CentOS 6.9 (kernel-2.6.32-696.30.1.el6.x86_64) / depmod issue

[johanburati]

I've installed LIS 4.2.5-2 from https://aka.ms/lis on a CentOS 6.9 VM (OpenLogic:CentOS:6.9:latest)

[root@c69l LISISO]# cat /etc/centos-release
CentOS release 6.9 (Final)
[root@c69l LISISO]# uname -r
2.6.32-696.30.1.el6.x86_64
[root@c69l ~]# tar xzf /tmp/lis-rpms-4.2.5-2.tar.gz 
[root@c69l ~]# cd LISISO
[root@c69l LISISO]# ./install.sh 
Removing Hyper-V daemons
Invoking release specific install file in directory CentOS69
Installing the Linux Integration Services for Microsoft Hyper-V...
Preparing...                ########################################### [100%]
   1:kmod-microsoft-hyper-v ########################################### [100%]
Preparing...                ########################################### [100%]
   1:microsoft-hyper-v-debug########################################### [ 50%]
   2:microsoft-hyper-v      ########################################### [100%]
Saving old initramfs
Installing new initramfs
Adding KVP Daemon to Chkconfig....
Starting KVP Daemon....
Adding VSS Daemon to Chkconfig....
Starting VSS Daemon....
Adding FCOPY Daemon to Chkconfig....
Starting FCOPY Daemon....
 Linux Integration Services for Hyper-V has been installed. Please reboot your system.
[root@c69l LISISO]# reboot

Verified that the driver version was 4.2.5-2:

[root@c69l ~]# modinfo hv_vmbus
filename:       /lib/modules/2.6.32-696.30.1.el6.x86_64/weak-updates/microsoft-hyper-v/hv_vmbus.ko
version:        4.2.5.2
license:        GPL
srcversion:     563CE3C50B61BCDE6A452A0
alias:          acpi*:VMBus:*
alias:          acpi*:VMBUS:*
depends:        

After I ran depmod -a, the drivers point back to the built-in ones:

[root@c69l ~]# depmod -a
[root@c69l ~]# modinfo hv_vmbus
filename:       /lib/modules/2.6.32-696.30.1.el6.x86_64/kernel/drivers/hv/hv_vmbus.ko
version:        3.1
license:        GPL
retpoline:      Y
srcversion:     A280F9C354AF9451F98BE62
alias:          acpi*:VMBus:*
alias:          acpi*:VMBUS:*
depends:        
vermagic:       2.6.32-696.30.1.el6.x86_64 SMP mod_unload modversions 

If you reboot the VM you will lose network connectivity,
I had to connect to the serial console to run the commands:

[root@c69l ~]# ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
[root@c69l ~]# modprobe hv_netvsc
hv_netvsc: disagrees about version of symbol vmbus_driver_unregister
hv_netvsc: Unknown symbol vmbus_driver_unregister
hv_netvsc: disagrees about version of symbol vmbus_sendpacket
hv_netvsc: Unknown symbol vmbus_sendpacket
hv_netvsc: disagrees about version of symbol vmbus_teardown_gpadl
hv_netvsc: Unknown symbol vmbus_teardown_gpadl
hv_netvsc: disagrees about version of symbol vmbus_close
hv_netvsc: Unknown symbol vmbus_close
hv_netvsc: disagrees about version of symbol vmbus_recvpacket_raw
hv_netvsc: Unknown symbol vmbus_recvpacket_raw
hv_netvsc: disagrees about version of symbol vmbus_open
hv_netvsc: Unknown symbol vmbus_open
hv_netvsc: disagrees about version of symbol vmbus_set_sc_create_callback
hv_netvsc: Unknown symbol vmbus_set_sc_create_callback
hv_netvsc: disagrees about version of symbol __vmbus_driver_register
hv_netvsc: Unknown symbol __vmbus_driver_register
hv_netvsc: disagrees about version of symbol vmbus_establish_gpadl
hv_netvsc: Unknown symbol vmbus_establish_gpadl
hv_netvsc: disagrees about version of symbol vmbus_sendpacket_pagebuffer
hv_netvsc: Unknown symbol vmbus_sendpacket_pagebuffer
FATAL: Error inserting hv_netvsc (/lib/modules/2.6.32-696.30.1.el6.x86_64/kernel/drivers/net/hyperv/hv_netvsc.ko): Unknown symbol in module, or unknown parameter (see dmesg)

You can fix the issue by creating a symlink to hyperv.conf and run depmod -a again:

[root@c69l ~]# ln -s /opt/files/hyperv.conf /etc/depmod.d/hyperv.conf
[root@c69l ~]# depmod -a
[root@c69l ~]# modprobe hv_netvsc
hv_vmbus: registering driver hv_netvsc
hv_netvsc 000d3af8-ee2b-000d-3af8-ee2b000d3af8: real num tx,rx queues:1, 1
[root@c69l ~]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
    link/ether 00:0d:3a:f8:ee:2b brd ff:ff:ff:ff:ff:ff
    inet6 fe80::20d:3aff:fef8:ee2b/64 scope link
       valid_lft forever preferred_lft forever

I've checked on Centos 7.5 and it still points to version is 4.2.5-2 after running depmod -a

We had customers affected by this issue. Would it be possible for you to fix the LIS package asap ?

[chvalean]

Hello @johanburati
To make sure I got the steps right - so with LIS 4.2.5-2 you do have network connectivity after install & reboot.
The problem appears when after that you run #depmod -a and reboot, which breaks at least hv_netvsc, is that right?

[dibaskar]

Hello @chvalean,

After upgrading to LIS 4.2.5-2 "modinfo hv_vmbus" is listing 4.2.5.2 version. But if we run depmod -a and then check version again using "modinfo hv_vmbus" it points to old 3.1 version.

We need to create symbolic link as ln -s /opt/files/hyperv.conf /etc/depmod.d/hyperv.conf to make the latest version persistent after running "depmod -a".

[johanburati]

Any progress on this ?

I just deployed a fresh CentOS 6.9 VM (OpenLogic:CentOS:6.9:latest) and installed the LIS driver and still having the same issue.

I think it is just a matter of removing the rm -rf /etc/depmod.d/hyperv.conf line in the microsoft-hyper-v-4.2.5.3-20180717.x86_64.rpm package install script (file LISISO/CentOS69/microsoft-hyper-v-4.2.5.3-20180717.x86_64.rpm in the in the lis-rpms-4.2.5-2.tar.gz archive).

[vyadavmsft]

Thanks i see the issue , we are discussing internally the best way to address this, since removing line

rm -rf /etc/depmod.d/hyperv.conf
has other effect related to kernel upgrade.

[johnsongeorge-w]

This issue is addressed in 4.3.2 version.