Re: live migrating hvm from 4.4 to 4.5 fails due to kvmvapic

[Olaf Hering <olaf@aepfle.de>]

On Thu, May 12, Olaf Hering wrote:

> One thing to fix it in staging-4.5 is to introduce a dummy device which
> handles a section named "kvm-tpr-opt". I already have a hack which does
> that, and the migration proceeds. I will propose a patch to deal with
> this part of the bug.

Something like shown below.

> Unfortunately later the VM appears to be alive, but nothing happens in
> it. I assume it gets no further interrupts. Guess I need help with this
> part of the bug.


Olaf

---
 hw/i386/Makefile.objs    |    1 
 hw/i386/xen44_kvmvapic.c |  147 +++++++++++++++++++++++++++++++++++++++++++++++
 xen-hvm.c                |    3 
 3 files changed, 151 insertions(+)

--- a/hw/i386/Makefile.objs
+++ b/hw/i386/Makefile.objs
@@ -5,6 +5,7 @@ obj-y += pc_sysfw.o
 obj-$(CONFIG_XEN) += ../xenpv/ xen/
 
 obj-y += kvmvapic.o
+obj-y += xen44_kvmvapic.o
 obj-y += acpi-build.o
 obj-y += bios-linker-loader.o
 hw/i386/acpi-build.o: hw/i386/acpi-build.c hw/i386/acpi-dsdt.hex \
--- /dev/null
+++ b/hw/i386/xen44_kvmvapic.c
@@ -0,0 +1,147 @@
+/*
+ * Copy of kvmvapic to allow migration from xen-4.4 qemu-xen with "kvm-tpr-opt"
+ *
+ * Copyright (C) 2007-2008 Qumranet Technologies
+ * Copyright (C) 2012      Jan Kiszka, Siemens AG
+ *
+ * This work is licensed under the terms of the GNU GPL version 2, or
+ * (at your option) any later version. See the COPYING file in the
+ * top-level directory.
+ */
+#include "sysemu/sysemu.h"
+#include "sysemu/cpus.h"
+#include "sysemu/kvm.h"
+#include "hw/i386/apic_internal.h"
+#include "hw/sysbus.h"
+#include "hw/xen/xen.h"
+
+typedef struct VAPICHandlers {
+    uint32_t set_tpr;
+    uint32_t set_tpr_eax;
+    uint32_t get_tpr[8];
+    uint32_t get_tpr_stack;
+} QEMU_PACKED VAPICHandlers;
+
+typedef struct GuestROMState {
+    char signature[8];
+    uint32_t vaddr;
+    uint32_t fixup_start;
+    uint32_t fixup_end;
+    uint32_t vapic_vaddr;
+    uint32_t vapic_size;
+    uint32_t vcpu_shift;
+    uint32_t real_tpr_addr;
+    VAPICHandlers up;
+    VAPICHandlers mp;
+} QEMU_PACKED GuestROMState;
+
+typedef struct VAPICROMState {
+    SysBusDevice busdev;
+    MemoryRegion io;
+    MemoryRegion rom;
+    uint32_t state;
+    uint32_t rom_state_paddr;
+    uint32_t rom_state_vaddr;
+    uint32_t vapic_paddr;
+    uint32_t real_tpr_addr;
+    GuestROMState rom_state;
+    size_t rom_size;
+    bool rom_mapped_writable;
+} VAPICROMState;
+
+#define TYPE_XEN_KVMVAPIC "xen_kvmvapic" /* copy of "kvmvapic" */
+
+static void xen44_vapic_realize(DeviceState *dev, Error **errp)
+{
+    fprintf(stderr, "%s(%u) dev %p\n", __func__, __LINE__, dev);
+}
+
+static int xen44_vapic_post_load(void *opaque, int version_id)
+{
+    if (xen_enabled()) {
+        int i;
+        fprintf(stderr, "%s(%u) %p 0x%x\n", __func__, __LINE__, opaque, version_id);
+        for (i = 12; i > 0; i--) {
+	    sleep(1);
+            fprintf(stderr, "%s(%u) sleep %d %ld\n", __func__, __LINE__, i, (long)getpid());
+	}
+    }
+    return 0;
+}
+
+static const VMStateDescription vmstate_handlers = {
+    .name = "kvmvapic-handlers",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(set_tpr, VAPICHandlers),
+        VMSTATE_UINT32(set_tpr_eax, VAPICHandlers),
+        VMSTATE_UINT32_ARRAY(get_tpr, VAPICHandlers, 8),
+        VMSTATE_UINT32(get_tpr_stack, VAPICHandlers),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_guest_rom = {
+    .name = "kvmvapic-guest-rom",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UNUSED(8),     /* signature */
+        VMSTATE_UINT32(vaddr, GuestROMState),
+        VMSTATE_UINT32(fixup_start, GuestROMState),
+        VMSTATE_UINT32(fixup_end, GuestROMState),
+        VMSTATE_UINT32(vapic_vaddr, GuestROMState),
+        VMSTATE_UINT32(vapic_size, GuestROMState),
+        VMSTATE_UINT32(vcpu_shift, GuestROMState),
+        VMSTATE_UINT32(real_tpr_addr, GuestROMState),
+        VMSTATE_STRUCT(up, GuestROMState, 0, vmstate_handlers, VAPICHandlers),
+        VMSTATE_STRUCT(mp, GuestROMState, 0, vmstate_handlers, VAPICHandlers),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_xen44_vapic = {
+    .name = "kvm-tpr-opt",      /* compatible with qemu-kvm VAPIC */
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .post_load = xen44_vapic_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_STRUCT(rom_state, VAPICROMState, 0, vmstate_guest_rom,
+                       GuestROMState),
+        VMSTATE_UINT32(state, VAPICROMState),
+        VMSTATE_UINT32(real_tpr_addr, VAPICROMState),
+        VMSTATE_UINT32(rom_state_vaddr, VAPICROMState),
+        VMSTATE_UINT32(vapic_paddr, VAPICROMState),
+        VMSTATE_UINT32(rom_state_paddr, VAPICROMState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void xen44_vapic_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    fprintf(stderr, "%s(%u) klass %p data %p\n", __func__, __LINE__, klass, data);
+    dc->vmsd    = &vmstate_xen44_vapic;
+    dc->realize = xen44_vapic_realize;
+}
+
+static const TypeInfo xen44_vapic_type = {
+    .name          = TYPE_XEN_KVMVAPIC,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(VAPICROMState),
+    .class_init    = xen44_vapic_class_init,
+};
+
+static void xen44_vapic_register(void)
+{
+    fprintf(stderr, "%s(%u)\n", __func__, __LINE__);
+    type_register_static(&xen44_vapic_type);
+}
+
+type_init(xen44_vapic_register);
+
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -15,6 +15,7 @@
 #include "hw/i386/apic-msidef.h"
 #include "hw/xen/xen_common.h"
 #include "hw/xen/xen_backend.h"
+#include "hw/sysbus.h"
 #include "qmp-commands.h"
 
 #include "sysemu/char.h"
@@ -161,6 +162,8 @@ static void xen_set_irq(void *opaque, in
 
 qemu_irq *xen_interrupt_controller_init(void)
 {
+    DeviceState *vapic = sysbus_create_simple("kvmvapic", -1, NULL);
+
     return qemu_allocate_irqs(xen_set_irq, NULL, 16);
 }
 

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel