There are PCI devices with pretty large non-prefetchable memory, for instance: Memory at 9d800000 (64-bit, non-prefetchable) [size=8M] Memory at a6800000 (64-bit, non-prefetchable) [size=16K] For cold plugged devices this is not a problem, because firmware sets PCI controllers in a way that make devices behind them just work. Problem arises if such PCI device is to be hot plugged. Since the PCI device wasn't present at cold boot, firmware could not take it into calculations and the amount of reserved memory is not sufficient. Introduce a know that allows users overriding value computed by FW and thus allow hot plug of such PCI devices. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- docs/formatdomain.rst | 6 ++++++ src/conf/domain_conf.c | 9 +++++++++ src/conf/domain_conf.h | 3 +++ src/conf/schemas/domaincommon.rng | 5 +++++ tests/qemuxmlconfdata/q35-usb2.x86_64-latest.xml | 2 +- tests/qemuxmlconfdata/q35-usb2.xml | 2 +- 6 files changed, 25 insertions(+), 2 deletions(-) diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index e2f66b982c..de7036e49c 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -4153,6 +4153,12 @@ generated by libvirt. :since:`Since 1.2.19 (QEMU only)`. ``index`` pci-root controllers for pSeries guests use this attribute to record the order they will show up in the guest. :since:`Since 3.6.0` +``memReserve`` + Some PCI devices have non-prefetchable memory bar larger than 2MiB. Use this + attribute to override value computed by firmware and thus make controller + reserve more memory (in KiB) so that such PCI device can be hot plugged. + For cold plugged PCI devices firmware recognizes this and computes correct + value. :since:`Since 10.3.0` For machine types which provide an implicit PCI bus, the pci-root controller with index=0 is auto-added and required to use PCI devices. pci-root has no diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 48c5d546da..a0912062ff 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -8528,6 +8528,11 @@ virDomainControllerDefParseXML(virDomainXMLOption *xmlopt, &def->opts.pciopts.targetIndex, def->opts.pciopts.targetIndex) < 0) return NULL; + + if (virXMLPropULongLong(targetNodes[0], "memReserve", 0, + VIR_XML_PROP_NONZERO, + &def->opts.pciopts.memReserve) < 0) + return NULL; } } @@ -23095,6 +23100,10 @@ virDomainControllerDefFormatPCI(virBuffer *buf, virBufferAsprintf(&targetAttrBuf, " hotplug='%s'", virTristateSwitchTypeToString(def->opts.pciopts.hotplug)); } + if (def->opts.pciopts.memReserve) { + virBufferAsprintf(&targetAttrBuf, " memReserve='%llu'", + def->opts.pciopts.memReserve); + } if (def->opts.pciopts.numaNode != -1) virBufferAsprintf(&targetChildBuf, "<node>%d</node>\n", def->opts.pciopts.numaNode); diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h index 5925faaf1a..356c25405b 100644 --- a/src/conf/domain_conf.h +++ b/src/conf/domain_conf.h @@ -738,6 +738,9 @@ struct _virDomainPCIControllerOpts { */ int numaNode; virTristateSwitch hotplug; /* 'off' to prevent hotplug/unplug, default 'on' */ + + unsigned long long memReserve; /* used by pci-bridge and pcie-root-port, + 0 == undef, KiB */ }; struct _virDomainUSBControllerOpts { diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng index f386e46fae..d84e030255 100644 --- a/src/conf/schemas/domaincommon.rng +++ b/src/conf/schemas/domaincommon.rng @@ -2897,6 +2897,11 @@ <ref name="unsignedInt"/> </element> </optional> + <optional> + <attribute name="memReserve"> + <ref name="unsignedLong"/> + </attribute> + </optional> </element> </optional> <!-- *-root controllers have an optional element "pcihole64"--> diff --git a/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.xml b/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.xml index b860ae2dee..2bbbbfe346 100644 --- a/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.xml +++ b/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.xml @@ -30,7 +30,7 @@ </controller> <controller type='pci' index='2' model='pci-bridge'> <model name='pci-bridge'/> - <target chassisNr='56'/> + <target chassisNr='56' memReserve='8196'/> <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/> </controller> <controller type='usb' index='0' model='ich9-ehci1'> diff --git a/tests/qemuxmlconfdata/q35-usb2.xml b/tests/qemuxmlconfdata/q35-usb2.xml index 571782a17c..4f5a5580ac 100644 --- a/tests/qemuxmlconfdata/q35-usb2.xml +++ b/tests/qemuxmlconfdata/q35-usb2.xml @@ -25,7 +25,7 @@ </controller> <controller type='pci' index='2' model='pci-bridge'> <model name='pci-bridge'/> - <target chassisNr='56'/> + <target chassisNr='56' memReserve='8196'/> </controller> <controller type='usb' index='0' model='ich9-ehci1'/> <controller type='usb' index='0' model='ich9-uhci1'/> -- 2.43.2

Only two controller models allow setting mem-reserve: pcie-root-port and pci-bridge. Reflect this fact during validation. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- src/qemu/qemu_validate.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c index de0867c4b1..fd7b90e47d 100644 --- a/src/qemu/qemu_validate.c +++ b/src/qemu/qemu_validate.c @@ -4091,6 +4091,31 @@ qemuValidateDomainDeviceDefControllerPCI(const virDomainControllerDef *cont, } } + /* memReserve */ + switch ((virDomainControllerModelPCI) cont->model) { + case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_ROOT_PORT: + case VIR_DOMAIN_CONTROLLER_MODEL_PCI_BRIDGE: + break; + case VIR_DOMAIN_CONTROLLER_MODEL_PCI_ROOT: + case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_SWITCH_DOWNSTREAM_PORT: + case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_ROOT: + case VIR_DOMAIN_CONTROLLER_MODEL_DMI_TO_PCI_BRIDGE: + case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_TO_PCI_BRIDGE: + case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_SWITCH_UPSTREAM_PORT: + case VIR_DOMAIN_CONTROLLER_MODEL_PCI_EXPANDER_BUS: + case VIR_DOMAIN_CONTROLLER_MODEL_PCIE_EXPANDER_BUS: + if (pciopts->memReserve) { + virReportControllerInvalidOption(cont, model, modelName, "memReserve"); + return -1; + } + break; + + case VIR_DOMAIN_CONTROLLER_MODEL_PCI_DEFAULT: + case VIR_DOMAIN_CONTROLLER_MODEL_PCI_LAST: + default: + virReportEnumRangeError(virDomainControllerModelPCI, cont->model); + } + /* QEMU device availability */ if (cap < 0) { virReportError(VIR_ERR_INTERNAL_ERROR, -- 2.43.2

Pretty straightforward. Just put mem-reserve attribute whenever it's set. Previous commit ensures it's set only for valid controller models. Resolves: https://issues.redhat.com/browse/RHEL-7461 Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- src/qemu/qemu_command.c | 3 +++ tests/qemuxmlconfdata/q35-usb2.x86_64-latest.args | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 9d4563861f..8d4442c360 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -2776,6 +2776,7 @@ qemuBuildControllerPCIDevProps(virDomainControllerDef *def, if (virJSONValueObjectAdd(&props, "s:driver", modelName, "i:chassis_nr", pciopts->chassisNr, + "P:mem-reserve", pciopts->memReserve * 1024, "s:id", def->info.alias, NULL) < 0) return -1; @@ -2816,6 +2817,7 @@ qemuBuildControllerPCIDevProps(virDomainControllerDef *def, "i:chassis", pciopts->chassis, "s:id", def->info.alias, "T:hotplug", pciopts->hotplug, + "P:mem-reserve", pciopts->memReserve * 1024, NULL) < 0) return -1; @@ -2824,6 +2826,7 @@ qemuBuildControllerPCIDevProps(virDomainControllerDef *def, if (virJSONValueObjectAdd(&props, "s:driver", modelName, "i:index", pciopts->targetIndex, + "P:mem-reserve", pciopts->memReserve * 1024, "s:id", def->info.alias, NULL) < 0) return -1; diff --git a/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.args b/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.args index 717e97706e..86776e45f5 100644 --- a/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.args +++ b/tests/qemuxmlconfdata/q35-usb2.x86_64-latest.args @@ -27,7 +27,7 @@ XDG_CONFIG_HOME=/var/lib/libvirt/qemu/domain--1-q35-test/.config \ -no-shutdown \ -boot strict=on \ -device '{"driver":"i82801b11-bridge","id":"pci.1","bus":"pcie.0","addr":"0x1e"}' \ --device '{"driver":"pci-bridge","chassis_nr":56,"id":"pci.2","bus":"pci.1","addr":"0x0"}' \ +-device '{"driver":"pci-bridge","chassis_nr":56,"mem-reserve":8392704,"id":"pci.2","bus":"pci.1","addr":"0x0"}' \ -device '{"driver":"ich9-usb-ehci1","id":"usb","bus":"pcie.0","addr":"0x1d.0x7"}' \ -device '{"driver":"ich9-usb-uhci1","masterbus":"usb.0","firstport":0,"bus":"pcie.0","multifunction":true,"addr":"0x1d"}' \ -device '{"driver":"ich9-usb-uhci2","masterbus":"usb.0","firstport":2,"bus":"pcie.0","addr":"0x1d.0x1"}' \ -- 2.43.2