Re: [PATCH v3 1/8] arm64: Do not enable IRQs for ct_user_exit

From: James Morse
Date: Fri Jun 07 2019 - 05:38:09 EST


Hi Julien,

On 06/06/2019 10:31, Julien Thierry wrote:
> For el0_dbg and el0_error, DAIF bits get explicitly cleared before
> calling ct_user_exit.
>
> When context tracking is disabled, DAIF gets set (almost) immediately
> after. When context tracking is enabled, among the first things done
> is disabling IRQs.
>
> What is actually needed is:
> - PSR.D = 0 so the system can be debugged (should be already the case)
> - PSR.A = 0 so async error can be handled during context tracking
>
> Do not clear PSR.I in those two locations.

(last time I looked at this I wrongly assumed ct_user_exit() should be run with interrupts
masked, but that isn't what you're saying).

Reviewed-by: James Morse <james.morse@xxxxxxx>


Thanks,

James