From: Florian Weimer <fweimer@redhat.com>
To: Jacob Kroon <jacob.kroon@gmail.com>
Cc: Jacob Kroon via Gdb <gdb@sourceware.org>
Subject: Re: Debugging ld.so in gdb
Date: Fri, 04 Feb 2022 18:04:16 +0100 [thread overview]
Message-ID: <87czk2o967.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <f73d7ef6-7d2b-47c4-db0f-968608abcdd9@gmail.com> (Jacob Kroon's message of "Fri, 4 Feb 2022 17:53:27 +0100")
* Jacob Kroon:
> I couldn't see that address anywhere in the output of "show files".
>
> But I did "full" recording, and found a place where just stepping a
> single instruction broke gdb interpreting the backtrace, if that is of
> any help. This is what I do:
>
> 1. goto instruction 225037
> 2. print backtrace (looks sane)
> 3. do "disas"
> 4. step one instruction with "stepi"
> 5. print backtrace (looks garbled)
> 6. do "disas"
Interesting. Can you figure out where *rpo points right before things
go wrong? If the debuginfo doesn't work, this should do it:
print (void *)$rax - 8
Maybe also look at map->l_name at this point, and further up the stack,
in dl_sort_maps, at maps and nmaps. It looks like we run off the end of
the array and write garbage to other areas of the process. 8-(
This must be caused by something unusual in the object dependencies.
Thanks,
Florian
next prev parent reply other threads:[~2022-02-04 17:04 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-04 13:45 Jacob Kroon
2022-02-04 13:58 ` Florian Weimer
2022-02-04 14:09 ` Jacob Kroon
2022-02-04 14:22 ` Florian Weimer
2022-02-04 14:27 ` Jacob Kroon
2022-02-04 16:09 ` Florian Weimer
2022-02-04 16:53 ` Jacob Kroon
2022-02-04 17:04 ` Florian Weimer [this message]
2022-02-04 17:11 ` Jacob Kroon
2022-02-04 17:15 ` Florian Weimer
2022-02-07 8:36 ` Jacob Kroon
2022-02-07 11:46 ` Jacob Kroon
2022-02-07 11:55 ` Florian Weimer
2022-02-07 12:15 ` Jacob Kroon
2022-02-07 12:27 ` Florian Weimer
2022-02-07 12:32 ` Jacob Kroon
2022-02-07 13:39 ` Jacob Kroon
2022-02-07 13:45 ` Jacob Kroon
2022-02-07 13:53 ` Adhemerval Zanella
2022-02-07 13:54 ` Jacob Kroon
2022-02-07 14:07 ` Florian Weimer
2022-02-07 16:28 ` Florian Weimer
2022-02-07 17:04 ` Jacob Kroon
2022-02-04 14:45 ` Jacob Kroon
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