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    Subject[PATCH 4.4 12/80] usb: gadget: r8a66597: Fix two possible sleep-in-atomic-context bugs in init_controller()
    Date
    4.4-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Jia-Ju Bai <baijiaju1990@gmail.com>

    [ Upstream commit 0602088b10a7c0b4e044a810678ef93d7cc5bf48 ]

    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>
    Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
    Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    drivers/usb/gadget/udc/r8a66597-udc.c | 4 ++--
    1 file changed, 2 insertions(+), 2 deletions(-)

    --- a/drivers/usb/gadget/udc/r8a66597-udc.c
    +++ b/drivers/usb/gadget/udc/r8a66597-udc.c
    @@ -835,11 +835,11 @@ static void init_controller(struct r8a66

    r8a66597_bset(r8a66597, XCKE, SYSCFG0);

    - msleep(3);
    + mdelay(3);

    r8a66597_bset(r8a66597, PLLC, SYSCFG0);

    - msleep(1);
    + mdelay(1);

    r8a66597_bset(r8a66597, SCKE, SYSCFG0);


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