As warned by smatch: drivers/media/usb/uvc/uvc_v4l2.c:911 uvc_ioctl_g_input() error: doing dma on the stack (&i) drivers/media/usb/uvc/uvc_v4l2.c:943 uvc_ioctl_s_input() error: doing dma on the stack (&i) those two functions call uvc_query_ctrl passing a pointer to a data at the DMA stack. those are used to send URBs via usb_control_msg(). Using DMA stack is not supported and should not work anymore on modern Linux versions. So, use a temporary buffer, allocated together with struct uvc_video_chain. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> --- drivers/media/usb/uvc/uvc_v4l2.c | 10 ++++------ drivers/media/usb/uvc/uvcvideo.h | 3 +++ 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c index 252136cc885c..e60d4675881a 100644 --- a/drivers/media/usb/uvc/uvc_v4l2.c +++ b/drivers/media/usb/uvc/uvc_v4l2.c @@ -900,7 +900,6 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input) struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; int ret; - u8 i; if (chain->selector == NULL || (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) { @@ -910,11 +909,11 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input) ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, chain->selector->id, chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, - &i, 1); + &chain->input, 1); if (ret < 0) return ret; - *input = i - 1; + *input = chain->input - 1; return 0; } @@ -923,7 +922,6 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input) struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; int ret; - u32 i; ret = uvc_acquire_privileges(handle); if (ret < 0) @@ -939,10 +937,10 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input) if (input >= chain->selector->bNrInPins) return -EINVAL; - i = input + 1; + chain->input = input + 1; return uvc_query_ctrl(chain->dev, UVC_SET_CUR, chain->selector->id, chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, - &i, 1); + &chain->input, 1); } static int uvc_ioctl_queryctrl(struct file *file, void *fh, diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h index cce5e38133cd..3c0ed90d6912 100644 --- a/drivers/media/usb/uvc/uvcvideo.h +++ b/drivers/media/usb/uvc/uvcvideo.h @@ -475,6 +475,9 @@ struct uvc_video_chain { struct mutex ctrl_mutex; /* Protects ctrl.info */ struct v4l2_prio_state prio; /* V4L2 priority state */ + + u8 input; /* buffer for set/get input */ + u32 caps; /* V4L2 chain-wide caps */ }; -- 2.31.1