diff options
Diffstat (limited to 'Revert-xhci-1.0-Limit-arbitrarily-aligned-scatter-gather.patch')
| -rw-r--r-- | Revert-xhci-1.0-Limit-arbitrarily-aligned-scatter-gather.patch | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/Revert-xhci-1.0-Limit-arbitrarily-aligned-scatter-gather.patch b/Revert-xhci-1.0-Limit-arbitrarily-aligned-scatter-gather.patch new file mode 100644 index 000000000..a1920dd6f --- /dev/null +++ b/Revert-xhci-1.0-Limit-arbitrarily-aligned-scatter-gather.patch @@ -0,0 +1,86 @@ +From 7efb6dbd0d825899955fd4035504823bb5c1124c Mon Sep 17 00:00:00 2001 +From: Sarah Sharp <sarah.a.sharp@linux.intel.com> +Date: Tue, 04 Mar 2014 22:28:16 +0000 +Subject: Revert "xhci 1.0: Limit arbitrarily-aligned scatter gather." + +This reverts commit 247bf557273dd775505fb9240d2d152f4f20d304, since it +causes USB 3.0 mass storage devices to fail on xHCI 1.0 hosts. + +The block layer may submit scatter-gather lists with entries that +are multiples of 512-byte blocks. That's fine for USB 2.0 devices, +where the bulk endpoint max packet size is 512 bytes. But USB 3.0 +devices have bulk endpoints with a 1024 byte max packet size. + +That means when the block layer submits a scatter-gather list with one +entry that includes, say, three 512-byte blocks, this code will reject +the URB if it's submitted to a USB 3.0 bulk endpoint: + +int usb_submit_urb(struct urb *urb, gfp_t mem_flags) +{ +... + max = usb_endpoint_maxp(&ep->desc); +... + } else if (urb->num_sgs && !urb->dev->bus->no_sg_constraint && + dev->speed != USB_SPEED_WIRELESS) { + struct scatterlist *sg; + int i; + + for_each_sg(urb->sg, sg, urb->num_sgs - 1, i) + if (sg->length % max) + return -EINVAL; + } + +This results in failures with USB 3.0 drives. For me, a failure to +auto-mount the device. For others, a read or write SCSI command +failure. + +This commit was put in place so that we could get scatter-gather support +for the ASIX USB ethernet adapter on non-1.0 hosts. It was a quick fix +until we implemented TD fragments properly in the driver. Since it +breaks USB 3.0 mass storage, we need to revert it, and revert +scatter-gather support for the ASIX devices. + +Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> +Cc: stable@vger.kernel.org # 3.12 +--- +diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c +index 652be21..8fe4e12 100644 +--- a/drivers/usb/host/xhci.c ++++ b/drivers/usb/host/xhci.c +@@ -4762,6 +4762,9 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) + /* Accept arbitrarily long scatter-gather lists */ + hcd->self.sg_tablesize = ~0; + ++ /* support to build packet from discontinuous buffers */ ++ hcd->self.no_sg_constraint = 1; ++ + /* XHCI controllers don't stop the ep queue on short packets :| */ + hcd->self.no_stop_on_short = 1; + +@@ -4786,14 +4789,6 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) + /* xHCI private pointer was set in xhci_pci_probe for the second + * registered roothub. + */ +- xhci = hcd_to_xhci(hcd); +- /* +- * Support arbitrarily aligned sg-list entries on hosts without +- * TD fragment rules (which are currently unsupported). +- */ +- if (xhci->hci_version < 0x100) +- hcd->self.no_sg_constraint = 1; +- + return 0; + } + +@@ -4822,9 +4817,6 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) + if (xhci->hci_version > 0x96) + xhci->quirks |= XHCI_SPURIOUS_SUCCESS; + +- if (xhci->hci_version < 0x100) +- hcd->self.no_sg_constraint = 1; +- + /* Make sure the HC is halted. */ + retval = xhci_halt(xhci); + if (retval) +-- +cgit v0.9.2 |