[PATCH 5.4 39/83] s390/pci: do not set affinity for floating irqs

From: Greg Kroah-Hartman
Date: Fri May 01 2020 - 09:39:06 EST


From: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>

commit 86dbf32da150339ca81509fa2eb84c814b55258b upstream.

with the introduction of CPU directed interrupts the kernel
parameter pci=force_floating was introduced to fall back
to the previous behavior using floating irqs.

However we were still setting the affinity in that case,
both in __irq_alloc_descs() and via the irq_set_affinity
callback in struct irq_chip.

For the former only set the affinity in the directed case.

The latter is explicitly set in zpci_directed_irq_init()
so we can just leave it unset for the floating case.

Fixes: e979ce7bced2 ("s390/pci: provide support for CPU directed interrupts")
Co-developed-by: Alexander Schmidt <alexs@xxxxxxxxxxxxx>
Signed-off-by: Alexander Schmidt <alexs@xxxxxxxxxxxxx>
Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/s390/pci/pci_irq.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

--- a/arch/s390/pci/pci_irq.c
+++ b/arch/s390/pci/pci_irq.c
@@ -115,7 +115,6 @@ static struct irq_chip zpci_irq_chip = {
.name = "PCI-MSI",
.irq_unmask = pci_msi_unmask_irq,
.irq_mask = pci_msi_mask_irq,
- .irq_set_affinity = zpci_set_irq_affinity,
};

static void zpci_handle_cpu_local_irq(bool rescan)
@@ -276,7 +275,9 @@ int arch_setup_msi_irqs(struct pci_dev *
rc = -EIO;
if (hwirq - bit >= msi_vecs)
break;
- irq = __irq_alloc_descs(-1, 0, 1, 0, THIS_MODULE, msi->affinity);
+ irq = __irq_alloc_descs(-1, 0, 1, 0, THIS_MODULE,
+ (irq_delivery == DIRECTED) ?
+ msi->affinity : NULL);
if (irq < 0)
return -ENOMEM;
rc = irq_set_msi_desc(irq, msi);