On 2/4/2025 9:14 AM, Cédric Le Goater wrote:
On 1/29/25 15:43, Steve Sistare wrote:
Do not reset a vfio-pci device during CPR.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
hw/pci/pci.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 2afa423..16b4f71 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/misc.h"
#include "migration/qemu-file-types.h"
#include "migration/vmstate.h"
#include "net/net.h"
@@ -459,6 +460,18 @@ static void pci_reset_regions(PCIDevice *dev)
static void pci_do_device_reset(PCIDevice *dev)
{
+ /*
+ * A PCI device that is resuming for cpr is already configured, so do
+ * not reset it here when we are called from qemu_system_reset prior to
+ * cpr load, else interrupts may be lost for vfio-pci devices. It is
+ * safe to skip this reset for all PCI devices, because cpr load will set
+ * all fields that would have been set here.
+ */
+ MigMode mode = migrate_mode();
+ if (mode == MIG_MODE_CPR_TRANSFER) {
+ return;
+ }
Please use cpr_needed_for_reuse(). Or an appropriate helper.
OK.
I would the test under pci_device_reset() and avoid calling
pci_do_device_reset().
pci_do_device_reset is also called from pcibus_reset_hold.
- Steve
pci_device_deassert_intx(dev);
assert(dev->irq_state == 0);
