[PATCH] device-assignment: fix failure to exit on shared IRQ

[PATCH] device-assignment: fix failure to exit on shared IRQ

[Alex Williamson]

Since c1699988, piix config space isn't programmed until the first
system reset.  This means that when we call assign_irq() from
assigned_initfn(), we're going to get back an irq of 0x0, which
unfortunately matches our initialization value, so we don't bother
to call kvm_assign_irq().  Switch to a -1 initializer so we can
test whether kvm_assign_irq() is going to succeed and allow the
process to exit if it doesn't.  The guest irq will get reset to a
more appropriate value on system reset anyway.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---

 hw/device-assignment.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/hw/device-assignment.c b/hw/device-assignment.c
index b9cc06f..eb31c78 100644
--- a/hw/device-assignment.c
+++ b/hw/device-assignment.c
@@ -1346,7 +1346,7 @@ static int assigned_initfn(struct PCIDevice *pci_dev)
     e_intx = dev->dev.config[0x3d] - 1;
     dev->intpin = e_intx;
     dev->run = 0;
-    dev->girq = 0;
+    dev->girq = -1;
     dev->h_segnr = dev->host.seg;
     dev->h_busnr = dev->host.bus;
     dev->h_devfn = PCI_DEVFN(dev->host.dev, dev->host.func);

Re: [PATCH] device-assignment: fix failure to exit on shared IRQ

[Chris Wright]

* Alex Williamson (alex.williamson@redhat.com) wrote:
> Since c1699988, piix config space isn't programmed until the first
> system reset.  This means that when we call assign_irq() from
> assigned_initfn(), we're going to get back an irq of 0x0, which
> unfortunately matches our initialization value, so we don't bother
> to call kvm_assign_irq().  Switch to a -1 initializer so we can
> test whether kvm_assign_irq() is going to succeed and allow the
> process to exit if it doesn't.  The guest irq will get reset to a
> more appropriate value on system reset anyway.
> 
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Acked-by: Chris Wright <chrisw@redhat.com>

Re: [PATCH] device-assignment: fix failure to exit on shared IRQ

[Marcelo Tosatti]

On Wed, May 12, 2010 at 05:12:10AM -0400, Alex Williamson wrote:
> Since c1699988, piix config space isn't programmed until the first
> system reset.  This means that when we call assign_irq() from
> assigned_initfn(), we're going to get back an irq of 0x0, which
> unfortunately matches our initialization value, so we don't bother
> to call kvm_assign_irq().  Switch to a -1 initializer so we can
> test whether kvm_assign_irq() is going to succeed and allow the
> process to exit if it doesn't.  The guest irq will get reset to a
> more appropriate value on system reset anyway.
> 
> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Applied, thanks.