Re: sendmail function probe registration error with systemtap

[fche@redhat.com (Frank Ch. Eigler)]

Xiaokui Shu <subbyte@gmail.com> writes:

> [...] I start systemtap with a simple probe
> (shown below), I get two warnings in Pass 5. While running systemtap,
> [...]
> WARNING: probe process("/usr/sbin/sendmail.sendmail").function("mime_getchar_crlf.part.1")
> inode-offset 0005e620 registration error (rc -524)
> WARNING: probe process("/usr/sbin/sendmail.sendmail").function("frame_dummy")
> inode-offset 0001cc80 registration error (rc -524)

That's -ENOTSUPP; maybe there is some sort of instruction in there the
kernel doesn't like.

> I can send emails to the monitored host, but my mailbox on the host
> does not receive them. [...]  Can anyone help me to figure out what
> is the problem brought by the tracing?

This sounds should not happen.

> probe process(@1).function("*")
> {
>     printf ("%s:0x%x\n", probefunc (), ustack (1))
> }

You might try rerunning '# stap -DSTP_ALIBI foo.stp' to eliminate most
of the systemtap probe handler logic out of the script.  If the
userspace sendmail process still misbehaves, this helps incriminate
uprobes -- and vice versa.

Could you collect kernel / stap version information, or the whole
`stap-report` shebang?


- FChE