staging: ath6kl: Fixing a race condition during initialization

The commit fixes a race condition in the initialization portion of the
driver. The problem was observed while testing with the kernel in the
staging-next tree. The wait on the ready event is signalled prematurely
before setting the arVersion.wlan_ver and arVersion.abi_ver. The code
waiting on this semaphore checks for the validity of these values and
hence may proceed with an un-updated values of these fields. The wakeup
signal is now sent after these values are set.

Signed-off-by: Vipin Mehta <vmehta@atheros.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Vipin Mehta 2010-09-17 09:55:15 -07:00 committed by Greg Kroah-Hartman
parent 103281df0b
commit 9b906a33e0
1 changed files with 4 additions and 2 deletions

View File

@ -4170,8 +4170,6 @@ ar6000_ready_event(void *devt, A_UINT8 *datap, A_UINT8 phyCap, A_UINT32 sw_ver,
AR_SOFTC_T *ar = (AR_SOFTC_T *)devt;
struct net_device *dev = ar->arNetDev;
ar->arWmiReady = TRUE;
wake_up(&arEvent);
A_MEMCPY(dev->dev_addr, datap, AR6000_ETH_ADDR_LEN);
AR_DEBUG_PRINTF(ATH_DEBUG_INFO,("mac address = %2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x\n",
dev->dev_addr[0], dev->dev_addr[1],
@ -4182,6 +4180,10 @@ ar6000_ready_event(void *devt, A_UINT8 *datap, A_UINT8 phyCap, A_UINT32 sw_ver,
ar->arVersion.wlan_ver = sw_ver;
ar->arVersion.abi_ver = abi_ver;
/* Indicate to the waiting thread that the ready event was received */
ar->arWmiReady = TRUE;
wake_up(&arEvent);
#if WLAN_CONFIG_IGNORE_POWER_SAVE_FAIL_EVENT_DURING_SCAN
wmi_pmparams_cmd(ar->arWmi, 0, 1, 0, 0, 1, IGNORE_POWER_SAVE_FAIL_EVENT_DURING_SCAN);
#endif