usb: dwc2: Fix DMA cache alignment issues (4a4863bf) · Commits · 戴 / test

Insert a padding between data and the stored_xfer_buffer pointer to ensure they are not on the same cache line. Otherwise, the stored_xfer_buffer gets corrupted for IN URBs on non-cache-coherent systems. (In my case: Lantiq xRX200 MIPS) Fixes: ("usb: dwc2: host: Get aligned DMA in a more supported way") Fixes: ("usb: dwc2: Fix DMA alignment to start at allocated boundary") Cc: <stable@vger.kernel.org> Tested-by:

Douglas Anderson <dianders@chromium.org> Reviewed-by:

Douglas Anderson <dianders@chromium.org> Acked-by:

Minas Harutyunyan <hminas@synopsys.com> Signed-off-by:

Martin Schiller <ms@dev.tdt.de> Signed-off-by:

Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc2/hcd.c

+7 −3

Original line number	Diff line number	Diff line
		@@ -2480,8 +2480,10 @@ static void dwc2_free_dma_aligned_buffer(struct urb *urb)
		return;

		/* Restore urb->transfer_buffer from the end of the allocated area */
		memcpy(&stored_xfer_buffer, urb->transfer_buffer +
		urb->transfer_buffer_length, sizeof(urb->transfer_buffer));
		memcpy(&stored_xfer_buffer,
		PTR_ALIGN(urb->transfer_buffer + urb->transfer_buffer_length,
		dma_get_cache_alignment()),
		sizeof(urb->transfer_buffer));

		if (usb_urb_dir_in(urb)) {
		if (usb_pipeisoc(urb->pipe))
		@@ -2513,6 +2515,7 @@ static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
		* DMA
		*/
		kmalloc_size = urb->transfer_buffer_length +
		(dma_get_cache_alignment() - 1) +
		sizeof(urb->transfer_buffer);

		kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
		@@ -2523,7 +2526,8 @@ static int dwc2_alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
		* Position value of original urb->transfer_buffer pointer to the end
		* of allocation for later referencing
		*/
		memcpy(kmalloc_ptr + urb->transfer_buffer_length,
		memcpy(PTR_ALIGN(kmalloc_ptr + urb->transfer_buffer_length,
		dma_get_cache_alignment()),
		&urb->transfer_buffer, sizeof(urb->transfer_buffer));

		if (usb_urb_dir_out(urb))

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