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Re: [Xen-devel] SMMU, Unhandled context fault

Hi Julien,

On Fri, May 06, 2016 at 01:48:54PM +0100, Julien Grall wrote:
>Hello Peng,
>On 03/05/16 14:58, Peng Fan wrote:
>>On Tue, May 03, 2016 at 11:58:17AM +0100, Julien Grall wrote:
>>>On 29/04/16 15:28, Peng Fan wrote:
>>>>Hi Julien,
>>>Hello Peng,
>>>>On Thu, Apr 28, 2016 at 02:14:58PM +0100, Julien Grall wrote:
>>>>>>Is there any big difference between XEN SMMU driver and linux SMMU driver?
>>>>>>I know that XEN only support Stage 2. But the initliaization flow is 
>>>>>>almost the same.
>>>>>The SMMU driver for Xen is a port from Linux 3.19-rc0. Since then the Linux
>>>>>driver has been reworked and it might be possible that we have missed some
>>>>>bug fix.
>>>>>Aside that, for Xen, the page tables are always shared between the SMMU and
>>>>>the processor.
>>>>Thanks. I shared two picture that dumped using TRACE32.
>>>>Would you please help check?
>>>I am sorry but I have got no idea what each columns are supposed to contain.
>>>Can you share more details?
>>I add one more picture.
>>The first colum is guest physical address, the second is machine address.
>Let's take a step back. Does the MMC is working when used in DOM0?
>>The FSR 0x40000410, EF is 1, TF is 0. This means the mapping is correct, but 
>>is an external fault during translation?
>>The PTWF shows An external fault occurred while processing a translation 
>>table walk
>>I may need to check what kind external fault, it maybe not a mapping error.
>Edgar mentioned that NSATTR is 0, which means that the input transation as a
>secure attribute. Have you dig into it?

I think we are close to find the root cause, we have a specific hw module
to check the memory transactions. After configure the module to disable
memory access check, I do not met SMMU context fault. I am checking the
configuration for the hw module.

This is not about NSATTR.

>Julien Grall

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