pagetables used in interrupt context

[弋天 卜]

Hi:

   I think it is for safe,people can open interrupt inside their own interrupt handler, so kernel must disable it before touch kernel data that must be protected.


在 2012-2-25，1:39，"subin gangadharan" <subingangadharan at gmail.com> 写道：

> Hi 卜弋天,
> 
>> 2.6.35, i checked the function handle_level_irq()and handle_edge_irq() in
>> chip.c, both of them will call handle_IRQ_event() which is in handle.c. and
>> the function handle_IRQ_event() will call the interrupt handler written by
>> user. Kernel does not open interrupt(ARM CPSR I bit)when calling interrupt
>> handler in handle_IRQ_event() function.
> 
> Thank you for the valuable pointers. I have looked at the
> handle_IRQ_event function, it seems at the end of the do while loop
> its unconditionally disable the local interrupt (ARM CPSR I bit). If
> the handler is running with interrupts disabled, why do we need to
> disable the interrupts again.
> 
> Could you please explain about this logic.
> 
> Thanks in advance for your help and sorry to take up your time on this.
> 
> 
> 
> -- 
> With Regards
> Subin Gangadharan
> 
> I am not afraid and I am also not afraid of being afraid.