On Mon, 20 Oct 2014 09:58:50 +0300 "Michael S. Tsirkin" <m...@redhat.com> wrote: > Current support for bus master (clearing OK bit) together with the need to > support guests which do not enable PCI bus mastering, leads to extra state in > VIRTIO_PCI_FLAG_BUS_MASTER_BUG bit, which isn't robust in case of > cross-version > migration for the case when guests use the device before setting DRIVER_OK. > > Rip out this code, and replace it: > - Modern QEMU doesn't need VIRTIO_PCI_FLAG_BUS_MASTER_BUG > so just drop it for latest machine type. > - For compat machine types, set PCI_COMMAND if DRIVER_OK > is set. > > As this is needed for 2.1 for both pc and ppc, move PC_COMPAT macros from pc.h > to a new common header. > > Reviewed-by: Greg Kurz <gk...@linux.vnet.ibm.com> > Tested-by: Greg Kurz <gk...@linux.vnet.ibm.com> > Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > --- > > Alexander, could you pls ack me merging this? > Thanks! >
This patch conflicts with the following commit in Alex's ppc-next branch: commit 6dd65a940532eaac42a302c30964b0d42967e187 Author: David Gibson <da...@gibson.dropbear.id.au> Date: Mon Sep 8 15:30:31 2014 +1000 spapr: Cleanup machine naming conventions, and prepare for 2.2 release Easy to fix though. Alex, I can send the rebased version if you want. Cheers. -- Greg > > changes from v2: > drop default = -1 from ppc - was a typo, reported by Greg > > hw/virtio/virtio-pci.h | 5 +++++ > include/hw/compat.h | 16 ++++++++++++++++ > include/hw/i386/pc.h | 10 ++-------- > hw/i386/pc_piix.c | 2 +- > hw/i386/pc_q35.c | 2 +- > hw/ppc/spapr.c | 7 +++++++ > hw/virtio/virtio-pci.c | 29 +++++++++++------------------ > 7 files changed, 43 insertions(+), 28 deletions(-) > create mode 100644 include/hw/compat.h > > diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h > index 1cea157..8873b6d 100644 > --- a/hw/virtio/virtio-pci.h > +++ b/hw/virtio/virtio-pci.h > @@ -53,6 +53,11 @@ typedef struct VirtioBusClass VirtioPCIBusClass; > #define VIRTIO_PCI_BUS_CLASS(klass) \ > OBJECT_CLASS_CHECK(VirtioPCIBusClass, klass, TYPE_VIRTIO_PCI_BUS) > > +/* Need to activate work-arounds for buggy guests at vmstate load. */ > +#define VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT 0 > +#define VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION \ > + (1 << VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT) > + > /* Performance improves when virtqueue kick processing is decoupled from the > * vcpu thread using ioeventfd for some devices. */ > #define VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT 1 > diff --git a/include/hw/compat.h b/include/hw/compat.h > new file mode 100644 > index 0000000..47f6ff5 > --- /dev/null > +++ b/include/hw/compat.h > @@ -0,0 +1,16 @@ > +#ifndef HW_COMPAT_H > +#define HW_COMPAT_H > + > +#define HW_COMPAT_2_1 \ > + {\ > + .driver = "intel-hda",\ > + .property = "old_msi_addr",\ > + .value = "on",\ > + },\ > + {\ > + .driver = "virtio-pci",\ > + .property = "virtio-pci-bus-master-bug-migration",\ > + .value = "on",\ > + } > + > +#endif /* HW_COMPAT_H */ > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h > index bae023a..82ad046 100644 > --- a/include/hw/i386/pc.h > +++ b/include/hw/i386/pc.h > @@ -14,6 +14,7 @@ > #include "sysemu/sysemu.h" > #include "hw/pci/pci.h" > #include "hw/boards.h" > +#include "hw/compat.h" > > #define HPET_INTCAP "hpet-intcap" > > @@ -307,15 +308,8 @@ int e820_add_entry(uint64_t, uint64_t, uint32_t); > int e820_get_num_entries(void); > bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *); > > -#define PC_COMPAT_2_1 \ > - {\ > - .driver = "intel-hda",\ > - .property = "old_msi_addr",\ > - .value = "on",\ > - } > - > #define PC_COMPAT_2_0 \ > - PC_COMPAT_2_1, \ > + HW_COMPAT_2_1, \ > {\ > .driver = "virtio-scsi-pci",\ > .property = "any_layout",\ > diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c > index 553afdd..a1634ab 100644 > --- a/hw/i386/pc_piix.c > +++ b/hw/i386/pc_piix.c > @@ -502,7 +502,7 @@ static QEMUMachine pc_i440fx_machine_v2_1 = { > .name = "pc-i440fx-2.1", > .init = pc_init_pci, > .compat_props = (GlobalProperty[]) { > - PC_COMPAT_2_1, > + HW_COMPAT_2_1, > { /* end of list */ } > }, > }; > diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c > index a199043..f330f7a 100644 > --- a/hw/i386/pc_q35.c > +++ b/hw/i386/pc_q35.c > @@ -365,7 +365,7 @@ static QEMUMachine pc_q35_machine_v2_1 = { > .name = "pc-q35-2.1", > .init = pc_q35_init, > .compat_props = (GlobalProperty[]) { > - PC_COMPAT_2_1, > + HW_COMPAT_2_1, > { /* end of list */ } > }, > }; > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c > index 2becc9f..623f626 100644 > --- a/hw/ppc/spapr.c > +++ b/hw/ppc/spapr.c > @@ -57,6 +57,8 @@ > #include "trace.h" > #include "hw/nmi.h" > > +#include "hw/compat.h" > + > #include <libfdt.h> > > /* SLOF memory layout: > @@ -1689,10 +1691,15 @@ static const TypeInfo spapr_machine_info = { > static void spapr_machine_2_1_class_init(ObjectClass *oc, void *data) > { > MachineClass *mc = MACHINE_CLASS(oc); > + static GlobalProperty compat_props[] = { > + HW_COMPAT_2_1, > + { /* end of list */ }1 > + }; > > mc->name = "pseries-2.1"; > mc->desc = "pSeries Logical Partition (PAPR compliant) v2.1"; > mc->is_default = 0; > + mc->compat_props = compat_props; > } > > static const TypeInfo spapr_machine_2_1_info = { > diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c > index a827cd4..a499a3c 100644 > --- a/hw/virtio/virtio-pci.c > +++ b/hw/virtio/virtio-pci.c > @@ -86,9 +86,6 @@ > * 12 is historical, and due to x86 page size. */ > #define VIRTIO_PCI_QUEUE_ADDR_SHIFT 12 > > -/* Flags track per-device state like workarounds for quirks in older guests. > */ > -#define VIRTIO_PCI_FLAG_BUS_MASTER_BUG (1 << 0) > - > static void virtio_pci_bus_new(VirtioBusState *bus, size_t bus_size, > VirtIOPCIProxy *dev); > > @@ -323,14 +320,6 @@ static void virtio_ioport_write(void *opaque, uint32_t > addr, uint32_t val) > proxy->pci_dev.config[PCI_COMMAND] | > PCI_COMMAND_MASTER, 1); > } > - > - /* Linux before 2.6.34 sets the device as OK without enabling > - the PCI device bus master bit. In this case we need to disable > - some safety checks. */ > - if ((val & VIRTIO_CONFIG_S_DRIVER_OK) && > - !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { > - proxy->flags |= VIRTIO_PCI_FLAG_BUS_MASTER_BUG; > - } > break; > case VIRTIO_MSI_CONFIG_VECTOR: > msix_vector_unuse(&proxy->pci_dev, vdev->config_vector); > @@ -483,8 +472,7 @@ static void virtio_write_config(PCIDevice *pci_dev, > uint32_t address, > pci_default_write_config(pci_dev, address, val, len); > > if (range_covers_byte(address, len, PCI_COMMAND) && > - !(pci_dev->config[PCI_COMMAND] & PCI_COMMAND_MASTER) &&1 > - !(proxy->flags & VIRTIO_PCI_FLAG_BUS_MASTER_BUG)) { > + !(pci_dev->config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { > virtio_pci_stop_ioeventfd(proxy); > virtio_set_status(vdev, vdev->status & ~VIRTIO_CONFIG_S_DRIVER_OK); > } > @@ -895,11 +883,15 @@ static void virtio_pci_vmstate_change(DeviceState *d, > bool running) > VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus); > > if (running) { > - /* Try to find out if the guest has bus master disabled, but is > - in ready state. Then we have a buggy guest OS. */ > - if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) && > + /* Old QEMU versions did not set bus master enable on status write. > + * Detect DRIVER set and enable it. > + */ > + if ((proxy->flags & VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION) && > + (vdev->status & VIRTIO_CONFIG_S_DRIVER) && > !(proxy->pci_dev.config[PCI_COMMAND] & PCI_COMMAND_MASTER)) { > - proxy->flags |= VIRTIO_PCI_FLAG_BUS_MASTER_BUG; > + pci_default_write_config(&proxy->pci_dev, PCI_COMMAND, > + proxy->pci_dev.config[PCI_COMMAND] | > + PCI_COMMAND_MASTER, 1); > } > virtio_pci_start_ioeventfd(proxy); > } else { > @@ -1040,10 +1032,11 @@ static void virtio_pci_reset(DeviceState *qdev) > virtio_pci_stop_ioeventfd(proxy); > virtio_bus_reset(bus); > msix_unuse_all_vectors(&proxy->pci_dev); > - proxy->flags &= ~VIRTIO_PCI_FLAG_BUS_MASTER_BUG; > } > > static Property virtio_pci_properties[] = { > + DEFINE_PROP_BIT("virtio-pci-bus-master-bug-migration", VirtIOPCIProxy, > flags, > + VIRTIO_PCI_FLAG_BUS_MASTER_BUG_MIGRATION_BIT, false), > DEFINE_VIRTIO_COMMON_FEATURES(VirtIOPCIProxy, host_features), > DEFINE_PROP_END_OF_LIST(), > };