OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

xhci: Fix immediate data transfer if buffer is already DMA mapped 

xhci immediate data transfer (IDT) support in 5.2-rc1 caused regression
on various Samsung Exynos boards with ASIX USB 2.0 ethernet dongle.

If the transfer buffer in the URB is already DMA mapped then IDT should
not be used. urb->transfer_dma will already contain a valid dma address,
and there is no guarantee the data in urb->transfer_buffer is valid.

The IDT support patch used urb->transfer_dma as a temporary storage,
copying data from urb->transfer_buffer into it.

Issue was solved by preventing IDT if transfer buffer is already dma
mapped, and by not using urb->transfer_dma as temporary storage.

Fixes: 33e39350eb ("usb: xhci: add Immediate Data Transfer support")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
CC: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mathias Nyman 2019-05-22 14:34:00 +03:00 committed by Greg Kroah-Hartman
parent 7aa1bb2ffd
commit 13b82b7463
2 changed files with 8 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
drivers/usb/host/xhci-ring.c
View File

@ -3432,11 +3432,14 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
if (urb->transfer_buffer_length > 0) {
u32 length_field, remainder;
u64 addr;
if (xhci_urb_suitable_for_idt(urb)) {
memcpy(&urb->transfer_dma, urb->transfer_buffer,
memcpy(&addr, urb->transfer_buffer,
urb->transfer_buffer_length);
field |= TRB_IDT;
} else {
addr = (u64) urb->transfer_dma;
}
remainder = xhci_td_remainder(xhci, 0,
@ -3449,8 +3452,8 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
if (setup->bRequestType & USB_DIR_IN)
field |= TRB_DIR_IN;
queue_trb(xhci, ep_ring, true,
lower_32_bits(urb->transfer_dma),
upper_32_bits(urb->transfer_dma),
lower_32_bits(addr),
upper_32_bits(addr),
length_field,
field | ep_ring->cycle_state);
}

3
drivers/usb/host/xhci.h
View File

@ -2160,7 +2160,8 @@ static inline bool xhci_urb_suitable_for_idt(struct urb *urb)
{
if (!usb_endpoint_xfer_isoc(&urb->ep->desc) && usb_urb_dir_out(urb) &&
usb_endpoint_maxp(&urb->ep->desc) >= TRB_IDT_MAX_SIZE &&
urb->transfer_buffer_length <= TRB_IDT_MAX_SIZE)
urb->transfer_buffer_length <= TRB_IDT_MAX_SIZE &&
!(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP))
return true;
return false;