Commit 22b6839b authored Aug 24, 2015 by Guilherme G. Piccoli Committed by Michael Ellerman Aug 26, 2015

PCI: Make pci_msi_setup_pci_dev() non-static for use by arch code



Commit 1851617c ("PCI/MSI: Disable MSI at enumeration even if kernel
doesn't support MSI") changed the location of the code that initialises
dev->msi_cap/msix_cap and then disables MSI/MSI-X interrupts at PCI
probe time in devices that have this flag set. It moved the code from
pci_msi_init_pci_dev() to a new function named pci_msi_setup_pci_dev(),
called by pci_setup_device().

The pseries PCI probing code does not call pci_setup_device(), so since
the aforementioned commit the function pci_msi_setup_pci_dev() is not
called and MSI/MSI-X interrupts are left enabled. Additionally because
dev->msi_cap/msix_cap are not initialised no driver can ever enable
MSI/MSI-X.

To fix this, the pseries PCI probe should manually call
pci_msi_setup_pci_dev(), so this patch makes it non-static.

Fixes: 1851617c ("PCI/MSI: Disable MSI at enumeration even if kernel doesn't support MSI")
[mpe: Update change log to mention dev->msi_cap/msix_cap]
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent c13dcf9f

drivers/pci/probe.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1108,7 +1108,7 @@ int pci_cfg_space_size(struct pci_dev *dev)

		#define LEGACY_IO_RESOURCE (IORESOURCE_IO \| IORESOURCE_PCI_FIXED)

		static void pci_msi_setup_pci_dev(struct pci_dev *dev)
		void pci_msi_setup_pci_dev(struct pci_dev *dev)
		{
		/*
		* Disable the MSI hardware to avoid screaming interrupts

include/linux/pci.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -1202,6 +1202,7 @@ struct msix_entry {
		u16 entry; /* driver uses to specify entry, OS writes */
		};

		void pci_msi_setup_pci_dev(struct pci_dev *dev);

		#ifdef CONFIG_PCI_MSI
		int pci_msi_vec_count(struct pci_dev *dev);

Admin message