In s390_pci_device_reset(), IOMMU mappings are torn down without first
resetting the device. For a PCI passthrough device this opens a window
where the device may issue DMA to addresses that no longer have valid IOMMU
mappings, causing an error (PEC 0x7) for the device on the host.
Fix this by calling pci_device_reset() before tearing down IOMMU mappings
in the default case. The dedicated ERROR-state case existed to issue
that same reset before falling through, so it can now be removed.
Fixes: 3e5cfba3ca0a ("s390x/pci: introduce S390PCIBusDevice qdev")
Cc: [email protected]
Signed-off-by: Farhan Ali <[email protected]>
---
hw/s390x/s390-pci-bus.c | 16 +---------------
1 file changed, 1 insertion(+), 15 deletions(-)
diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 2724b27ec2..7182d97a33 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -1786,22 +1786,8 @@ static void s390_pci_device_reset(DeviceState *dev)
return;
case ZPCI_FS_STANDBY:
break;
- case ZPCI_FS_ERROR:
- /*
- * Attempt a reset to recover the device. A device in ERROR state
- * can be transitioned to ENABLED or DISABLED state via guest
- * driven actions. Since this code path is also executed on
- * subsystem_reset() and the expected state of a configured device
- * after subsystem_reset() is to be in a DISABLED state, we need to
- * transition from ERROR to DISABLED.
- *
- * Linux guests drive the state transition from ERROR to DISABLED
- * via CLP_SET_DISABLE_PCI_FN. So it should be safe to transition
- * from ERROR to DISABLED state.
- */
- pci_device_reset(pbdev->pdev);
- /* fallthrough */
default:
+ pci_device_reset(pbdev->pdev);
pbdev->fh &= ~FH_MASK_ENABLE;
pbdev->state = ZPCI_FS_DISABLED;
break;
--
2.43.0
