commit ba5313f20ac96af7afe1b32469c29ba9a588b069
author Kamath Vinayak <c_vkamat@qti.qualcomm.com> Thu Aug 22 15:52:39 2013 +0530
committer Madan Mohan Koyyalamudi <mkoyyala@qca.qualcomm.com> Thu Aug 29 11:55:45 2013 -0700
tree 0f61ddaaeba6a297c2d8c980ef90560861f9ad46
parent df8aa819ae0af2457d7f1d4423d480d1b46d7a1d

wlan: Return success while stoping sched scan.

If driver unload is initiated with sched scan offloaded,
then driver is currently ignoring scan stop command with
failure, leading to access of released dev pointer saved in
sched scan req in rdev. Return success for sched scan
stop req during driver unload and logp in progress to
prevent the crash.

CRs-fixed: 532675
Change-Id: I0cbf79e98549948532a9d456bd616b094465dd74

CORE/HDD/src/wlan_hdd_cfg80211.c

diff --git a/CORE/HDD/src/wlan_hdd_cfg80211.c b/CORE/HDD/src/wlan_hdd_cfg80211.c
index 2c82d2f..66e3b55 100644
--- a/CORE/HDD/src/wlan_hdd_cfg80211.c
+++ b/CORE/HDD/src/wlan_hdd_cfg80211.c
@@ -7207,6 +7207,7 @@
     v_U32_t num_channels_allowed = WNI_CFG_VALID_CHANNEL_LIST_LEN;
     eHalStatus status = eHAL_STATUS_FAILURE;
     int result;
+    int ret = 0;
 
     if (NULL == pAdapter)
     {
@@ -7222,7 +7223,7 @@
     {
         VOS_TRACE( VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                    "%s: HDD context is not valid", __func__);
-        return result;
+        return -EINVAL;
     }
 
     hHal = WLAN_HDD_GET_HAL_CTX(pAdapter);
@@ -7238,7 +7239,7 @@
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_FATAL,
                   "%s: vos_mem_malloc failed", __func__);
-        return -ENODEV;
+        return -ENOMEM;
     }
 
     pPnoRequest->enable = 1; /*Enable PNO */
@@ -7249,6 +7250,7 @@
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                   "Network input is not correct");
+        ret = -EINVAL;
         goto error;
     }
 
@@ -7256,6 +7258,7 @@
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                   "Incorrect number of channels");
+        ret = -EINVAL;
         goto error;
     }
 
@@ -7266,6 +7269,7 @@
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                 "%s: failed to get valid channel list", __func__);
+        ret = -EINVAL;
         goto error;
     }
     /* Checking each channel against allowed channel list */
@@ -7294,6 +7298,7 @@
             VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                       "SSID Len %d is not correct for network %d",
                       pPnoRequest->aNetworks[i].ssId.length, i);
+            ret = -EINVAL;
             goto error;
         }
 
@@ -7325,12 +7330,13 @@
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                   "Failed to enable PNO");
+        ret = -EINVAL;
         goto error;
     }
 
 error:
     vos_mem_free(pPnoRequest);
-    return status;
+    return ret;
 }
 
 /*
@@ -7345,7 +7351,7 @@
     hdd_context_t *pHddCtx;
     tHalHandle hHal;
     tpSirPNOScanReq pPnoRequest = NULL;
-    int result;
+    int ret = 0;
 
     ENTER();
 
@@ -7357,13 +7363,35 @@
     }
 
     pHddCtx = WLAN_HDD_GET_CTX(pAdapter);
-    result = wlan_hdd_validate_context(pHddCtx);
 
-    if (0 != result)
+    if (NULL == pHddCtx)
     {
         VOS_TRACE( VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
-                   "%s: HDD context is not valid", __func__);
-        return result;
+                "%s: HDD context is Null", __func__);
+        return -ENODEV;
+    }
+
+    /* The return 0 is intentional when isLogpInProgress and
+     * isLoadUnloadInProgress. We did observe a crash due to a return of
+     * failure in sched_scan_stop , especially for a case where the unload
+     * of the happens at the same time. The function __cfg80211_stop_sched_scan
+     * was clearing rdev->sched_scan_req only when the sched_scan_stop returns
+     * success. If it returns a failure , then its next invocation due to the
+     * clean up of the second interface will have the dev pointer corresponding
+     * to the first one leading to a crash.
+     */
+    if (pHddCtx->isLogpInProgress)
+    {
+        VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
+                  "%s: LOGP in Progress. Ignore!!!", __func__);
+        return ret;
+    }
+
+    if (pHddCtx->isLoadUnloadInProgress)
+    {
+        VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
+                  "%s: Unloading/Loading in Progress. Ignore!!!", __func__);
+        return ret;
     }
 
     hHal = WLAN_HDD_GET_HAL_CTX(pAdapter);
@@ -7379,7 +7407,7 @@
     {
         VOS_TRACE( VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_FATAL,
                    "%s: vos_mem_malloc failed", __func__);
-        return -ENODEV;
+        return -ENOMEM;
     }
 
     memset(pPnoRequest, 0, sizeof (tSirPNOScanReq));
@@ -7393,12 +7421,13 @@
     {
         VOS_TRACE(VOS_MODULE_ID_HDD, VOS_TRACE_LEVEL_ERROR,
                   "Failed to disabled PNO");
+        ret = -EINVAL;
     }
 
     vos_mem_free(pPnoRequest);
 
     EXIT();
-    return status;
+    return ret;
 }
 
 #endif /*FEATURE_WLAN_SCAN_PNO*/