diff options
| author | Alexey Khoroshilov <khoroshilov@ispras.ru> | 2013-07-02 00:43:42 +0400 |
|---|---|---|
| committer | John W. Linville <linville@tuxdriver.com> | 2013-07-17 14:34:49 -0400 |
| commit | 9494849e53e74048ee14d512feade01db402eef7 (patch) | |
| tree | a7385029e763f93f3dc5d33c3ded13e3ac583470 | |
| parent | a4943ccbc316fd74d3612d7a5984a91ab7e5dc8c (diff) | |
ath9k_htc: fix data race between request_firmware_nowait() callback and suspend()
ath9k_hif_usb_probe() requests firmware asynchronically and
there is some initialization postponed till firmware is ready.
In particular, ath9k_hif_usb_firmware_cb() callback initializes
hif_dev->tx.tx_buf and hif_dev->tx.tx_pending lists.
At the same time, ath9k_hif_usb_suspend() iterates that lists through
ath9k_hif_usb_dealloc_urbs(). If suspend happens before request_firmware_nowait()
callback is called, it can lead to oops.
Similar issue could be in ath9k_hif_usb_disconnect(), but it is prevented
using hif_dev->fw_done completion and HIF_USB_READY flag. The patch extends
this approach to suspend() as well.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/hif_usb.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c index 9e582e14da74..2469db5a5bb1 100644 --- a/drivers/net/wireless/ath/ath9k/hif_usb.c +++ b/drivers/net/wireless/ath/ath9k/hif_usb.c @@ -1082,7 +1082,7 @@ static void ath9k_hif_usb_firmware_fail(struct hif_device_usb *hif_dev) struct device *dev = &hif_dev->udev->dev; struct device *parent = dev->parent; - complete(&hif_dev->fw_done); + complete_all(&hif_dev->fw_done); if (parent) device_lock(parent); @@ -1131,7 +1131,7 @@ static void ath9k_hif_usb_firmware_cb(const struct firmware *fw, void *context) release_firmware(fw); hif_dev->flags |= HIF_USB_READY; - complete(&hif_dev->fw_done); + complete_all(&hif_dev->fw_done); return; @@ -1316,7 +1316,10 @@ static int ath9k_hif_usb_suspend(struct usb_interface *interface, if (!(hif_dev->flags & HIF_USB_START)) ath9k_htc_suspend(hif_dev->htc_handle); - ath9k_hif_usb_dealloc_urbs(hif_dev); + wait_for_completion(&hif_dev->fw_done); + + if (hif_dev->flags & HIF_USB_READY) + ath9k_hif_usb_dealloc_urbs(hif_dev); return 0; } |