Running testpmd as non-root user with uio_pci_generic

Running testpmd as non-root user with uio_pci_generic

[Isaac Boukris]

Hi,

I tried to run testpmd as a non-root user with uio_pci_generic (i.e.
not vfio-pci) on a vmxnet3 interface by setting the
'cap_ipc_lock,cap_sys_admin' capabilities as according to the doc at:
https://doc.dpdk.org/guides-21.11/linux_gsg/enable_func.html

But that didn't work and I was still getting the documented error:
EAL: rte_mem_virt2phy(): cannot open /proc/self/pagemap: Permission denied

I dug a little and found that I had to add the 'cap_dac_override' as
well and then it worked, the hint was at (which also includes a small
demo program): https://bugs.centos.org/view.php?id=17176

I thought it was worth sharing as I have seen it being asked a couple of times.

Cheers,
Isaac

Re: Running testpmd as non-root user with uio_pci_generic

[Thomas Monjalon]

14/01/2023 23:17, Isaac Boukris:
> Hi,
> 
> I tried to run testpmd as a non-root user with uio_pci_generic (i.e.
> not vfio-pci) on a vmxnet3 interface by setting the
> 'cap_ipc_lock,cap_sys_admin' capabilities as according to the doc at:
> https://doc.dpdk.org/guides-21.11/linux_gsg/enable_func.html
> 
> But that didn't work and I was still getting the documented error:
> EAL: rte_mem_virt2phy(): cannot open /proc/self/pagemap: Permission denied
> 
> I dug a little and found that I had to add the 'cap_dac_override' as
> well and then it worked, the hint was at (which also includes a small
> demo program): https://bugs.centos.org/view.php?id=17176
> 
> I thought it was worth sharing as I have seen it being asked a couple of times.

Thank you for reporting.

The preferred solution is to use the capability DAC_READ_SEARCH.

The DPDK doc is updated:
https://git.dpdk.org/dpdk/commit/?id=50b567c66da268bcc
(so you become a DPDK contributor :)