwifi/mvm/scan.c
+++ b/drivers/net/wireless/iwlwifi/mvm/scan.c
@@ -1015,6 +1015,10 @@ int iwl_mvm_sched_scan_start(struct iwl_mvm *mvm,
 		.schedule_line[1].full_scan_mul = IWL_FULL_SCAN_MULTIPLIER,
 	};

+	/* we don't support "match all" in the firmware */
+	if (!req->n_match_sets)
+		return -EOPNOTSUPP;
+
 	if (iwl_mvm_scan_pass_all(mvm, req))
 		scan_req.flags |= cpu_to_le16(IWL_SCAN_OFFLOAD_FLAG_PASS_ALL);

--
2.7.0