From 3deffc03c2e9b0053eec5aeb5b5d633dfe29f499 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Wed, 6 Apr 2022 14:58:12 -0400 Subject: [PATCH 1/3] acpi: fix acpi_index migration MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Peter Xu RH-MergeRequest: 343: acpi: fix acpi_index migration RH-Jira: RHEL-20189 RH-Acked-by: Leonardo Brás RH-Acked-by: Igor Mammedov RH-Acked-by: Prasad Pandit RH-Commit: [1/2] c5b9cdf5791cd856207b7df7e2ef5df360ec8de4 vmstate_acpi_pcihp_use_acpi_index() was expecting AcpiPciHpState as state but it actually received PIIX4PMState, because VMSTATE_PCI_HOTPLUG is a macro and not another struct. So it ended up accessing random pointer, which resulted in 'false' return value and acpi_index field wasn't ever sent. However in 7.0 that pointer de-references to value > 0, and destination QEMU starts to expect the field which isn't sent in migratioon stream from older QEMU (6.2 and older). As result migration fails with: qemu-system-x86_64: Missing section footer for 0000:00:01.3/piix4_pm qemu-system-x86_64: load of migration failed: Invalid argument In addition with QEMU-6.2, destination due to not expected state, also never expects the acpi_index field in migration stream. Q35 is not affected as it always sends/expects the field as long as acpi based PCI hotplug is enabled. Fix issue by introducing compat knob to never send/expect acpi_index in migration stream for 6.2 and older PC machine types and always send it for 7.0 and newer PC machine types. Diagnosed-by: Dr. David Alan Gilbert Fixes: b32bd76 ("pci: introduce acpi-index property for PCI device") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/932 Signed-off-by: Igor Mammedov Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Peter Maydell (cherry picked from commit a83c2844903c45aa7d32cdd17305f23ce2c56ab9) Signed-off-by: Peter Xu --- hw/acpi/acpi-pci-hotplug-stub.c | 4 ---- hw/acpi/pcihp.c | 6 ------ hw/acpi/piix4.c | 15 ++++++++++++++- hw/core/machine.c | 5 +++++ include/hw/acpi/pcihp.h | 2 -- 5 files changed, 19 insertions(+), 13 deletions(-) diff --git a/hw/acpi/acpi-pci-hotplug-stub.c b/hw/acpi/acpi-pci-hotplug-stub.c index 734e4c5986..a43f6dafc9 100644 --- a/hw/acpi/acpi-pci-hotplug-stub.c +++ b/hw/acpi/acpi-pci-hotplug-stub.c @@ -41,7 +41,3 @@ void acpi_pcihp_reset(AcpiPciHpState *s, bool acpihp_root_off) return; } -bool vmstate_acpi_pcihp_use_acpi_index(void *opaque, int version_id) -{ - return false; -} diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c index be0e846b34..ec861661c3 100644 --- a/hw/acpi/pcihp.c +++ b/hw/acpi/pcihp.c @@ -559,12 +559,6 @@ void acpi_pcihp_init(Object *owner, AcpiPciHpState *s, PCIBus *root_bus, OBJ_PROP_FLAG_READ); } -bool vmstate_acpi_pcihp_use_acpi_index(void *opaque, int version_id) -{ - AcpiPciHpState *s = opaque; - return s->acpi_index; -} - const VMStateDescription vmstate_acpi_pcihp_pci_status = { .name = "acpi_pcihp_pci_status", .version_id = 1, diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c index 8d6011c0a3..033e75ce5b 100644 --- a/hw/acpi/piix4.c +++ b/hw/acpi/piix4.c @@ -82,6 +82,7 @@ struct PIIX4PMState { AcpiPciHpState acpi_pci_hotplug; bool use_acpi_hotplug_bridge; bool use_acpi_root_pci_hotplug; + bool not_migrate_acpi_index; uint8_t disable_s3; uint8_t disable_s4; @@ -269,6 +270,16 @@ static bool piix4_vmstate_need_smbus(void *opaque, int version_id) return pm_smbus_vmstate_needed(); } +/* + * This is a fudge to turn off the acpi_index field, + * whose test was always broken on piix4 with 6.2 and older machine types. + */ +static bool vmstate_test_migrate_acpi_index(void *opaque, int version_id) +{ + PIIX4PMState *s = PIIX4_PM(opaque); + return s->use_acpi_hotplug_bridge && !s->not_migrate_acpi_index; +} + /* qemu-kvm 1.2 uses version 3 but advertised as 2 * To support incoming qemu-kvm 1.2 migration, change version_id * and minimum_version_id to 2 below (which breaks migration from @@ -299,7 +310,7 @@ static const VMStateDescription vmstate_acpi = { struct AcpiPciHpPciStatus), VMSTATE_PCI_HOTPLUG(acpi_pci_hotplug, PIIX4PMState, vmstate_test_use_acpi_hotplug_bridge, - vmstate_acpi_pcihp_use_acpi_index), + vmstate_test_migrate_acpi_index), VMSTATE_END_OF_LIST() }, .subsections = (const VMStateDescription*[]) { @@ -654,6 +665,8 @@ static Property piix4_pm_properties[] = { DEFINE_PROP_BOOL("memory-hotplug-support", PIIX4PMState, acpi_memory_hotplug.is_enabled, true), DEFINE_PROP_BOOL("smm-compat", PIIX4PMState, smm_compat, false), + DEFINE_PROP_BOOL("x-not-migrate-acpi-index", PIIX4PMState, + not_migrate_acpi_index, false), DEFINE_PROP_END_OF_LIST(), }; diff --git a/hw/core/machine.c b/hw/core/machine.c index 76fcabec7a..2724f6848a 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -331,6 +331,11 @@ GlobalProperty hw_compat_rhel_7_1[] = { }; const size_t hw_compat_rhel_7_1_len = G_N_ELEMENTS(hw_compat_rhel_7_1); +GlobalProperty hw_compat_6_2[] = { + { "PIIX4_PM", "x-not-migrate-acpi-index", "on"}, +}; +const size_t hw_compat_6_2_len = G_N_ELEMENTS(hw_compat_6_2); + GlobalProperty hw_compat_6_1[] = { { "vhost-user-vsock-device", "seqpacket", "off" }, { "nvme-ns", "shared", "off" }, diff --git a/include/hw/acpi/pcihp.h b/include/hw/acpi/pcihp.h index af1a169fc3..7e268c2c9c 100644 --- a/include/hw/acpi/pcihp.h +++ b/include/hw/acpi/pcihp.h @@ -73,8 +73,6 @@ void acpi_pcihp_reset(AcpiPciHpState *s, bool acpihp_root_off); extern const VMStateDescription vmstate_acpi_pcihp_pci_status; -bool vmstate_acpi_pcihp_use_acpi_index(void *opaque, int version_id); - #define VMSTATE_PCI_HOTPLUG(pcihp, state, test_pcihp, test_acpi_index) \ VMSTATE_UINT32_TEST(pcihp.hotplug_select, state, \ test_pcihp), \ -- 2.41.0