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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-05-10 20:12:38 +0400 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-05-12 03:40:41 +0400 |
| commit | 7c0482e3d055e5de056d3c693b821e39205b99ae (patch) | |
| tree | ad8d3ff6965d675c6bd255c5665deab7fba5df9f /arch/powerpc/kernel/irq.c | |
| parent | 4e25651b70b8d6ded7229ead8181619e121b648d (diff) | |
| download | linux-7c0482e3d055e5de056d3c693b821e39205b99ae.tar.xz | |
powerpc/irq: Fix another case of lazy IRQ state getting out of sync
So we have another case of paca->irq_happened getting out of
sync with the HW irq state. This can happen when a perfmon
interrupt occurs while soft disabled, as it will return to a
soft disabled but hard enabled context while leaving a stale
PACA_IRQ_HARD_DIS flag set.
This patch fixes it, and also adds a test for the condition
of those flags being out of sync in arch_local_irq_restore()
when CONFIG_TRACE_IRQFLAGS is enabled.
This helps catching those gremlins faster (and so far I
can't seem see any anymore, so that's good news).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/irq.c')
| -rw-r--r-- | arch/powerpc/kernel/irq.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index c6c6f3b7f8cd..641da9e868ce 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -229,6 +229,19 @@ notrace void arch_local_irq_restore(unsigned long en) */ if (unlikely(irq_happened != PACA_IRQ_HARD_DIS)) __hard_irq_disable(); +#ifdef CONFIG_TRACE_IRQFLAG + else { + /* + * We should already be hard disabled here. We had bugs + * where that wasn't the case so let's dbl check it and + * warn if we are wrong. Only do that when IRQ tracing + * is enabled as mfmsr() can be costly. + */ + if (WARN_ON(mfmsr() & MSR_EE)) + __hard_irq_disable(); + } +#endif /* CONFIG_TRACE_IRQFLAG */ + set_soft_enabled(0); /* |