On Thu, Jan 21, 2021 at 06:59:08PM +0800, 慕冬亮 wrote: > > > rt2x00usb_vendor_request_buff(rt2x00dev, USB_MULTI_READ, > > > USB_VENDOR_REQUEST_IN, offset, > > > ®, sizeof(reg)); > > > > Are you sure this is valid to call this function with a variable on the > > stack like this? How did you test this change? > > First, I did not do any changes to this call. Second, the programming > style to pass the pointer of stack variable as arguments is not really > good. Third, I check this same code file, there are many code snippets > with such programming style. :( I know you did not change it, what I am asking is how did you test this change works? I think the kernel will warn you in huge ways that using this pointer on the stack is incorrect, which implies you did not test this change :( thanks, greg k-h