Hi,
On Thu, May 21, 2020 at 03:35:47PM +0800, Dinghao Liu wrote:
> When copy_from_user() returns an error code, a pairing
> runtime PM usage counter decrement is needed to keep
> the counter balanced.
>
> Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
> ---
> drivers/usb/musb/musb_debugfs.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/musb/musb_debugfs.c b/drivers/usb/musb/musb_debugfs.c
> index 7b6281ab62ed..837c38a5e4ef 100644
> --- a/drivers/usb/musb/musb_debugfs.c
> +++ b/drivers/usb/musb/musb_debugfs.c
> @@ -178,8 +178,11 @@ static ssize_t musb_test_mode_write(struct file *file,
>
> memset(buf, 0x00, sizeof(buf));
>
> - if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
> + if (copy_from_user(buf, ubuf, min_t(size_t, sizeof(buf) - 1, count))) {
> + pm_runtime_mark_last_busy(musb->controller);
> + pm_runtime_put_autosuspend(musb->controller);
> return -EFAULT;
> + }
Thanks for catching the bug. Can you please instead move these lines to
the beginning of this function so that pm_runtime_get_sync() is not
called if copy_from_user() failed?
-Bin.
