Patch "brcmfmac: unbind all devices upon failure in firmware callback" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

brcmfmac: unbind all devices upon failure in firmware callback

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
brcmfmac-unbind-all-devices-upon-failure-in-firmware-callback.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Arend Van Spriel <[email protected]>
Date: Mon, 12 Jun 2017 12:47:34 +0100
Subject: brcmfmac: unbind all devices upon failure in firmware callback

From: Arend Van Spriel <[email protected]>

commit 7a51461fc2da82a6c565a3ee65c41c197f28225d upstream.

When request firmware fails, brcmf_ops_sdio_remove is being called and brcmf_bus freed. In such circumstancies if you do a suspend/resume cycle the kernel hangs on resume due a NULL pointer dereference in resume function. So in brcmf_sdio_firmware_callback() we need to unbind the driver from both sdio_func devices when firmware load failure is indicated.

---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

@@ -3985,14 +3985,14 @@ static void brcmf_sdio_firmware_callback
 	u8 saveclk;
 
 	brcmf_dbg(TRACE, "Enter: dev=%s, err=%d\n", dev_name(dev), err);
+	bus_if = dev_get_drvdata(dev);
+	sdiodev = bus_if->bus_priv.sdio;
 	if (err)
 		goto fail;
 
-	bus_if = dev_get_drvdata(dev);
 	if (!bus_if->drvr)
 		return;
 
-	sdiodev = bus_if->bus_priv.sdio;
 	bus = sdiodev->bus;
 
 	/* try to download image and nvram to the dongle */

@@ -4081,6 +4081,7 @@ release:
 fail:
 	brcmf_dbg(TRACE, "failed: dev=%s, err=%d\n", dev_name(dev), err);
 	device_release_driver(dev);
+	device_release_driver(&sdiodev->func[2]->dev);
 }
 
 struct brcmf_sdio *brcmf_sdio_probe(struct brcmf_sdio_dev *sdiodev)

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/brcmfmac-use-firmware-callback-upon-failure-to-load.patch queue-4.9/brcmfmac-add-parameter-to-pass-error-code-in-firmware-callback.patch queue-4.9/brcmfmac-unbind-all-devices-upon-failure-in-firmware-callback.patch