From: Sarah Sharp Date: Tue, 18 May 2010 23:05:21 +0000 (-0700) Subject: USB: xhci: Limit bus sg_tablesize to 62 TRBs. X-Git-Tag: v2.6.35-rc1~471^2~227 X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=bc88d2eba5e19d10dd546e428314909d889b3b6a;p=~emulex%2Finfiniband.git USB: xhci: Limit bus sg_tablesize to 62 TRBs. When a scatter-gather list is enqueued to the xHCI driver, it translates each entry into a transfer request block (TRB). Only 63 TRBs can be used per ring segment, and there must be one additional TRB reserved to make sure the hardware does not think the ring is empty (so the enqueue pointer doesn't equal the dequeue pointer). Limit the bus sg_tablesize to 62 TRBs. Signed-off-by: Sarah Sharp Cc: stable Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 417d37aff8d..98a73cd20cc 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -54,7 +54,7 @@ static int xhci_pci_setup(struct usb_hcd *hcd) struct pci_dev *pdev = to_pci_dev(hcd->self.controller); int retval; - hcd->self.sg_tablesize = TRBS_PER_SEGMENT - 1; + hcd->self.sg_tablesize = TRBS_PER_SEGMENT - 2; xhci->cap_regs = hcd->regs; xhci->op_regs = hcd->regs +