Re: [PATCH v2 2/2] ppc/spapr: Disable VFIO BAR mmap during EEH PE reset

[Narayana Murty N]

Hi Cédric,

On 27/10/26 9:38 PM, Cédric Le Goater wrote:

index 428ab2f069..931df22add 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c

@@ -1949,6 +1949,38 @@ static void vfio_mmap_set_enabled(VFIOPCIDevice *vdev, bool enabled)

      }
  }
+/*
+ * Prevent a pending INTx mmap timer from restoring BAR mmap while
+ * the PE is undergoing EEH reset.  Keep BAR accesses on the VFIO
+ * region read/write path until PE configuration completes.
+ */
+void vfio_pci_eeh_pre_reset(PCIDevice *pdev)
+{
+    VFIOPCIDevice *vdev = VFIO_PCI_DEVICE(pdev);
+
+    if (vdev->intx.mmap_timer) {
+        timer_del(vdev->intx.mmap_timer);
+    }
+
+    vfio_mmap_set_enabled(vdev, false);
+}
+
+void vfio_pci_eeh_post_configure(PCIDevice *pdev)
+{
+    VFIOPCIDevice *vdev = VFIO_PCI_DEVICE(pdev);
+
+    if (vdev->interrupt == VFIO_INT_INTx && vdev->intx.pending) {
+        if (vdev->intx.mmap_timer && vdev->intx.mmap_timeout) {
+            timer_mod(vdev->intx.mmap_timer,
+                      qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) +
+                      vdev->intx.mmap_timeout);
+        }
+        return;
+    }
+
+    vfio_mmap_set_enabled(vdev, true);
+}
+
  static void vfio_bar_prepare(VFIOPCIDevice *vdev, int nr)
  {
      VFIOBAR *bar = &vdev->bars[nr];
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index c9ab949870..63fa378fbc 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -266,6 +266,8 @@ struct vfio_pci_hot_reset_info;
  void vfio_pci_pre_reset(VFIOPCIDevice *vdev);
  void vfio_pci_post_reset(VFIOPCIDevice *vdev);
+void vfio_pci_eeh_pre_reset(PCIDevice *pdev);
+void vfio_pci_eeh_post_configure(PCIDevice *pdev);
  bool vfio_pci_host_match(PCIHostDeviceAddress *addr, const char *name);
  int vfio_pci_get_pci_hot_reset_info(VFIOPCIDevice *vdev,

                                      struct vfio_pci_hot_reset_info **info_p);

These are POWER-only routines. Why put them under hw/vfio/pci.c ?

Yes, agreed.

These helpers are specific to the sPAPR EEH recovery sequence, so putting
vfio_pci_eeh_pre_reset() and vfio_pci_eeh_post_configure() in generic
VFIO PCI code is not the right layering.

I'll move the EEH-specific pre-reset/post-configure handling back into
hw/ppc/spapr_pci_vfio.c and remove the corresponding declarations from
hw/vfio/pci.h.

Thanks,
Narayana Murty.>

C.