This is a note to let you know that I've just added the patch titled usb: musb: ux500: Fix NULL pointer dereference at system PM to the 4.4-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: usb-musb-ux500-fix-null-pointer-dereference-at-system-pm.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 79c5623f1cb85f33403eb9f1e45124e9f56181f8 Mon Sep 17 00:00:00 2001 From: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Date: Mon, 25 Jan 2016 13:01:29 +0100 Subject: usb: musb: ux500: Fix NULL pointer dereference at system PM From: Ulf Hansson <ulf.hansson@xxxxxxxxxx> commit 79c5623f1cb85f33403eb9f1e45124e9f56181f8 upstream. The commit 7d32cdef5356 ("usb: musb: fail with error when no DMA controller set"), caused the core platform driver to correctly return an error code when fail probing. Unfurtante it also caused bug for a NULL pointer dereference, during system suspend for the ux500 driver. The reason is a lacking validation of the corresponding ->driver_data pointer, which won't be set when the musb core driver fails to probe (or haven't yet been probed). Fixes: 7d32cdef5356 ("usb: musb: fail with error when no DMA...") Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx> Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/musb/ux500.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/usb/musb/ux500.c +++ b/drivers/usb/musb/ux500.c @@ -348,7 +348,9 @@ static int ux500_suspend(struct device * struct ux500_glue *glue = dev_get_drvdata(dev); struct musb *musb = glue_to_musb(glue); - usb_phy_set_suspend(musb->xceiv, 1); + if (musb) + usb_phy_set_suspend(musb->xceiv, 1); + clk_disable_unprepare(glue->clk); return 0; @@ -366,7 +368,8 @@ static int ux500_resume(struct device *d return ret; } - usb_phy_set_suspend(musb->xceiv, 0); + if (musb) + usb_phy_set_suspend(musb->xceiv, 0); return 0; } Patches currently in stable-queue which might be from ulf.hansson@xxxxxxxxxx are queue-4.4/usb-musb-ux500-fix-null-pointer-dereference-at-system-pm.patch