Trying to be too clever with setting the irq_disabled flag. PCI 2.3
disabled devices can still share IRQs, which can lead to clearing
the irq_disabled flag, preventing the EOI from registering, and leaving
the device without interrupts. Interrupt handler should only ever
set irq_disabled and we can exit earlier to avoid the config space
access if we know we're disabled.
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
---
drivers/vfio/vfio_intrs.c | 9 ++++++++-
1 files changed, 8 insertions(+), 1 deletions(-)
diff --git a/drivers/vfio/vfio_intrs.c b/drivers/vfio/vfio_intrs.c
index 604082c..73e3deb 100644
--- a/drivers/vfio/vfio_intrs.c
+++ b/drivers/vfio/vfio_intrs.c
@@ -57,6 +57,12 @@ irqreturn_t vfio_interrupt(int irq, void *dev_id)
spin_lock_irq(&vdev->irqlock);
+ /* INTX disabled interrupts can still be shared */
+ if (vdev->irq_disabled) {
+ spin_unlock_irq(&vdev->irqlock);
+ return ret;
+ }
+
if (vdev->pci_2_3) {
pci_block_user_cfg_access(pdev);
@@ -87,7 +93,8 @@ done:
ret = IRQ_HANDLED;
}
- vdev->irq_disabled = (ret == IRQ_HANDLED);
+ if (ret == IRQ_HANDLED)
+ vdev->irq_disabled = true;
spin_unlock_irq(&vdev->irqlock);
--
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