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Date:   Wed, 3 Aug 2022 12:05:46 +0530
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Subject: Re: [PATCH v2 4/4] drivers: misc: Add Support for TMR Inject IP
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To:     Greg KH <gregkh@linuxfoundation.org>
CC:     Appana Durga Kedareswara rao 
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Hi Greg,

On 29/07/22 2:32 pm, Greg KH wrote:
> On Fri, Jul 29, 2022 at 01:43:47PM +0530, Rao, Appana Durga Kedareswara wrote:
>> Hi Greg,
>>
>> Thanks for the review.
>>
>> On 28/07/22 7:54 pm, Greg KH wrote:
>>> On Wed, Jul 20, 2022 at 11:30:16AM +0530, Appana Durga Kedareswara rao wrote:
>>>> From: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
>>>>
>>>> The Triple Modular Redundancy(TMR) provides functional fault injection by
>>>> changing selected MicroBlaze instructions, which provides the possibility
>>>> to verify that the TMR subsystem error detection and fault recovery logic
>>>> is working properly, provided sysfs entries which allow the user to inject
>>>> a fault.
>>>
>>> We already have a fault-injection api, why are you not using that?
>>>
>>
>> Inorder to inject the error using TMR inject IP, The API
>> which injects the error should be executed from Processor LMB,
>> below sysfs entry calls microblaze core API xmb_inject_err()
>> which switches the processor to real mode and injects the error,
>> Please find the code corresponds to xmb_inject_err() API here:
>> https://www.spinics.net/lists/arm-kernel/msg991888.html
> 
> You did not answer the question.  Why are you not using the in-kernel
> fault injection userspace api and why have you created your own?

will update the driver to use fault injection user space API in next 
version.

> 
> Also, please use lore.kernel.org links when possible.

Sure

Regards,
Kedar.
> 
> thanks,
> 
> greg k-h