| Message ID | 20190218063730.26870-1-ms@dev.tdt.de (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 4a4863bf2e7932e584a3a462d3c6daf891142ddc |
| Headers | show |
| Series | usb: dwc2: Fix DMA cache alignment issues | expand |
Hi, On Sun, Feb 17, 2019 at 10:37 PM Martin Schiller <ms@dev.tdt.de> wrote: > > 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: 3bc04e28a030 ("usb: dwc2: host: Get aligned DMA in a more supported way") > Fixes: 56406e017a88 ("usb: dwc2: Fix DMA alignment to start at allocated boundary") > Signed-off-by: Martin Schiller <ms@dev.tdt.de> > --- > drivers/usb/dwc2/hcd.c | 10 +++++++--- > 1 file changed, 7 insertions(+), 3 deletions(-) This patch has been in the back of my mind for a while bug I never got around to it. Today I was debugging memory corruption problems when using a webcam on dwc2 on rk3288-veyron-jerry. This patch appears to solve my problems nicely. Thanks! Tested-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Cc: <stable@vger.kernel.org>
On 5/29/2019 10:31 PM, Doug Anderson wrote: > Hi, > > On Sun, Feb 17, 2019 at 10:37 PM Martin Schiller <ms@dev.tdt.de> wrote: >> >> 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: 3bc04e28a030 ("usb: dwc2: host: Get aligned DMA in a more supported way") >> Fixes: 56406e017a88 ("usb: dwc2: Fix DMA alignment to start at allocated boundary") >> Signed-off-by: Martin Schiller <ms@dev.tdt.de> >> --- >> drivers/usb/dwc2/hcd.c | 10 +++++++--- >> 1 file changed, 7 insertions(+), 3 deletions(-) > > This patch has been in the back of my mind for a while bug I never got > around to it. Today I was debugging memory corruption problems when > using a webcam on dwc2 on rk3288-veyron-jerry. This patch appears to > solve my problems nicely. Thanks! > > Tested-by: Douglas Anderson <dianders@chromium.org> > Reviewed-by: Douglas Anderson <dianders@chromium.org> > Cc: <stable@vger.kernel.org> > Acked-by: Minas Harutyunyan <hminas@synopsys.com>
diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index dd82fa516f3f..f3035dd4db25 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -2664,8 +2664,10 @@ 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)) @@ -2697,6 +2699,7 @@ 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); @@ -2707,7 +2710,8 @@ 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))
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: 3bc04e28a030 ("usb: dwc2: host: Get aligned DMA in a more supported way") Fixes: 56406e017a88 ("usb: dwc2: Fix DMA alignment to start at allocated boundary") Signed-off-by: Martin Schiller <ms@dev.tdt.de> --- drivers/usb/dwc2/hcd.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)