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gdb error: Backtrace stopped: previous frame identical to this frame (corrupt stack?)

I am having problems debugging a multi-threaded C++ application on an ARMv7 targets. The issue shows up on two different ARM targets, and I use different toolchains for them:

Backtrace stopped: previous frame identical to this frame (corrupt stack?)

I've checked some threads, but (due to having the same issue with a minimalistic multithreading program) it seems that I * don't have a corrupted stack * any issues with virtual functions or function pointers

Mostly I'm using the target Toradex Colibri iMX6 which has an Angstrom Linux 2016.12 running on it.

Questions

  • Is there something wrong with how I build the program?
  • is there sth. wrong with how I'm using the gdbserver / gdb?
  • which options do I have to fix the debugger output?

I debug via gdbserver on the target and the toolchain's arm-linux-gnueabihf-gdb on my host. There's no native gdb for any of the targets. I can build the application for Linux x86, but can't reproduce the bug so far on the PC.

SW-problem

It seems that two of the threads are getting stuck, maybe due to a deadlock of two mutexes, or a thread trying to get one mutex a second time (although that seems unlikely, the bug showed up after I've configured a mutex as recursive; I'll have to check for a second mutex used in that thread).

All other threads seem to keep running fine.

SW-build and debug configuration

Build settings:

I'm using a toolchain provided by Toradex with arm-linux-gnueabihf-g++ and

-std=c++11 -Wall -Werror -Wextra -Wno-unused-result -Winit-self -Wmissing-include-dirs -Wpointer-arith -Wno-format-security -Wno-implicit-fallthrough -Wl,-Map=output.map -ggdb -g3 -fno-inline -O0

I pass the same program to the debuggers (i.e. to gdbserver on the target and to arm-linux-gnueabihf-gdb on the host)

$ (gdb) set sysroot </path/to/libs>
$ (gdb) file <binary>
$ (gdb) target remote IP:port

shared libraries:

For shared libraries, I've copied the /usr/lib and /lib from the target to the host. I've then downloaded the debug libraries which are available for the target/distribution and replaced the original shared libs with those.

(gdb) info sharedlibrary
From        To          Syms Read   Shared Object Library
0x76fcf800  0x76feaa70  Yes         /path/to/libs/lib/ld-linux-armhf.so.3
0x76fb9700  0x76fbcd2c  Yes         /path/to/libs/lib/librt.so.1
0x76f940c0  0x76fa2e0c  Yes         /path/to/libs/lib/libpthread.so.0
0x76f01630  0x76f72a10  Yes (*)     /path/to/libs/usr/lib/libstdc++.so.6
0x76e14d38  0x76e48028  Yes         /path/to/libs/lib/libm.so.6
0x76e041b0  0x76e0e7ec  Yes         /path/to/libs/lib/libgcc_s.so.1
0x76cd1000  0x76dc2b10  Yes         /path/to/libs/lib/libc.so.6
0x7449c96c  0x744a29e4  Yes         /path/to/libs/lib/libnss_files.so.2
(*): Shared library is missing debugging information.

I could not find a debug library for libstdc++.so.6.

Debugging results

Debug simple single-threaded application with crash on target:

  • works, i.e. does not report the error message from above

Debug simple multi-threaded application, with or without deadlock, on target:

(gdb) bt
#0  0x76d6cd44 in uname () at ../sysdeps/unix/syscall-template.S:84
#1  0x00000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Debug the same simple multi-threaded application, with or without deadlock, on Linux-x86:

  • works

Debug buggy application on PC:

  • seems to work, but we cannot reproduce the bug so far

Debug the affected application on target:

Thread 1 received signal SIGINT, Interrupt.
0x76f9facc in __lll_robust_lock_wait (futex=0x257b94 <namespace1::function()::su_place+20>, private=0)
at /usr/src/debug/glibc/2.24-r0/git/nptl/lowlevelrobustlock.c:46
46    /usr/src/debug/glibc/2.24-r0/git/nptl/lowlevelrobustlock.c: No such file or directory.
(gdb) thread apply all bt

Thread 6 (Thread 6606.6630):
#0  0x76d832c8 in __setreuid (ruid=8, euid=0)
at /usr/src/debug/glibc/2.24-r0/git/sysdeps/unix/sysv/linux/i386/setreuid.c:29
#1  0x7efff06c in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 5 (Thread 6606.6629):
#0  0x76d55d44 in uname () at ../sysdeps/unix/syscall-template.S:84
#1  0x00000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 4 (Thread 6606.6628):
#0  0x76d55d44 in uname () at ../sysdeps/unix/syscall-template.S:84
#1  0x00000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 3 (Thread 6606.6627):
#0  0x76d55d44 in uname () at ../sysdeps/unix/syscall-template.S:84
#1  0x00000000 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 2 (Thread 6606.6626):
#0  __lll_robust_lock_wait (
futex=0x25b950 <namespace_2::a_function()::a_static_member+152>, private=128)
at /usr/src/debug/glibc/2.24-r0/git/nptl/lowlevelrobustlock.c:31
#1  0x00000080 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 1 (Thread 6606.6606):
#0  0x76f9facc in __lll_robust_lock_wait (futex=0x257b94 <namespace1::function()::su_place+20>, 
private=0) at /usr/src/debug/glibc/2.24-r0/git/nptl/lowlevelrobustlock.c:46
#1  0x00000002 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Update

I could find the bug (mutex deadlock) using valgrind with the PC-build of the SW.

However, the issue here is about the problems with gdb, which I could not understand or solve yet.

like image 476
radix Avatar asked Oct 16 '22 11:10

radix


1 Answers

I've then downloaded the debug libraries which are available for the target/distribution and replaced the original shared libs with those.

This is possibly the wrong thing to do (depending on what exactly you mean by "debug libraries"), and may be contributing to your problem. See this answer.

As a first step, I would use the exact same libraries that you are using on the target, and check whether that changes the behavior of GDB.

like image 130
Employed Russian Avatar answered Oct 21 '22 03:10

Employed Russian