Messages in this thread Patch in this message | | | From | Jia-Ju Bai <> | Subject | [PATCH 1/2] usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller() | Date | Wed, 20 Jun 2018 11:54:53 +0800 |
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The driver may sleep with holding a spinlock. The function call paths (from bottom to top) in Linux-4.16.7 are:
[FUNC] msleep drivers/usb/gadget/udc/r8a66597-udc.c, 839: msleep in init_controller drivers/usb/gadget/udc/r8a66597-udc.c, 96: init_controller in r8a66597_usb_disconnect drivers/usb/gadget/udc/r8a66597-udc.c, 93: spin_lock in r8a66597_usb_disconnect
[FUNC] msleep drivers/usb/gadget/udc/r8a66597-udc.c, 835: msleep in init_controller drivers/usb/gadget/udc/r8a66597-udc.c, 96: init_controller in r8a66597_usb_disconnect drivers/usb/gadget/udc/r8a66597-udc.c, 93: spin_lock in r8a66597_usb_disconnect
To fix these bugs, msleep() is replaced with mdelay().
This bug is found by my static analysis tool (DSAC-2) and checked by my code review.
Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> --- drivers/usb/gadget/udc/r8a66597-udc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/gadget/udc/r8a66597-udc.c b/drivers/usb/gadget/udc/r8a66597-udc.c index a3ecce62662b..24ee9867964b 100644 --- a/drivers/usb/gadget/udc/r8a66597-udc.c +++ b/drivers/usb/gadget/udc/r8a66597-udc.c @@ -832,11 +832,11 @@ static void init_controller(struct r8a66597 *r8a66597) r8a66597_bset(r8a66597, XCKE, SYSCFG0); - msleep(3); + mdelay(3); r8a66597_bset(r8a66597, PLLC, SYSCFG0); - msleep(1); + mdelay(1); r8a66597_bset(r8a66597, SCKE, SYSCFG0); -- 2.17.0
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