When hcd->localmem_pool is non-null, localmem_pool is used to allocate DMA memory. In this case, the dma address will be properly returned (in dma_handle), and dma_mmap_coherent should be used to map this memory into the user space. However, the current implementation uses pfn_remap_range, which is supposed to map normal pages. Instead of repeating the logic in the memory allocation function, this patch introduces a more robust solution. Here, the type of allocated memory is checked by testing whether dma_handle is properly set. If dma_handle is properly returned, it means some DMA pages are allocated and dma_mmap_coherent should be used to map them. Otherwise, normal pages are allocated and pfn_remap_range should be called. This ensures that the correct mmap functions are used consistently, independently with logic details that determine which type of memory gets allocated. Fixes: a0e710a7def4 ("USB: usbfs: fix mmap dma mismatch") Cc: stable@vger.kernel.org Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn> Link: https://lore.kernel.org/r/20230515130958.32471-3-lrh2000@pku.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>