Re: [patch] MSI-X: fix resume crash

[Ingo Molnar <mingo@elte.hu>]

* Eric W. Biederman <ebiederm@xmission.com> wrote:

> > Eric's patch seems to have done the trick on my T60: i've done 10 
> > suspend+resumes and each worked fine. I've tidied up the description 
> > part of Eric's patch a bit for upstream application - find it below.
> 
> Thanks.  Tidying up the description has been on my todo list for the 
> last little bit but I just haven't gotten there.
> 
> I've gotten at least Tony's sign off on the architectural direction so 
> there is nothing to prevent this patch from going in.  Unless Linus or 
> someone wants a more thorough patch this late in the release cycle.
> 
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

i've updated the patch below with your sign-off, and trimmed the 
description to the relevant bits, for easy upstream application.

	Ingo

------------->
Subject: [patch] MSI-X: fix resume crash
From: Eric W. Biederman <ebiederm@xmission.com>

So I think the right solution is to simply make pci_enable_device just 
flip enable bits and move the rest of the work someplace else.

However a thorough cleanup is a little extreme for this point in the 
release cycle, so I think a quick hack that makes the code not stomp the 
irq when msi irq's are enabled should be the first fix.  Then we can 
later make the code not change the irqs at all.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 arch/cris/arch-v32/drivers/pci/bios.c |    4 +++-
 arch/frv/mb93090-mb00/pci-vdk.c       |    3 ++-
 arch/i386/pci/common.c                |    6 ++++--
 arch/ia64/pci/pci.c                   |    8 ++++++--
 4 files changed, 15 insertions(+), 6 deletions(-)

Index: linux/arch/cris/arch-v32/drivers/pci/bios.c
===================================================================
--- linux.orig/arch/cris/arch-v32/drivers/pci/bios.c
+++ linux/arch/cris/arch-v32/drivers/pci/bios.c
@@ -100,7 +100,9 @@ int pcibios_enable_device(struct pci_dev
 	if ((err = pcibios_enable_resources(dev, mask)) < 0)
 		return err;
 
-	return pcibios_enable_irq(dev);
+	if (!dev->msi_enabled)
+		pcibios_enable_irq(dev);
+	return 0;
 }
 
 int pcibios_assign_resources(void)
Index: linux/arch/frv/mb93090-mb00/pci-vdk.c
===================================================================
--- linux.orig/arch/frv/mb93090-mb00/pci-vdk.c
+++ linux/arch/frv/mb93090-mb00/pci-vdk.c
@@ -466,6 +466,7 @@ int pcibios_enable_device(struct pci_dev
 
 	if ((err = pcibios_enable_resources(dev, mask)) < 0)
 		return err;
-	pcibios_enable_irq(dev);
+	if (!dev->msi_enabled)
+		pcibios_enable_irq(dev);
 	return 0;
 }
Index: linux/arch/i386/pci/common.c
===================================================================
--- linux.orig/arch/i386/pci/common.c
+++ linux/arch/i386/pci/common.c
@@ -434,11 +434,13 @@ int pcibios_enable_device(struct pci_dev
 	if ((err = pcibios_enable_resources(dev, mask)) < 0)
 		return err;
 
-	return pcibios_enable_irq(dev);
+	if (!dev->msi_enabled)
+		return pcibios_enable_irq(dev);
+	return 0;
 }
 
 void pcibios_disable_device (struct pci_dev *dev)
 {
-	if (pcibios_disable_irq)
+	if (!dev->msi_enabled && pcibios_disable_irq)
 		pcibios_disable_irq(dev);
 }
Index: linux/arch/ia64/pci/pci.c
===================================================================
--- linux.orig/arch/ia64/pci/pci.c
+++ linux/arch/ia64/pci/pci.c
@@ -557,14 +557,18 @@ pcibios_enable_device (struct pci_dev *d
 	if (ret < 0)
 		return ret;
 
-	return acpi_pci_irq_enable(dev);
+	if (!dev->msi_enabled)
+		return acpi_pci_irq_enable(dev);
+	return 0;
 }
 
 void
 pcibios_disable_device (struct pci_dev *dev)
 {
 	BUG_ON(atomic_read(&dev->enable_cnt));
-	acpi_pci_irq_disable(dev);
+	if (!dev->msi_enabled)
+		acpi_pci_irq_disable(dev);
+	return 0;
 }
 
 void