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To workaround the issue, lets retry vb2_reqbufs() with > vb_vmalloc_memops if it fails to allocate buffer with vb2_dma_sg_memops. > > Link[1]: https://lore.kernel.org/linux-media/20230828075420.2009568-1-anle.pan@nxp.com/ > Link[2]: https://lore.kernel.org/linux-media/20230914145812.12851-1-hui.fang@nxp.com/ > Signed-off-by: Xu Yang > --- > drivers/usb/gadget/function/uvc_queue.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/usb/gadget/function/uvc_queue.c b/drivers/usb/gadget/function/uvc_queue.c > index 21d80322cb6148ed87eb77f453a1f1644e4923ae..586e5524c171f115d98af5dda43fb800466f46d2 100644 > --- a/drivers/usb/gadget/function/uvc_queue.c > +++ b/drivers/usb/gadget/function/uvc_queue.c > @@ -182,7 +182,15 @@ int uvcg_alloc_buffers(struct uvc_video_queue *queue, > { > int ret; > > +retry: > ret = vb2_reqbufs(&queue->queue, rb); > + if (ret < 0 && queue->use_sg) { > + uvc_trace(UVC_TRACE_IOCTL, > + "failed to alloc buffer with sg enabled, try non-sg mode\n"); > + queue->use_sg = 0; > + queue->queue.mem_ops = &vb2_vmalloc_memops; How it work if dma_sg_alloc() failure, vmalloc success, follow dma_map() should be failure for vmalloc() Frank > + goto retry; > + } > > return ret ? ret : rb->count; > } > > -- > 2.34.1 >