Commit 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and
pcibios_free_irq()") changed IRQ handling on PCI driver probing.
It inadvertently broke resume from system sleep on AMD platforms:
https://lore.kernel.org/r/20150926164651.GA3640@xxxxxxx/
This was fixed by two independent commits:
* 8affb487d4a4 ("x86/PCI: Don't alloc pcibios-irq when MSI is enabled")
* cbbc00be2ce3 ("iommu/amd: Prevent binding other PCI drivers to IOMMU
PCI devices")
The breaking change and one of these two fixes were subsequently reverted:
* fe25d078874f ("Revert "x86/PCI: Don't alloc pcibios-irq when MSI is
enabled"")
* 6c777e8799a9 ("Revert "PCI, x86: Implement pcibios_alloc_irq() and
pcibios_free_irq()"")
This rendered the second fix unnecessary, so revert it as well. It used
the match_driver flag in struct pci_dev, which is internal to the PCI core
and not supposed to be touched by arbitrary drivers.
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
---
I would have cc'ed Jiang Liu (author of the commit reverted here)
but his Intel e-mail address appears to no longer be working.
Someone with the same name has recently started to contribute
using an Alibaba e-mail address, but I'm not sure it's the same
person.
drivers/iommu/amd/init.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index dd9e26b..33b6e12 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -2030,9 +2030,6 @@ static int __init iommu_init_pci(struct amd_iommu *iommu)
if (!iommu->dev)
return -ENODEV;
- /* Prevent binding other PCI device drivers to IOMMU devices */
- iommu->dev->match_driver = false;
-
/* ACPI _PRT won't have an IRQ for IOMMU */
iommu->dev->irq_managed = 1;
--
2.47.2
