Re: [libvirt] [PATCH v4 03/10] Refuse to reattach from vfio if the iommu group is in use by any domain

It is incorrect to attempt the device reattach of a function, when some other domain is using some functions belonging to the same iommu group. Signed-off-by: Shivaprasad G Bhat <sbhat(a)linux.vnet.ibm.com&gt; --- src/util/virhostdev.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/src/util/virhostdev.c b/src/util/virhostdev.c index de029a0..f24ccd8 100644 --- a/src/util/virhostdev.c +++ b/src/util/virhostdev.c @@ -1590,18 +1590,35 @@ virHostdevPCINodeDeviceReAttach(virHostdevManagerPtr hostdev_mgr, virPCIDevicePtr pci) { virPCIDeviceAddressPtr devAddr = NULL; + bool usesVfio = false; + char *drvPath = NULL; + char *drvName = NULL; struct virHostdevIsPCINodeDeviceUsedData data = {hostdev_mgr, NULL, false}; int ret = -1; + if (virPCIDeviceGetDriverPathAndName(pci, &drvPath, &drvName) < 0) + goto out; + + if (STREQ_NULLABLE(drvName, "vfio-pci")) + usesVfio = true; + virObjectLock(hostdev_mgr->activePCIHostdevs); virObjectLock(hostdev_mgr->inactivePCIHostdevs); if (!(devAddr = virPCIDeviceGetAddress(pci))) goto out; - if (virHostdevIsPCINodeDeviceUsed(devAddr, &data)) + if (usesVfio) { + /* Doesn't matter which device. If any domain is actively using the + * iommu group, refuse to reattach */

+ if (virPCIDeviceAddressIOMMUGroupIterate(devAddr, + virHostdevIsPCINodeDeviceUsed, + &data) < 0) + goto out; + } else if (virHostdevIsPCINodeDeviceUsed(devAddr, &data)) { goto out; + } virPCIDeviceReattachInit(pci); @@ -1614,6 +1631,8 @@ virHostdevPCINodeDeviceReAttach(virHostdevManagerPtr hostdev_mgr, virObjectUnlock(hostdev_mgr->inactivePCIHostdevs); virObjectUnlock(hostdev_mgr->activePCIHostdevs); VIR_FREE(devAddr); + VIR_FREE(drvPath); + VIR_FREE(drvName); return ret; }