Re: [PATCH v2 2/2] ARM: irqchip: mxs: add Alpascale ASM9260 support

From: Thomas Gleixner
Date: Mon Sep 21 2015 - 05:07:28 EST


On Sun, 20 Sep 2015, Marc Zyngier wrote:
> > Uff... in one of earliest reviews i was asked to add lock..
> > I also was asked to add asm9260 to some existing driver. Not sure if it
> > is still making sense.
>
> Adding or removing a lock is not about what people ask you to do. It is
> about requirements dictated by either the HW (you need to perform
> a given sequence atomically with respect to another code sequence), the
> kernel, or both. So I'd like to understand what is the underlying
> reason for this lock. It is not disabling interrupts, so it could end
> up being called in an interrupt context -> deadlock.

The callback is always called with interrupts disabled, so that's a
non issue. But still, the rationale for that lock is unclear.

Thanks,

tglx


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