[Bug]: bpftrace cannot obtain ena_io_poll return value about amzn-drivers HOT 5 CLOSED

Hi @Data-crea

Thanks for submitting the query, the command you've posted works well on Amazon Linux 2 and Ubuntu 22.04.
We will investigate to see why it doesn't work on Amazon Linux 2023 and will get back to you.
Stay tuned.

from amzn-drivers.

Hi @Data-crea,
We can confirm that this issue has been replicated in the Amazon Linux 2023 kernel (version 6.1).
Although the problem is not related to the ENA driver, we have internally assigned it to the Amazon Linux kernel team.

To mitigate this issue, you can:

1. Use Amazon Linux 2 (5.10)
2. Use kretfunc

sudo bpftrace -e 'kretfunc:ena:ena_io_poll {@[nsecs/1000000000]=count();}'

We will provide an update once we receive a resolution from the Amazon Linux team.

Thank you for bringing this to our attention.

from amzn-drivers.

Hi @amitbern-aws @davidarinzon

Hi @Data-crea, We can confirm that this issue has been replicated in the Amazon Linux 2023 kernel (version 6.1). Although the problem is not related to the ENA driver, we have internally assigned it to the Amazon Linux kernel team.

To mitigate this issue, you can:

1. Use Amazon Linux 2 (5.10)
2. Use kretfunc

sudo bpftrace -e 'kretfunc:ena:ena_io_poll {@[nsecs/1000000000]=count();}'

Thank you very much for your effective response! I will try this!

We will provide an update once we receive a resolution from the Amazon Linux team.

Thank you for bringing this to our attention.

from amzn-drivers.

Update from kernel team:

• The bug introduced in commit ("tracing/kprobes: Return EADDRNOTAVAIL when func matches several symbols") merged in upstream kernel v6.1.60 and broke the kprobe on kernel module symbols.
• The fix ("tracing/kprobes: Fix symbol counting logic by looking at modules as well") will be merged to v6.1.71.

Amazon Linux 2023 will take the fix in the coming weeks,
Will update once its available.

Thanks

from amzn-drivers.

I see it! Thanks again!

from amzn-drivers.