On 5/29/25 21:24, Steve Sistare wrote:
Do not reset a vfio-pci device during CPR.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
include/hw/pci/pci_device.h | 3 +++
hw/pci/pci.c | 5 +++++
hw/vfio/pci.c | 7 +++++++
3 files changed, 15 insertions(+)
diff --git a/include/hw/pci/pci_device.h b/include/hw/pci/pci_device.h
index e41d95b..b481c5d 100644
--- a/include/hw/pci/pci_device.h
+++ b/include/hw/pci/pci_device.h
@@ -181,6 +181,9 @@ struct PCIDevice {
uint32_t max_bounce_buffer_size;
char *sriov_pf;
+
+ /* CPR */
+ bool skip_reset_on_cpr;
};
static inline int pci_intx(PCIDevice *pci_dev)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index f5ab510..21eb11c 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -32,6 +32,7 @@
#include "hw/pci/pci_host.h"
#include "hw/qdev-properties.h"
#include "hw/qdev-properties-system.h"
+#include "migration/cpr.h"
#include "migration/qemu-file-types.h"
#include "migration/vmstate.h"
#include "net/net.h"
@@ -531,6 +532,10 @@ static void pci_reset_regions(PCIDevice *dev)
static void pci_do_device_reset(PCIDevice *dev)
{
+ if (dev->skip_reset_on_cpr && cpr_is_incoming()) {
+ return;
+ }
Since ->skip_reset_on_cpr is only true for vfio-pci devices, it could be
replaced by : object_dynamic_cast(OBJECT(dev), "vfio-pci")
Thanks,
C.
+
pci_device_deassert_intx(dev);
assert(dev->irq_state == 0);
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 7d3b9ff..56e7fdd 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3402,6 +3402,13 @@ static void vfio_instance_init(Object *obj)
/* QEMU_PCI_CAP_EXPRESS initialization does not depend on QEMU command
* line, therefore, no need to wait to realize like other devices */
pci_dev->cap_present |= QEMU_PCI_CAP_EXPRESS;
+
+ /*
+ * A device that is resuming for cpr is already configured, so do not
+ * reset it during qemu_system_reset prior to cpr load, else interrupts
+ * may be lost.
+ */
+ pci_dev->skip_reset_on_cpr = true;
}>
static void vfio_pci_base_dev_class_init(ObjectClass *klass, const void *data)
