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Re: [Xen-devel] schedule() vs softirqs

On 15/12/06 17:27, "Hollis Blanchard" <hollisb@xxxxxxxxxx> wrote:

> We recently uncovered a bug on PowerPC where if a timer tick arrives
> just inside schedule() while interrupts are still enabled, the
> decrementer is never reprogrammed to that appropriate value. This is
> because once inside schedule(), we never handle any subsequent softirqs:
> we call context_switch() and resume the guest.

Easily fixed. You need to handle softirqs in the exit path to guest context.
You need to do this final check with interrupts disabled to avoid races.

 -- Keir

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