On Mon, May 24, 2010 at 01:39:37PM -0400, Alex Williamson wrote:
This allows libvirt to open the PCI device sysfs config file prior to dropping privileges so qemu can access the full config space. Without this, a de-privileged qemu can only access the first 64 bytes of config space.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com> ---
Note: this is still dependent on the configfd option being accepted into qemu/kvm.
v2: - fix qemuargs, two separate args (thanks Chris) - don't hardcode pci segment - error message of open() fail
v3: - add hotplug support - incorporate Daniel's comments
src/qemu/qemu_conf.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++- src/qemu/qemu_conf.h | 6 ++- src/qemu/qemu_driver.c | 28 +++++++++++++- 3 files changed, 128 insertions(+), 4 deletions(-)
@@ -7685,8 +7687,26 @@ static int qemudDomainAttachHostPciDevice(struct qemud_driver *driver, goto error; if (qemuDomainPCIAddressEnsureAddr(priv->pciaddrs, &hostdev->info) < 0) goto error; + if (qemuCmdFlags & QEMUD_CMD_FLAG_PCI_CONFIGFD) { + configfd = qemudOpenPCIConfig(hostdev); + if (configfd >= 0) { + if (virAsprintf(&configfd_name, "fd-%s", + hostdev->info.alias) < 0) { + virReportOOMError(); + goto error; + } + + qemuDomainObjEnterMonitorWithDriver(driver, vm); + if (qemuMonitorSendFileHandle(priv->mon, configfd_name, + configfd) < 0) { + qemuDomainObjExitMonitorWithDriver(driver, vm); + goto error; + } + qemuDomainObjExitMonitorWithDriver(driver, vm); + } + }
Subtle threading bug. At this point you need to add a check + if (!virDomainObjIsActive(vm)) { + qemuReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("guest unexpectedly quit during hotplug"); + goto cleanup; + } This checks for QEMU crashing after we send the file handle, which means its not valid to send the subsequent device_add command
- if (!(devstr = qemuBuildPCIHostdevDevStr(hostdev))) + if (!(devstr = qemuBuildPCIHostdevDevStr(hostdev, configfd_name))) goto error;
qemuDomainObjEnterMonitorWithDriver(driver, vm);
Aside from that addition, this patch looks good to me Regards, Daniel -- |: Red Hat, Engineering, London -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://deltacloud.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|