Revert "PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()"

991de2e590 ("PCI, x86: Implement pcibios_alloc_irq() and
pcibios_free_irq()") appeared in v4.3 and helps support IOAPIC hotplug.

Олег reported that the Elcus-1553 TA1-PCI driver worked in v4.2 but not
v4.3 and bisected it to 991de2e590.  Sunjin reported that the RocketRAID
272x driver worked in v4.2 but not v4.3.  In both cases booting with
"pci=routirq" is a workaround.

I think the problem is that after 991de2e590, we no longer call
pcibios_enable_irq() for upstream bridges.  Prior to 991de2e590, when a
driver called pci_enable_device(), we recursively called
pcibios_enable_irq() for upstream bridges via pci_enable_bridge().

After 991de2e590, we call pcibios_enable_irq() from pci_device_probe()
instead of the pci_enable_device() path, which does *not* call
pcibios_enable_irq() for upstream bridges.

Revert 991de2e590 to fix these driver regressions.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211
Fixes: 991de2e590 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()")
Reported-and-tested-by: Олег Мороз <oleg.moroz@mcc.vniiem.ru>
Reported-by: Sunjin Yang <fan4326@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
CC: Jiang Liu <jiang.liu@linux.intel.com>
This commit is contained in:
Bjorn Helgaas
2016-02-17 12:26:42 -06:00
parent 67b4eab91c
commit 6c777e8799
5 changed files with 40 additions and 19 deletions

View File

@@ -256,13 +256,10 @@ static int intel_mid_pci_irq_enable(struct pci_dev *dev)
static void intel_mid_pci_irq_disable(struct pci_dev *dev)
{
if (dev->irq_managed && dev->irq > 0) {
if (!mp_should_keep_irq(&dev->dev) && dev->irq_managed &&
dev->irq > 0) {
mp_unmap_irq(dev->irq);
dev->irq_managed = 0;
/*
* Don't reset dev->irq here, otherwise
* intel_mid_pci_irq_enable() will fail on next call.
*/
}
}