[linux-azure][hibernation] Mellanox CX4 NIC's TX/RX packets stop increasing after hibernation/resume
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux-azure (Ubuntu) |
Invalid
|
Undecided
|
Unassigned | ||
Focal |
Fix Released
|
Medium
|
Marcelo Cerri |
Bug Description
[Impact]
Description of problem:
In a VM with CX4 VF NIC on Azure, after hibernation/resume, the TX/RX packet counters stop increaseing.
This issue doesn't exist in VM with a CX3 VF NIC.
This happens to the latest stable release of the linux-azure 5.4.0-1023.23 kernel and the latest mainline linux kernel.
[Test Case]
How reproducible:
100%
Steps to Reproduce:
1. Start a VM in Azure that supports Accelerated Networking, and enable hibernation properly (please refer to https:/
2. Do hibernation from serial console
# systemctl hibernate
3. After the VM resumes back, check the MSI interrupt counters in /proc/interrupts for the CX-4 NIC, and also check “ifconfig” (e.g. “ifconfig enP2642s2”) for the RX/TX counters. These counters stop increasing while they should.
[Regression Potential]
The change touches netvsc and has potential to affect any instances using accelerated networking. However the fix is straightforward and it's a clean cherry-pick from 5.9.
[Other Info]
BUG FIX:
The fix is in the net.git tree now:
https:/
CVE References
Changed in linux-azure (Ubuntu Focal): | |
assignee: | nobody → Marcelo Cerri (mhcerri) |
Changed in linux-azure (Ubuntu): | |
status: | New → Invalid |
Changed in linux-azure (Ubuntu Focal): | |
importance: | Undecided → Medium |
Changed in linux-azure (Ubuntu Focal): | |
status: | In Progress → Fix Committed |
We also need the second and the third patch:
https:/ /git.kernel. org/pub/ scm/linux/ kernel/ git/netdev/ net.git/ commit/ ?id=de214e52de1 bba5392b5b70549 24a08dbd57c2f6
https:/ /git.kernel. org/pub/ scm/linux/ kernel/ git/netdev/ net.git/ commit/ ?id=da26658c3d7 005aa67a706dcef f7b2807b59e123