On 2019/2/1 17:13, Hanjun Guo wrote: > On 2019/2/1 13:55, Hanjun Guo wrote: >> Hi John, >> >> On 2019/1/31 17:54, John Garry wrote: >>> On 30/01/2019 07:01, Hanjun Guo wrote: >>>> From: Hanjun Guo <hanjun.guo@xxxxxxxxxx> >> [...] >>>> >>>> drivers/usb/core/hcd-pci.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c >>>> index 0343246..a9c33e6 100644 >>>> --- a/drivers/usb/core/hcd-pci.c >>>> +++ b/drivers/usb/core/hcd-pci.c >>>> @@ -188,6 +188,10 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) >>>> if (pci_enable_device(dev) < 0) >>>> return -ENODEV; >>>> >>>> + retval = dma_coerce_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32)); >>>> + if (retval) >>>> + return retval; >>> >>> Hi Hanjun, >>> >>> You're missing tidy-up upon failure. >> >> Good catch, needs to disable pci for failure, I will send >> a updated version to address the comments from you and Christoph. > > There is a _DMA method which was introduced in ACPI 6.2 to cover > this, I will try that solution then report back. We add a _DMA method under the hostbridge which the EHCI/OHCI being connected to, the calltrace is gone and EHCI works as expected. No need for kernel change, so this patch is dropped. Thanks Hanjun