[PATCH 3.19.y-ckt 028/146] rtlwifi: rtl8192cu: Fix kernel deadlock

From: Kamal Mostafa
Date: Wed Jun 17 2015 - 19:39:20 EST

3.19.8-ckt2 -stable review patch. If anyone has any objections, please let me know.


From: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

commit 414b7e3b9ce8b0577f613e656fdbc36b34b444dd upstream.

The USB mini-driver in rtlwifi, which is used by rtl8192cu, issues a call to
usb_control_msg() with a timeout value of 0. In some instances where the
interface is shutting down, this infinite wait results in a CPU deadlock. A
one second timeout fixes this problem without affecting any normal operations.

This bug is reported at https://bugzilla.novell.com/show_bug.cgi?id=927786.

Reported-by: Bernhard Wiedemann <bwiedemann@xxxxxxxx>
Tested-by: Bernhard Wiedemann <bwiedemann@xxxxxxxx>
Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
Cc: Bernhard Wiedemann <bwiedemann@xxxxxxxx>
Cc: Takashi Iwai<tiwai@xxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
drivers/net/wireless/rtlwifi/usb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/rtlwifi/usb.c b/drivers/net/wireless/rtlwifi/usb.c
index 46ee956..27cd6ca 100644
--- a/drivers/net/wireless/rtlwifi/usb.c
+++ b/drivers/net/wireless/rtlwifi/usb.c
@@ -126,7 +126,7 @@ static int _usbctrl_vendorreq_sync_read(struct usb_device *udev, u8 request,

do {
status = usb_control_msg(udev, pipe, request, reqtype, value,
- index, pdata, len, 0); /*max. timeout*/
+ index, pdata, len, 1000);
if (status < 0) {
/* firmware download is checksumed, don't retry */
if ((value >= FW_8192C_START_ADDRESS &&

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