[PATCH] x86, irq: Keep IRQ assignment for PCI devices during suspend/hibernation

From: Jiang Liu
Date: Wed Jul 30 2014 - 05:34:44 EST


Function pci_disable_device() may be called for PCI devices during
suspend/hibernation, which in turn may release IRQ assigned to PCI
interrupt. Later when pci_enable_device() is called during resume,
a different IRQ may be assigned and thus break the driver.
So keep IRQ assignment for PCI devices during suspend/hibernation.
We check pci_dev.dev.power.is_prepared to detect that pci_disable_device()
and pci_enable_device() is called during suspend/hibernation.

Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
Hi Borislav,
I can't reproduce the issue with my test machine. So could you
please help to test this patch?
Regards!
Gerry
---
arch/x86/pci/common.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 059a76c29739..417de4c92e8f 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -662,14 +662,15 @@ int pcibios_enable_device(struct pci_dev *dev, int mask)
if ((err = pci_enable_resources(dev, mask)) < 0)
return err;

- if (!pci_dev_msi_enabled(dev))
+ if (!pci_dev_msi_enabled(dev) && !dev->dev.pm.is_prepared)
return pcibios_enable_irq(dev);
return 0;
}

void pcibios_disable_device (struct pci_dev *dev)
{
- if (!pci_dev_msi_enabled(dev) && pcibios_disable_irq)
+ if (!pci_dev_msi_enabled(dev) && pcibios_disable_irq &&
+ !dev->dev.pm.is_prepared)
pcibios_disable_irq(dev);
}

--
1.7.10.4

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