[PATCH] ARM: avoid Cortex-A9 livelock on tight dmb loops

[Russell King - ARM Linux]

On Sun, Apr 15, 2018 at 03:08:34PM +0100, Russell King - ARM Linux wrote:
> On Wed, Apr 11, 2018 at 07:11:39AM -0700, Tony Lindgren wrote:
> > We already have code in the kernel (and in the bootrom) to "park" a
> > cpu after starting. But using it without resetting the cpu would require
> > 1-1 memory mapping or modifying the code. That is if we wanted to use
> > the same code also for parking the cpus for kexec without resetting
> > them.
> 
> In which case, how about using:
> 
> 	while (1) {
> 		cpu_relax();
> 		wfe();
> 	}
> 
> instead - that appears to also have the desired effect, allowing kdump
> to work on the SDP4430.

... but results in compile failures on non-ARMv7 targets.

-- 
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