2011.04.11. 20:53 keltezéssel, Alan Stern írta: > On Sun, 10 Apr 2011, Gabor Juhos wrote: > >> A Synopsys USB core used in various SoCs has a bug which might cause >> that the host controller not issuing ping. >> >> When software uses the Doorbell mechanism to remove queue heads, the >> host controller still has references to the removed queue head even >> after indicating an Interrupt on Async Advance. This happens if the last >> executed queue head's Next Link queue head is removed. >> >> Consequences of the defect: >> The Host controller fetches the removed queue head, using memory that >> would otherwise be deallocated.This results in incorrect transactions on >> both the USB and system memory. This may result in undefined behavior. > >> --- a/drivers/usb/host/ehci-q.c >> +++ b/drivers/usb/host/ehci-q.c >> @@ -1183,6 +1183,9 @@ static void end_unlink_async (struct ehci_hcd *ehci) >> ehci->reclaim = NULL; >> start_unlink_async (ehci, next); >> } >> + >> + if (ehci->has_synopsys_hc_bug) >> + writel((u32)ehci->async->qh_dma, &ehci->regs->async_next); >> } > > This should be ehci_writel(ehci, ...). You are right, I will change that. Thanks, Gabor
