Bug 1598780
| Summary: | memballoon will not work when enable iommu | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux Advanced Virtualization | Reporter: | yalzhang <yalzhang> |
| Component: | libvirt | Assignee: | Virtualization Maintenance <virt-maint> |
| Status: | CLOSED DEFERRED | QA Contact: | Jing Qi <jinqi> |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 8.0 | CC: | dyuan, jinqi, lhuang, lmen, rbalakri, xuzhang |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2020-02-18 14:23:08 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
This bug was closed deferred as a result of bug triage. Please reopen if you disagree and provide justification why this bug should get enough priority. Most important would be information about impact on customer or layered product. Please indicate requested target release. |
Description of problem: memballoon will not work when enable iommu Version-Release number of selected component (if applicable): libvirt-4.5.0-1.el7.x86_64 qemu-kvm-rhev-2.12.0-7.el7.x86_64 How reproducible: 100% Steps to Reproduce: 1. prepare host support VT-d, add "intel_iommu=on" to kernel line 2. Prepare a q35 guest and add the xml as below in the guest .... <memory unit='KiB'>2097152</memory> <currentMemory unit='KiB'>2097152</currentMemory> ..... <features> <ioapic driver='qemu'/> ... </features> ... <iommu model='intel'> <driver intremap='on' iotlb='on'/> </iommu> <memballoon model='virtio'> <address type='pci' domain='0x0000' bus='0x06' slot='0x00' function='0x0'/> <driver iommu='on' ats='on'/> </memballoon> ... 3. Add "intel_iommu=on" to kernel line of q35 guest, then reboot the guest 4. check on guest for current memory size [on guest] # cat /proc/meminfo | grep MemTotal MemTotal: 1863840 kB 5. change the memory on host, then check, it do not work [on host] # virsh setmem rhelq 1048576 [on host] # virsh dumpxml rhelq | grep -i mem <memory unit='KiB'>2097152</memory> <currentMemory unit='KiB'>2097152</currentMemory> 6. check on guest, there is no change [on guest] # cat /proc/meminfo | grep MemTotal MemTotal: 1863840 kB Actual results: in step 5, 6, after setmem, the guest memory do not change Expected results: guest memory should be set correctly Additional info: destroy the guest, edit the xml to delete the "<driver iommu='on' ats='on'/>", start the guest and redo all the steps. 1. check before the test [on guest]# cat /proc/meminfo | grep MemTotal MemTotal: 1863840 kB [on host] # virsh dumpxml rhelq | grep -i mem <memory unit='KiB'>2097152</memory> <currentMemory unit='KiB'>2097152</currentMemory> 2. change the memory size for guest, then check it works [on host] # virsh setmem rhelq 1048576 [on host] # virsh dumpxml rhelq | grep -i Mem <memory unit='KiB'>2097152</memory> <currentMemory unit='KiB'>1048576</currentMemory> 3. check on guest, it works [on guest] # cat /proc/meminfo | grep MemTotal MemTotal: 815264 kB