pxb/pxb-pcie/pxb-cxl devices currently doesn't have vmstate description So the state of device is not preserved during migration and guest can notice that as change of PCI_COMMAND_* registers state.
The diff of lspci output before and after migration: 00:03.0 Host bridge [0600]: Red Hat, Inc. QEMU PCIe Expander bridge [1b36:000b] Subsystem: Red Hat, Inc QEMU PCIe Expander bridge [1af4:1100] - Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx- + Control: I/O- Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap- 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Add VMStateDescription to pxb devices so their state is transferred during migrations. For saving migration compatibility add 'x-config-reg-migration-enabled' property to pxb devices and disable it for all released machine types. Signed-off-by: Andrey Ryabinin <a...@yandex-team.com> --- hw/core/machine.c | 3 +++ hw/pci-bridge/pci_expander_bridge.c | 24 ++++++++++++++++++++++++ include/hw/pci/pci_bridge.h | 1 + 3 files changed, 28 insertions(+) diff --git a/hw/core/machine.c b/hw/core/machine.c index a673302ccec..071853469e2 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -43,6 +43,9 @@ GlobalProperty hw_compat_7_0[] = { { "arm-gicv3-common", "force-8-bit-prio", "on" }, { "nvme-ns", "eui64-default", "on"}, + { "pxb", "x-config-reg-migration-enabled", "off" }, + { "pxb-cxl", "x-config-reg-migration-enabled", "off" }, + { "pxb-pcie", "x-config-reg-migration-enabled", "off" }, }; const size_t hw_compat_7_0_len = G_N_ELEMENTS(hw_compat_7_0); diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c index c9e817aa586..a3680d4d045 100644 --- a/hw/pci-bridge/pci_expander_bridge.c +++ b/hw/pci-bridge/pci_expander_bridge.c @@ -23,6 +23,7 @@ #include "qemu/error-report.h" #include "qemu/module.h" #include "sysemu/numa.h" +#include "migration/vmstate.h" #include "hw/boards.h" #include "qom/object.h" @@ -404,9 +405,29 @@ static Property pxb_dev_properties[] = { DEFINE_PROP_UINT8("bus_nr", PXBDev, bus_nr, 0), DEFINE_PROP_UINT16("numa_node", PXBDev, numa_node, NUMA_NODE_UNASSIGNED), DEFINE_PROP_BOOL("bypass_iommu", PXBDev, bypass_iommu, false), + DEFINE_PROP_BOOL("x-config-reg-migration-enabled", PXBDev, + migratable, true), DEFINE_PROP_END_OF_LIST(), }; +static bool pxb_vmstate_needed(void *opaque) +{ + PXBDev *pxb = opaque; + + return pxb->migratable; +} + +static const VMStateDescription vmstate_pxb_device = { + .name = "pxb-pci", + .needed = pxb_vmstate_needed, + .version_id = 1, + .minimum_version_id = 1, + .fields = (VMStateField[]) { + VMSTATE_PCI_DEVICE(parent_obj, PXBDev), + VMSTATE_END_OF_LIST() + } +}; + static void pxb_dev_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); @@ -422,6 +443,7 @@ static void pxb_dev_class_init(ObjectClass *klass, void *data) device_class_set_props(dc, pxb_dev_properties); dc->hotpluggable = false; set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories); + dc->vmsd = &vmstate_pxb_device; } static const TypeInfo pxb_dev_info = { @@ -460,6 +482,7 @@ static void pxb_pcie_dev_class_init(ObjectClass *klass, void *data) device_class_set_props(dc, pxb_dev_properties); dc->hotpluggable = false; set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories); + dc->vmsd = &vmstate_pxb_device; } static const TypeInfo pxb_pcie_dev_info = { @@ -504,6 +527,7 @@ static void pxb_cxl_dev_class_init(ObjectClass *klass, void *data) /* Host bridges aren't hotpluggable. FIXME: spec reference */ dc->hotpluggable = false; dc->reset = pxb_dev_reset; + dc->vmsd = &vmstate_pxb_device; } static const TypeInfo pxb_cxl_dev_info = { diff --git a/include/hw/pci/pci_bridge.h b/include/hw/pci/pci_bridge.h index ba4bafac7c2..404dc02e36e 100644 --- a/include/hw/pci/pci_bridge.h +++ b/include/hw/pci/pci_bridge.h @@ -91,6 +91,7 @@ struct PXBDev { uint8_t bus_nr; uint16_t numa_node; bool bypass_iommu; + bool migratable; struct cxl_dev { CXLHost *cxl_host_bridge; /* Pointer to a CXLHost */ } cxl; -- 2.35.1