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

On Sun, Jan 26, 2020, 17:24 Abhi Arora <[email protected]> wrote:

> I am having an application with 16 Thread in ARM board running Linux. My
> problem crashed (Segmentation Fault) and I got the core dump. I was
> analyzing it and found out I was getting "Backtrace stopped: previous frame
> identical to this frame (corrupt stack?)" message for each of the thread
> except the "main" thread.
>
> I have posted backtrace of "main", thread that caused SEGV FAULT and a
> thread which was working fine.
>
> 1. I want to know why this message is coming up? What does this mean?
>     One possibility is corrupt stack but what other times it can show up?
>                  Recursive function call?
> 2. I am not sure how to get more information from Thread 1. I want to know
> which function has called "curl_easy_perform". I want to get complete
> backtrace of Thread 1. I tried to "set $sp = " but looks like I can't
> modify the SP. I want someone to help with an article to unstack my Thread
> 1 further. Please advise.


You should try to install debug symbols for libcurl. GDB can't always
unwind stacks without symbols.

FWIW, the stack for thread 5 is complete despite the message (it has
start_thread in it).

Christian


> Thread 5 (LWP 3238):
> #0  __libc_do_syscall () at libc-do-syscall.S:48
> #1  0x76ab0b00 in __GI___select (nfds=6, readfds=readfds@entry=0x7563ac58,
> writefds=writefds@entry=0x0, exceptfds=exceptfds@entry=0x0,
> timeout=timeout@entry=0x7563ac38)
>     at /usr/src/debug/glibc/2.28-r0/git/sysdeps/unix/sysv/linux/select.c:41
> #2  0x004a2ace in Isom::Checksafetybuttons (this=this@entry=0x158f780) at
> /home/abhishek/develop/gateway-app/GatewayApp/source/WebServer/isom.cpp:292
> #3  0x004a3834 in StartIsom () at
> /home/abhishek/develop/gateway-app/GatewayApp/source/WebServer/isom.cpp:592
> #4  0x00486494 in ns_Isom::isom_start_function (ptr=0x0) at
> /home/abhishek/develop/gateway-app/GatewayApp/source/GatewayAppMain.cpp:646
> #5  0x76cc4afa in start_thread (arg=0xa9c8b261) at
> /usr/src/debug/glibc/2.28-r0/git/nptl/pthread_create.c:486
> #6  0x76ab538c in ?? () at ../sysdeps/unix/sysv/linux/arm/clone.S:73 from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/lib/libc.so.6
> Backtrace stopped: previous frame identical to this frame (corrupt stack?)
>
> Thread 2 (LWP 3204):
> #0  __libc_do_syscall () at libc-do-syscall.S:48
> #1  0x76cc5b18 in __GI___pthread_timedjoin_ex (threadid=1873773472,
> thread_return=0x0, abstime=<optimized out>, block=<optimized out>)
>     at /usr/src/debug/glibc/2.28-r0/git/nptl/pthread_join_common.c:89
> #2  0x76c40f3a in __gthread_join (__value_ptr=0x0, __threadid=<optimized
> out>)
>     at
>
> /usr/src/debug/gcc-runtime/7.3.0-r0/arm-fslc-linux-gnueabi/libstdc++-v3/include/arm-fslc-linux-gnueabi/bits/gthr-default.h:668
> #3  std::thread::join (this=this@entry=0x7ebe1784) at
> /usr/src/debug/gcc-runtime/7.3.0-r0/libstdc++-v3/src/c++11/thread.cc:136
> #4  0x00470198 in main (argc=<optimized out>, argv=<optimized out>) at
> /home/abhishek/develop/gateway-app/GatewayApp/source/GatewayAppMain.cpp:599
>
> Thread 1 (LWP 3751):
> #0  0x769ec67a in Curl_strncasecompare () from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/usr/lib/libcurl.so.4
> #1  0x769ead58 in Curl_checkheaders () from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/usr/lib/libcurl.so.4
> #2  0x769de8fa in Curl_http () from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/usr/lib/libcurl.so.4
> #3  0x769f0e5c in multi_runsingle () from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/usr/lib/libcurl.so.4
> #4  0x769f1708 in curl_multi_perform () from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/usr/lib/libcurl.so.4
> #5  0x769ec986 in curl_easy_perform () from
>
> /opt/iotgw-debug/2.5.3/sysroots/armv7at2hf-neon-fslc-linux-gnueabi/usr/lib/libcurl.so.4
> #6  0x76eb433e in ?? ()
> Backtrace stopped: previous frame identical to this frame (corrupt stack?)
>