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Subject: Semantics of lv1_pause()
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Geoff Levand <geoff@infradead.org>
Date: Tue, 10 Jul 2012 13:20:02 +1000
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Hi Geoff !

Do you have access to any kind of documentation regarding the precise
semantics of lv1_pause() ?

I'm fixing various issues with our idle loops, among other things,
because we are soft-disabled when we hit ppc_md.powersave() but not
hard-disabled, there could be an interrupt marked as pending and not
taken yet.

Will that work properly ? I have this understanding that it might
not ... but heh.

Also if I call lv1_pause() with MSR_EE off, will it work ? Will it
return with MSR_EE on like H_CEDE does on pseries ?

Cheers,
Ben.