Re: i386 IPI handlers running with hardirq_count == 0

[Andrew Morton]

On Thu, 29 Jun 2006 19:01:17 +1000
Keith Owens <kaos@xxxxxxxxxx> wrote:

> Macro arch/i386/kernel/entry.S::BUILD_INTERRUPT generates the code to
> handle an IPI and call the corresponding smp_<name> C code.
> BUILD_INTERRUPT does not update the hardirq_count for the interrupted
> task, that is left to the C code.  Some of the C IPI handlers do not
> call irq_enter(), so they are running in IRQ context but the
> hardirq_count field does not reflect this.  For example,
> smp_invalidate_interrupt does not set the hardirq count.
> 
> What is the best fix, change BUILD_INTERRUPT to adjust the hardirq
> count or audit all the C handlers to ensure that they call irq_enter()?
> 

The IPI handlers run with IRQs disabled.  Do we need a fix?

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