[ECOS] nested interrupt question

[Eric de Jong]

Hello BRS/johnsonest,

>      here, switch to svc mode,so enable interrupt, if interrupt occur at
>this time, r0-r5 stored in _exception_stack was corrupted,new r0-r5 will be
>pushed into _exception_stack.so last interupt failed to restore.right?
>     my key question is that:
> 1) when interrupt can come again after cpsr updated? Is it immediately?

no, interrupt can not come again because the interrupt disable bit in cpsr is
not modified (and is set after handling an interrupt)

Further in the code the exeption stack is copied to the system stack, and thus
interrupts may get enabled again.

Eric.


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