Ping On 1/4/21 9:54 AM, Daniel Henrique Barboza wrote:
Hi, This series is an attempt to fix https://gitlab.com/libvirt/libvirt/-/issues/72. The root issue is that, for obvious reasons, virPCIDeviceNew() requires the device to exist in the host (i.e. the config file must be present in sysfs). The unexpected absence of the device (e.g. removing the VFs from the host while a domain was using them) will make virPCIDeviceNew() return -1 in several code paths, and the effects in Libvirt can be bothersome. Patch 20 will explain it in greater detail. Changing virPCIDeviceNew() internals to not fail in this scenario would be a herculean refactor of innocent code that doesn't have anything to do with the problem. My approach here is to check if the device exists in the sysfs in key places, keeping the default virPCIDeviceNew() behavior intact. I mentioned this is patch 20 but to emphasize: this is NOT an attempt to implement surprise hostdev hotunplug support in Libvirt. Removing SR-IOVs VFs used by any domain is still not cool and should be avoided. But after this series, Libvirt can at least fall on its feet if this situation happens. The series was tested using a Mellanox MT28800 card in a Power 9 server. Daniel Henrique Barboza (20): virpci, domain_audit: use virPCIDeviceAddressAsString() qemu, lxc: move NodeDeviceGetPCIInfo() function to domain_driver.c domain_driver.c: use PCI address with virDomainDriverNodeDeviceGetPCIInfo() virpci.c: simplify virPCIDeviceNew() signature virpci: introduce virPCIDeviceExists() virhostdev.c: virHostdevGetPCIHostDevice() now reports missing device security_selinux.c: modernize set/restore hostdev subsys label functions security_dac.c: modernize hostdev label set/restore functions dac, selinux: skip setting/restoring label for absent PCI devices libvirt-nodedev.c: remove return value from virNodeDeviceFree() qemu_driver.c: modernize qemuNodeDeviceReAttach() libxl_driver.c: modernize libxlNodeDeviceReAttach() virsh-domain.c: modernize cmdDetachDevice() virhostdev.c: add virHostdevIsPCIDevice() helper qemu_cgroup.c: skip absent PCI devices in qemuTeardownHostdevCgroup() virpci.c: use virPCIDeviceAddressPtr in virPCIDeviceListFindIndex() virpci.c: use virPCIDeviceAddressPtr in virPCIDeviceListFind() virpci.c: use virPCIDeviceAddressPtr in virPCIDeviceListSteal() virpci.c: use virPCIDeviceAddressPtr in virPCIDeviceListDel() virhostdev.c: remove missing PCI devs from hostdev manager include/libvirt/libvirt-nodedev.h | 2 +- src/conf/domain_audit.c | 6 +- src/datatypes.h | 2 + src/hypervisor/domain_driver.c | 30 ++++++++++ src/hypervisor/domain_driver.h | 4 ++ src/hypervisor/virhostdev.c | 88 ++++++++++++++++++++++------ src/hypervisor/virhostdev.h | 2 + src/libvirt-nodedev.c | 15 +++-- src/libvirt_private.syms | 3 + src/libxl/libxl_driver.c | 87 ++++++++-------------------- src/node_device/node_device_udev.c | 11 ++-- src/qemu/qemu_cgroup.c | 10 ++++ src/qemu/qemu_domain_address.c | 5 +- src/qemu/qemu_driver.c | 81 +++++++------------------- src/security/security_apparmor.c | 3 +- src/security/security_dac.c | 61 ++++++++------------ src/security/security_selinux.c | 66 +++++++++------------ src/security/virt-aa-helper.c | 6 +- src/util/virnetdev.c | 3 +- src/util/virnvme.c | 5 +- src/util/virpci.c | 93 ++++++++++++++---------------- src/util/virpci.h | 14 ++--- tests/virhostdevtest.c | 3 +- tests/virpcitest.c | 35 ++++++++--- tools/virsh-domain.c | 18 ++---- 25 files changed, 325 insertions(+), 328 deletions(-)
