[PATCH v2 2/2] arm64: enable context tracking
Larry Bassel
larry.bassel at linaro.org
Wed May 7 14:35:51 PDT 2014
On 07 May 14 11:17, Will Deacon wrote:
> On Wed, May 07, 2014 at 12:32:29AM +0100, Larry Bassel wrote:
> > Make calls to ct_user_enter when the kernel is exited
> > and ct_user_exit when the kernel is entered (in el0_da,
> > el0_ia, el0_svc, el0_irq).
>
> Why only these entry points? I can reschedule after any exception from EL0,
> so I'd expect all exceptions from userspace to need annotating, no?
>
> > These macros expand to function calls which will only work
> > properly if el0_sync and related code has been rearranged
> > (in a previous patch of this series).
> >
> > In order to avoid saving registers, the slow syscall path
> > is forced (as x86 does).
>
> ... and if you decide to handle undef exceptions, I think you'll need
> the register saving too, in case the kernel needs to perform emulation.
These are excellent points, I will rework the patch and submit v3.
Thanks for the feedback.
>
> Will
Larry
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