From b20d26b6c37d20486ee30000155e01fdabc445a1 Mon Sep 17 00:00:00 2001
From: Laurent Vivier <lvivier@redhat.com>
Date: Mon, 6 Jul 2015 13:05:56 +0200
Subject: [PATCH 30/31] sPAPR: Clear stale MSIx table during EEH reset
Message-id: <1436187956-15948-4-git-send-email-lvivier@redhat.com>
Patchwork-id: 66741
O-Subject: [RHEL7.2 qemu-kvm-rhev PATCH 3/3] sPAPR: Clear stale MSIx table during EEH reset
Bugzilla: 1213681
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: David Gibson <dgibson@redhat.com>
From: Gavin Shan <gwshan@linux.vnet.ibm.com>
The PCI device MSIx table is cleaned out in hardware after EEH PE
reset. However, we still hold the stale MSIx entries in QEMU, which
should be cleared accordingly. Otherwise, we will run into another
(recursive) EEH error and the PCI devices contained in the PE have
to be offlined exceptionally.
The patch introduces function spapr_phb_vfio_eeh_pre_reset(), which
is called by sPAPR when asserting hot or fundamental reset, to clear
stale MSIx table for VFIO PCI devices before EEH PE reset so that
MSIx table could be restored properly after EEH PE reset.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
(cherry picked from commit d46e951b62cac411ecba490a4266f4bfe771ed48)
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Upstream: 6319b1dad04e66f450fb3ac6c31d2bf3940068b8
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
hw/ppc/spapr_pci_vfio.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/hw/ppc/spapr_pci_vfio.c b/hw/ppc/spapr_pci_vfio.c
index 8104074..cca45ed 100644
--- a/hw/ppc/spapr_pci_vfio.c
+++ b/hw/ppc/spapr_pci_vfio.c
@@ -19,6 +19,7 @@
#include "hw/ppc/spapr.h"
#include "hw/pci-host/spapr.h"
+#include "hw/pci/msix.h"
#include "linux/vfio.h"
#include "hw/vfio/vfio.h"
@@ -159,6 +160,49 @@ static int spapr_phb_vfio_eeh_get_state(sPAPRPHBState *sphb, int *state)
return RTAS_OUT_SUCCESS;
}
+static void spapr_phb_vfio_eeh_clear_dev_msix(PCIBus *bus,
+ PCIDevice *pdev,
+ void *opaque)
+{
+ /* Check if the device is VFIO PCI device */
+ if (!object_dynamic_cast(OBJECT(pdev), "vfio-pci")) {
+ return;
+ }
+
+ /*
+ * The MSIx table will be cleaned out by reset. We need
+ * disable it so that it can be reenabled properly. Also,
+ * the cached MSIx table should be cleared as it's not
+ * reflecting the contents in hardware.
+ */
+ if (msix_enabled(pdev)) {
+ uint16_t flags;
+
+ flags = pci_host_config_read_common(pdev,
+ pdev->msix_cap + PCI_MSIX_FLAGS,
+ pci_config_size(pdev), 2);
+ flags &= ~PCI_MSIX_FLAGS_ENABLE;
+ pci_host_config_write_common(pdev,
+ pdev->msix_cap + PCI_MSIX_FLAGS,
+ pci_config_size(pdev), flags, 2);
+ }
+
+ msix_reset(pdev);
+}
+
+static void spapr_phb_vfio_eeh_clear_bus_msix(PCIBus *bus, void *opaque)
+{
+ pci_for_each_device(bus, pci_bus_num(bus),
+ spapr_phb_vfio_eeh_clear_dev_msix, NULL);
+}
+
+static void spapr_phb_vfio_eeh_pre_reset(sPAPRPHBState *sphb)
+{
+ PCIHostState *phb = PCI_HOST_BRIDGE(sphb);
+
+ pci_for_each_bus(phb->bus, spapr_phb_vfio_eeh_clear_bus_msix, NULL);
+}
+
static int spapr_phb_vfio_eeh_reset(sPAPRPHBState *sphb, int option)
{
sPAPRPHBVFIOState *svphb = SPAPR_PCI_VFIO_HOST_BRIDGE(sphb);
@@ -170,9 +214,11 @@ static int spapr_phb_vfio_eeh_reset(sPAPRPHBState *sphb, int option)
op.op = VFIO_EEH_PE_RESET_DEACTIVATE;
break;
case RTAS_SLOT_RESET_HOT:
+ spapr_phb_vfio_eeh_pre_reset(sphb);
op.op = VFIO_EEH_PE_RESET_HOT;
break;
case RTAS_SLOT_RESET_FUNDAMENTAL:
+ spapr_phb_vfio_eeh_pre_reset(sphb);
op.op = VFIO_EEH_PE_RESET_FUNDAMENTAL;
break;
default:
--
1.8.3.1