pax driver failed to load (intel vtune profiler 2020, update 2, ubuntu 20.04)

[jolars]

I am getting the following error message when trying to install intel vtune profiler 2020, update 2:

Warning:  the following driver(s) were not found loaded in the kernel:  sep5.

Checking for PMU arbitration service (PAX) ... not detected.
Attempting to start PAX service ...
Executing: insmod ./pax/pax-x32_64-5.4.0-42-genericsmp.ko
insmod: ERROR: could not insert module ./pax/pax-x32_64-5.4.0-42-genericsmp.ko: Operation not permitted

Error:  pax driver failed to load!

You may need to build pax driver for your kernel.
Please see the pax driver README for instructions.


Error: failed to start or connect to required PAX service

Everything else in the installation seems to have worked properly. If I try to repair the installation or install the drivers separately, I run into the same issue.

I am on a local install (not a virtual machine) of ubuntu 20.04, kernel 5.4.0-42-generic (which seems to match the driver).

I have checked the prerequisites in the PAX readme file and everything seems to be set up properly.

[Kirill_U_Intel]

Hi.

Could you share dmesg info after calling insmod-sep script?

Thanks, Kirill

[Kirill_U_Intel]

I mean dmesg log like this one

kuhanov@localhost:~/kuhanov# dmesg
[26125.796955] PAX: PMU arbitration service v1.0.2 has been started.
[26127.129954] socperf3_0: SocPerf Driver loading...
[26127.129956] socperf3_0: SocPerf Driver about to register chrdev...
[26127.129958] socperf3_0: SocPerf Driver: result of alloc_chrdev_region is 0
[26127.129959] socperf3_0: SocPerf Driver: major number is 234
[26127.129963] socperf3_0: SocPerf Driver: detected 96 CPUs in lwpmudrv_Load
[26127.129964] socperf3_0: SocPerf Driver: creating device socperf3!c...
[26127.130069] socperf3_0: PMU check enabled! F6.M55.S7 index=-1
[26127.130070] socperf3_0: No MMIO list information detected!
[26127.130072] socperf3_0: SocPerf Driver v3.0.0 has been loaded.
[26128.146089] sep5_20: Driver loading...
[26128.147756] sep5_20: [load] [UTILITY_Driver_Log_Init@1011]: Initialized driver log using contiguous physical memory.
[26128.147763] sep5_20: [load] [lwpmu_Load@6557]: Major number is 511
[26128.147774] sep5_20: [load] [lwpmu_Load@6564]: Detected 96 total CPUs and 96 active CPUs.
[26128.196196] sep5_20: [load] [lwpmu_Load@6859]: PMU collection driver v5.20.6 Beta has been loaded.
[26128.196201] sep5_20: [load] [lwpmu_Load@6869]: NMI will be used for handling PMU interrupts.
[26128.196209] sep5_20: [load] [PMU_LIST_Initialize@654]: PMU check enabled! F6.M55.S7 index=7 drv_type=PUBLIC

[26129.263512] vtsspp: Driver version 1.8.229-611328
[26129.266501] vtsspp: Kernel version 5.4.0-31-generic
[26129.266506] vtsspp: Detected 96 CPUs
[26129.266509] vtsspp: CPU family: 0x06, model: 0x55, stepping: 07, HT: yes
[26129.266510] vtsspp: CPU freq: 2095077KHz, timer freq: 1000000KHz
[26129.266518] vtsspp: PMU: fixed counters: 3, general counters: 4
[26129.269084] vtsspp: KPTI is enabled
[26129.269085] vtsspp: KASLR is detected
[26129.269087] vtsspp: Driver has been loaded
[26129.291553] -----------------------------------------
[26129.291555] OK: LOADED SoC Watch Driver

[jolars]

Thanks; I get

[10705.376420] Lockdown: insmod: unsigned module loading is restricted; see man kernel_lockdown.7

[jolars]

Could this be related to UEFI secure boot (which I have enabled)?

[Kirill_U_Intel]

I suppose yes.

could you try this one?

To get the module loading, disable kernel lockdown via sys-rq:

# echo 1 > /proc/sys/kernel/sysrq
# echo x > /proc/sysrq-trigger

from

https://unix.stackexchange.com/questions/543576/modprobe-fails-with-operation-not-permitted

[jolars]

I just did, actually, but to no avail.

Another post (https://forums.centos.org/viewtopic.php?t=47224) recommended checking if CONFIG_MODULE_SIG_FORCE is enabled at compile-time, or if enforcemodulesig=1 is enabled at boot, but they are not.

cat /boot/config-`uname -r` | grep CONFIG_MODULE_SIG_FORCE
# CONFIG_MODULE_SIG_FORCE is not set

Is there any particular reason for why the driver is not signed? I am not thrilled about the prospect of disabling secure boot.

[Kirill_U_Intel]

I think it is not possible on general system.

we must have signing keys.

you could sign them if you build kernel yourself.

Kirill

[ChithraJ_Intel]

Hi,

Has the solution provided by Kirill worked for you. Please let us know if the issue still persists.

Regards,

Chithra

[Kirill_U_Intel]

Also VTune allows to run driverless hardware collections based on the perf. Probably you could skip building/installing vtune drivers at all and get the useful profile.

Kirill

[jolars]

Well, turning off secure boot does solve the problem, even if it's not really solving my problem.

The driverless option works too, but I prefer to use the drivers.

[ChithraJ_Intel · Accepted solution]

Hi Johan,

Thanks for your update.

Pax driver is actually part of SEP. VTune drivers are unsigned and a secure boot requires cryptographically signed drivers to be used. As of now this is not supported by vtune. As a fall back , you can make use of perf if SEP is not available.

Since your issue is resolved by turning off secure boot, shall we discontinue monitoring this thread?

Regards,

Chithra

[ChithraJ_Intel]

Hi Johan,

Thanks for the confirmation. We would discontinue monitoring this issue.Please raise a new thread if you have further issues.

Regards,

Chithra