Hi Thomas and Ingo, Could you have a look for this patch? It fix the wrong unmask action. Thanks.
> -----Original Message----- > From: Liu, Chuansheng > Sent: Thursday, November 15, 2012 12:53 AM > To: mi...@redhat.com; t...@linutronix.de > Cc: x...@kernel.org; linux-kernel@vger.kernel.org; Liu, Chuansheng > Subject: [PATCH] x86/irq,io_apic: Fix wrong unmask_ioapic calling when the irq > is masked > > > There is one typical case will cause this issue, that is: > One io-apic interrupt with ONE_SHOT and threaded, when interrupt is coming: > handle_fasteoi_irq() > --> mask_irq(desc) > ... > desc->irq_data.chip->irq_eoi(&desc->irq_data)[ack_apic_level] > --> ioapic_irqd_mask() > ... > ioapic_irqd_unmask() > > After that, the irq will be in unmasked state. > > It will break the ONE_SHOT and threaded irq, and brings some unwanted > issues. > Here adding the irqd_irq_masked() condition to know if unmasking action is > needed. > > Signed-off-by: liu chuansheng <chuansheng....@intel.com> > --- > arch/x86/kernel/apic/io_apic.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c > index 1817fa9..d963e76 100644 > --- a/arch/x86/kernel/apic/io_apic.c > +++ b/arch/x86/kernel/apic/io_apic.c > @@ -2479,7 +2479,8 @@ static inline void ioapic_irqd_unmask(struct irq_data > *data, > */ > if (!io_apic_level_ack_pending(cfg)) > irq_move_masked_irq(data); > - unmask_ioapic(cfg); > + if (!irqd_irq_masked(data)) > + unmask_ioapic(cfg); > } > } > #else > -- > 1.7.0.4 > >
