Mainline BPF selftests failure due to rcu_tasks_trace and do_filp_open changes

Mainline BPF selftests failure due to rcu_tasks_trace and do_filp_open changes

[Shung-Hsi Yu]

Testing with Linus' tree (4adc13ed7c28), BPF selftests in failing in the
following cases across test_progs{,-no_alu32,-cpuv4}:

1. map_kptr: failed to create kprobe 'rcu_tasks_trace_postgp+0x0'

   rcu_tasks_trace_postgp() no longer exists with commit c27cea4416a3
   ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")[2]

2. test_profiler: failed to create kretprobe 'do_filp_open+0x0'

   renamed to do_file_open() in commit 541003b576c3 ("rename
   do_filp_open() to do_file_open()")[3]

Not familiar with when fix for these are usually done/sent. I suppose
after 7.0-rc1?

1: https://github.com/shunghsiyu/libbpf/actions/runs/21850240572/job/63055018509
2: https://lore.kernel.org/all/b206b083-f611-43b6-993f-78ddbe315813@paulmck-laptop/
3: https://lore.kernel.org/all/20260114043310.3885463-32-viro@zeniv.linux.org.uk/

Re: Mainline BPF selftests failure due to rcu_tasks_trace and do_filp_open changes

[Alexei Starovoitov]

On Mon, Feb 9, 2026 at 11:34 PM Shung-Hsi Yu <shung-hsi.yu@suse.com> wrote:
>
> Testing with Linus' tree (4adc13ed7c28), BPF selftests in failing in the
> following cases across test_progs{,-no_alu32,-cpuv4}:
>
> 1. map_kptr: failed to create kprobe 'rcu_tasks_trace_postgp+0x0'
>
>    rcu_tasks_trace_postgp() no longer exists with commit c27cea4416a3
>    ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")[2]
>
> 2. test_profiler: failed to create kretprobe 'do_filp_open+0x0'
>
>    renamed to do_file_open() in commit 541003b576c3 ("rename
>    do_filp_open() to do_file_open()")[3]
>
> Not familiar with when fix for these are usually done/sent. I suppose
> after 7.0-rc1?

These failures are typical for every merge window.
Since you've discovered them first please send the fixes :)
Targeting bpf tree...

Re: Mainline BPF selftests failure due to rcu_tasks_trace and do_filp_open changes

[Ihor Solodrai]

On 2/9/26 11:34 PM, Shung-Hsi Yu wrote:
> Testing with Linus' tree (4adc13ed7c28), BPF selftests in failing in the
> following cases across test_progs{,-no_alu32,-cpuv4}:
> 
> 1. map_kptr: failed to create kprobe 'rcu_tasks_trace_postgp+0x0'
> 
>    rcu_tasks_trace_postgp() no longer exists with commit c27cea4416a3
>    ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")[2]
> 
> 2. test_profiler: failed to create kretprobe 'do_filp_open+0x0'
> 
>    renamed to do_file_open() in commit 541003b576c3 ("rename
>    do_filp_open() to do_file_open()")[3]
> 

Hi Shung-Hsi,

I've just sent out a fix for test_profiler [1].

As for map_kptr, I disabled it temporarily on BPF CI.  I looked into
this a little, and the test relies on kprobing a static function,
which isn't very reliable.  Kumar has some ideas how to make the test
better, stay tuned.

[1] https://lore.kernel.org/bpf/20260210235855.215679-1-ihor.solodrai@linux.dev/

> Not familiar with when fix for these are usually done/sent. I suppose
> after 7.0-rc1?

AFAIU yes, the patches fixing this would go through -rc PRs.

> 
> 1: https://github.com/shunghsiyu/libbpf/actions/runs/21850240572/job/63055018509
> 2: https://lore.kernel.org/all/b206b083-f611-43b6-993f-78ddbe315813@paulmck-laptop/
> 3: https://lore.kernel.org/all/20260114043310.3885463-32-viro@zeniv.linux.org.uk/

Re: Mainline BPF selftests failure due to rcu_tasks_trace and do_filp_open changes

[Shung-Hsi Yu]

On Tue, Feb 10, 2026 at 01:00:40PM -0800, Alexei Starovoitov wrote:
> On Mon, Feb 9, 2026 at 11:34 PM Shung-Hsi Yu <shung-hsi.yu@suse.com> wrote:
> >
> > Testing with Linus' tree (4adc13ed7c28), BPF selftests in failing in the
> > following cases across test_progs{,-no_alu32,-cpuv4}:
> >
> > 1. map_kptr: failed to create kprobe 'rcu_tasks_trace_postgp+0x0'
> >
> >    rcu_tasks_trace_postgp() no longer exists with commit c27cea4416a3
> >    ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")[2]
> >
> > 2. test_profiler: failed to create kretprobe 'do_filp_open+0x0'
> >
> >    renamed to do_file_open() in commit 541003b576c3 ("rename
> >    do_filp_open() to do_file_open()")[3]
> >
> > Not familiar with when fix for these are usually done/sent. I suppose
> > after 7.0-rc1?
> 
> These failures are typical for every merge window.
> Since you've discovered them first please send the fixes :)
> Targeting bpf tree...

I overthink it and thought I'll need to wait until rc1 tagged. Glad
target bpf tree is all that's needed. Will try to do so next time :)

Thanks!

Re: Mainline BPF selftests failure due to rcu_tasks_trace and do_filp_open changes

[Shung-Hsi Yu]

On Tue, Feb 10, 2026 at 04:08:22PM -0800, Ihor Solodrai wrote:
> On 2/9/26 11:34 PM, Shung-Hsi Yu wrote:
> > Testing with Linus' tree (4adc13ed7c28), BPF selftests in failing in the
> > following cases across test_progs{,-no_alu32,-cpuv4}:
> > 
> > 1. map_kptr: failed to create kprobe 'rcu_tasks_trace_postgp+0x0'
> > 
> >    rcu_tasks_trace_postgp() no longer exists with commit c27cea4416a3
> >    ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")[2]
> > 
> > 2. test_profiler: failed to create kretprobe 'do_filp_open+0x0'
> > 
> >    renamed to do_file_open() in commit 541003b576c3 ("rename
> >    do_filp_open() to do_file_open()")[3]
> > 
> 
> Hi Shung-Hsi,
> 
> I've just sent out a fix for test_profiler [1].
> 
> As for map_kptr, I disabled it temporarily on BPF CI.  I looked into
> this a little, and the test relies on kprobing a static function,
> which isn't very reliable.  Kumar has some ideas how to make the test
> better, stay tuned.

Saw it merged today, thanks for the pointer!

> [1] https://lore.kernel.org/bpf/20260210235855.215679-1-ihor.solodrai@linux.dev/
> 
> > Not familiar with when fix for these are usually done/sent. I suppose
> > after 7.0-rc1?
> 
> AFAIU yes, the patches fixing this would go through -rc PRs.
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