The real issue isn't the warning, but the error:

semantic error: process return probes not available [man error::inode-uprobes]

Hopefully the information given is useful.
Try: man error::inode-uprobes
Which should give you:
https://manpages.ubuntu.com/manpages/impish/man7/error::inode-uprobes.7stap.html

Hi, Mark Wielaard 

thanks for your response.

I try to change the suggest and remove *.return because Ubuntu 18.04 kernel version is 5.4.0

```
-probe process("/usr/bin/bash").function("*_builtin").return {
+probe process("/bin/bash").function("*_builtin") {
    if (in_call_tree(pid(), DONLY) == 1) {
        if(@defined($list)){
            printf("%s %d = %s(%s)\n", logstamp(0), $return, ppfunc(), bash_builtin_arg[ppfunc()])
                delete bash_builtin_arg[ppfunc()]
        }
    }
}
```

But I still encounter some error.

# stap -p4 -r $(uname -r) tracer.stp -m tracer -v -g --suppress-time-limits
WARNING: Probe 'process' has been elided: keyword at :1294:1
 source: probe process("/bin/bash").function("*_builtin") {
         ^
semantic error: while processing probe tp_syscall.open.return from: nd_syscall.open.return from: syscall.open.return from: syscall.open.return

semantic error: internal error: @entry is only valid in .return probes: operator '@entry' at :652:32
        source:         filename = user_string(@entry($filename), err_msg)
                                               ^

May I have misunderstood your tip?

Hi Mark Wielaard:

If I want to use "process.statement()" replace "process.function().return"
-probe process("/usr/bin/bash").function("*_builtin").return

Would you give me some feedback?

I must say I don't really understand some of the issues you are seeing. But it looks like you are using a couple of years old Ubuntu install. Maybe you can ask them if they are still supporting that and can help you with using these more modern systemtap features.

> # stap -p4 -r $(uname -r) tracer.stp -m tracer -v -g --suppress-time-limits
> WARNING: Probe 'process' has been elided: keyword at :1294:1
>  source: probe process("/bin/bash").function("*_builtin") {
>          ^

This is weird, it means stap believes this probe is empty. But what you show above looks like it isn't. Do all if statements evaluate to false?

> semantic error: while processing probe tp_syscall.open.return from: nd_syscall.open.return from: syscall.open.return from: syscall.open.return
> 
> semantic error: internal error: @entry is only valid in .return probes: operator '@entry' at :652:32
>         source:         filename = user_string(@entry($filename), err_msg)
>                                                ^

This is even more curious. This seems to have nothing to do with the script you posted. I cannot explain why the above expands to something that uses an @entry.

Might there be more to the script than what you posted in this bug?

Hi Mark Wielaard,

thanks for your help

When I use process.statement() or process.function replace  process.function().return 

I can fix "error::inode-uprobes" issue

but my stap has other error
"semantic error: while processing probe tp_syscall.read.return from: nd_syscall.read.return from: syscall.read.return from: syscall.read.return"

I try to reduce this stap script

```
...

probe syscall.write { write_fds[tid()] = fd }

probe syscall.write.return {
  p = pid()
  // Get fd even if non-dwarf syscall return probe.
  fd = write_fds[tid()]
  delete write_fds[tid()]
  bytes = retval
  time = gettimeofday_us() - @entry(gettimeofday_us())
  if (bytes > 0)
    filewrite[p, fd] <<< bytes
  time_io[p, fd] <<< time
}

...
```

the error message point out the problem is "syscall.xxx.return"

I try to comment (/**/) it, and the compiler's result is ok

I just curious about this result.

(In reply to Nylon Chen from comment #5)
> but my stap has other error
> "semantic error: while processing probe tp_syscall.read.return from:
> nd_syscall.read.return from: syscall.read.return from: syscall.read.return"

Right, but that seems a totally other issue than you originally reported.
If you were using syscall probes then you really should have added that to the original report. I suspect other issues you are seeing might also come from not providing the full script you are using.

Might I again suggest you upgrade your system to something more modern and/or contact Ubuntu support about the kernel/systemtap combination they are shipping to make sure they are compatible.
 
> I try to reduce this stap script
> 
> ```
> ...
> 
> probe syscall.write { write_fds[tid()] = fd }
> 
> probe syscall.write.return {
>   p = pid()
>   // Get fd even if non-dwarf syscall return probe.
>   fd = write_fds[tid()]
>   delete write_fds[tid()]
>   bytes = retval
>   time = gettimeofday_us() - @entry(gettimeofday_us())
>   if (bytes > 0)
>     filewrite[p, fd] <<< bytes
>   time_io[p, fd] <<< time
> }
> 
> ...
> ```
> 
> the error message point out the problem is "syscall.xxx.return"
> 
> I try to comment (/**/) it, and the compiler's result is ok
> 
> I just curious about this result.

Right, since your systemtap/kernel doesn't support return probes you cannot use @entry in your script. Since you already have an syscall entry probe I suggest to record the time in the same way you record the write_fds.