From 59979af1449b21fcfa9b3e80651d5dcb5c88ff43 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Wed, 31 May 2017 13:19:10 +0200
Subject: [PATCH 115/146] iwlwifi: pcie: warn if paging is already initialized
 during init
Git-commit: f0fea2b728af737ec45d96a0279087a558ad9774
Patch-mainline: v4.13-rc1
References: FATE#322675

This appears to happen in some cases, like when iwlmvm is unloaded and
loaded again without also unloading iwlwifi. Warn in this case and free
the paging data to be able to continue without causing corruption and
kernel crashes due to it (otherwise, paging data is overwritten, but
dram->paging_cnt gets to be twice as big as it should be, and then an
eventual free will crash.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info.c b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info.c
index 00d1a5f048b3..eddaca76d514 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info.c
@@ -137,6 +137,11 @@ static int iwl_pcie_ctxt_info_init_fw_sec(struct iwl_trans *trans,
 	struct iwl_context_info_dram *ctxt_dram = &ctxt_info->dram;
 	int i, ret, lmac_cnt, umac_cnt, paging_cnt;
 
+	if (WARN(dram->paging,
+		 "paging shouldn't already be initialized (%d pages)\n",
+		 dram->paging_cnt))
+		iwl_pcie_ctxt_info_free_paging(trans);
+
 	lmac_cnt = iwl_pcie_get_num_sections(fw, 0);
 	/* add 1 due to separator */
 	umac_cnt = iwl_pcie_get_num_sections(fw, lmac_cnt + 1);
-- 
2.12.3