Save someone else the debug cycles of figuring out why a driver's
transfer request is failing or causing undefined system behavior.
Buffers submitted for dma must come from GFP allocated / DMA-able
memory.
Return -EAGAIN matching the return value for dma_mapping_error() cases.
Cc: Alan Stern <st...@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sh...@linux.intel.com>
Cc: Mathias Nyman <mathias.ny...@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.willi...@intel.com>
---
drivers/usb/core/hcd.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 2518c3250750..ff7cd489f55d 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1502,6 +1502,9 @@ int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct
urb *urb,
ret = -EAGAIN;
else
urb->transfer_flags |= URB_DMA_MAP_PAGE;
+ } else if (is_vmalloc_addr(urb->transfer_buffer)) {
+ WARN_ONCE(1, "transfer buffer not dma
capable\n");
+ return -EAGAIN;
} else {
urb->transfer_dma = dma_map_single(
hcd->self.controller,
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
