How to handle the supervisor call in Xen on ARM?

How to handle the supervisor call in Xen on ARM?

[harry2845]

Now I've known that if I set the HCR.TGE, the supervisor call will be trapped
into hyp mode. But if I do nothing in hyp mode. After return to user, there
will be a kernel panic.

But I don't know how to handle the supervisor call, could someone give me
some advice? Thank you very much.



--
View this message in context: http://xen.1045712.n5.nabble.com/How-to-handle-the-supervisor-call-in-Xen-on-ARM-tp5724653.html
Sent from the Xen - Dev mailing list archive at Nabble.com.

Re: How to handle the supervisor call in Xen on ARM?

[Ian Campbell]

On Sun, 2014-09-07 at 19:42 -0700, harry2845 wrote:
> Now I've known that if I set the HCR.TGE, the supervisor call will be trapped
> into hyp mode. But if I do nothing in hyp mode. After return to user, there
> will be a kernel panic.

Yes, because you have to deal with all of the trapped general exceptions
somehow.

> But I don't know how to handle the supervisor call, could someone give me
> some advice?

I'm afraid not. You will need to spend some time reading the ARM ARM
manual and figure out what the correct response is to each thing which
is trapped by setting the HCR.TGE bit. Some might be handled by just
returning, others will require you to actually do something.

>  Thank you very much.

This is now the 3rd time you've started this thread. Please stick to a
single thread and reply there as necessary.

Ian.