| Subject | Re: [PATCH 08/13] xen/pvticketlock: disable interrupts while blocking | From | Peter Zijlstra <> | Date | Fri, 02 Sep 2011 16:47:06 +0200 |
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On Thu, 2011-09-01 at 17:55 -0700, Jeremy Fitzhardinge wrote: > From: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> > > We need to make sure interrupts are disabled while we're relying on the > contents of the per-cpu lock_waiting values, otherwise an interrupt > handler could come in, try to take some other lock, block, and overwrite > our values.
Would this make it illegal to take a spinlock from NMI context?
I know that its generally considered bad form, but there's at least one spinlock that's only taken from NMI context and thus hasn't got any deadlock potential.
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