Re: [RESEND] serial: 8250_bcm7271: move spin_lock_irqsave to spin_lock in interrupt handler

From: tuo cao
Date: Sat Aug 27 2022 - 05:42:35 EST


No, whether it's spin_lock_irqsave() or spin_lock(), the security is
the same. Since this commit:e58aa3d2d0cc01ad8d6f7f640a0670433f794922,
interrupt nesting is disabled, which means interrupts has disabled in
the interrupt handlers. So, it is unnecessary to call
spin_lock_irqsave in a interrupt handler. And it takes less time
obviously to use spin_lock(),so I think this change is needed.

Finally, I'm sorry I lacked real hardware to verify it and can't
provide changelog text.

Thanks.

Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> 于2022年8月22日周一 22:25写道:
>
> On Mon, Aug 22, 2022 at 10:11:10PM +0800, Tuo Cao wrote:
> > it is unnecessary to call spin_lock_irqsave in a interrupt handler.
>
> Yes, but it is safer to do so, right?
>
> Why is this change needed?
>
> Did you test it on real hardware to verify it works?
>
> We need a lot more information in the changelog text before being able
> to accept this.
>
> thanks,
>
> greg k-h