Request: add pc-address

[skoperst]

Hi, it will be useful to get the pc-address , something like this:

thread: 0, lwp: 3840, type: 0
#0 0x00007f18c7270376 + 0x47c62a in __pthread_cond_wait()+534 in /lib/x86_64-linux-gnu/libpthread.so.0 at futex-internal.h:183
#1 0x00007f18badfe62b + 0x10376 in () in /usr/lib/x86_64-linux-gnu/dri/radeonsi_dri.so
#2 0x00007f18badfe23b + 0x10223 in () in /usr/lib/x86_64-linux-gnu/dri/radeonsi_dri.so

What do you think?

[peadar]

Hey,
I'm not sure what you mean - for example -
#0 0x00007fada8f49e3c in __sigsuspend()+28 in /lib64/libc.so.6 at sigsuspend.c:26

In this case 0x00007fada8f49e3c is the PC (I assume you program counter, or, on x86, the RIP register)
The symbol "__sigsuspend" starts 28 bytes before that, hence the +28 there, to indicate you're 28 bytes into that function.

What, in your case, do you intend the 0x47c62a above to indicate at the topmost frame?

[skoperst]

Hey, so my previous example is not correct, I'll try to explain again.
Here I ran '/usr/bin/sleep' and used pstack on it:
$ sudo ~/projects/pstack/build/pstack 171909

process: /proc/171909/mem
thread: 0, lwp: 171909, type: 0
#0  0x00007fdeb737e334 in __clock_nanosleep()+84 in /lib/x86_64-linux-gnu/libc.so.6 at clock_nanosleep.c:78
#1  0x00007fdeb7384047 in __nanosleep()+22 in /lib/x86_64-linux-gnu/libc.so.6 at nanosleep.c:27
warning: no compiled support for LZMA - can't decode debug data in /usr/bin/sleep
#2  0x00005635f46f0827 in <unknown>() in /usr/bin/sleep
#3  0x00005635f46f0600 in <unknown>() in /usr/bin/sleep
#4  0x00005635f46ed7b0 in <unknown>() in /usr/bin/sleep
#5  0x00007fdeb72c50b3 in __libc_start_main()+242 in /lib/x86_64-linux-gnu/libc.so.6 at libc-start.c:308
#6  0x00005635f46ed87e in <unknown>() in /usr/bin/sleep

This is my maps:

sudo cat /proc/171909/maps
5635f46eb000-5635f46ed000 r--p 00000000 08:02 12846161                   /usr/bin/sleep
5635f46ed000-5635f46f1000 r-xp 00002000 08:02 12846161                   /usr/bin/sleep
5635f46f1000-5635f46f3000 r--p 00006000 08:02 12846161                   /usr/bin/sleep
5635f46f4000-5635f46f5000 r--p 00008000 08:02 12846161                   /usr/bin/sleep
5635f46f5000-5635f46f6000 rw-p 00009000 08:02 12846161                   /usr/bin/sleep
5635f539b000-5635f53bc000 rw-p 00000000 00:00 0                          [heap]
7fdeb6d2e000-7fdeb729e000 r--p 00000000 08:02 12847762                   /usr/lib/locale/locale-archive
7fdeb729e000-7fdeb72c3000 r--p 00000000 08:02 12847219                   /usr/lib/x86_64-linux-gnu/libc-2.31.so
7fdeb72c3000-7fdeb743b000 r-xp 00025000 08:02 12847219                   /usr/lib/x86_64-linux-gnu/libc-2.31.so
7fdeb743b000-7fdeb7485000 r--p 0019d000 08:02 12847219                   /usr/lib/x86_64-linux-gnu/libc-2.31.so
7fdeb7485000-7fdeb7486000 ---p 001e7000 08:02 12847219                   /usr/lib/x86_64-linux-gnu/libc-2.31.so
7fdeb7486000-7fdeb7489000 r--p 001e7000 08:02 12847219                   /usr/lib/x86_64-linux-gnu/libc-2.31.so
7fdeb7489000-7fdeb748c000 rw-p 001ea000 08:02 12847219                   /usr/lib/x86_64-linux-gnu/libc-2.31.so
7fdeb748c000-7fdeb7492000 rw-p 00000000 00:00 0 
7fdeb74b6000-7fdeb74b7000 r--p 00000000 08:02 12845269                   /usr/lib/x86_64-linux-gnu/ld-2.31.so
7fdeb74b7000-7fdeb74da000 r-xp 00001000 08:02 12845269                   /usr/lib/x86_64-linux-gnu/ld-2.31.so
7fdeb74da000-7fdeb74e2000 r--p 00024000 08:02 12845269                   /usr/lib/x86_64-linux-gnu/ld-2.31.so
7fdeb74e3000-7fdeb74e4000 r--p 0002c000 08:02 12845269                   /usr/lib/x86_64-linux-gnu/ld-2.31.so
7fdeb74e4000-7fdeb74e5000 rw-p 0002d000 08:02 12845269                   /usr/lib/x86_64-linux-gnu/ld-2.31.so
7fdeb74e5000-7fdeb74e6000 rw-p 00000000 00:00 0 
7fff5da5b000-7fff5da7c000 rw-p 00000000 00:00 0                          [stack]
7fff5dae4000-7fff5dae8000 r--p 00000000 00:00 0                          [vvar]
7fff5dae8000-7fff5daea000 r-xp 00000000 00:00 0                          [vdso]
ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0                  [vsyscall]

Then I want to investigate where exactly is frame number 2:
#2 0x00005635f46f0827 in <unknown>() in /usr/bin/sleep

It could be easier if it was shown as:
#2 0x00005635f46f0827 in <unknown>() [/usr/bin/sleep + 0x5826] in /usr/bin/sleep @0x5635f46eb000+0x5826

This way I can go to my non-stripped version of /usr/bin/sleep and use gdb with the command: info symbol 0x5826

Hope it makes more sense now.

[peadar]

Ah You want the instruction pointer relative to the ELF object it's contained in. That's pretty simple, sure, I can add that as an option, I guess. You know you can give pstack the unstripped binary too, at least for the executable, right? (I realise you might be running pstack and gdb in two separate environments)

…

On Sat 6 Feb 2021, 22:25 skoperst, ***@***.***> wrote: Hey, so my previous example is not correct, I'll try to explain again. Here I ran '/usr/bin/sleep' and used pstack on it: $ sudo ~/projects/pstack/build/pstack 171909 process: /proc/171909/mem thread: 0, lwp: 171909, type: 0 #0 0x00007fdeb737e334 in __clock_nanosleep()+84 in /lib/x86_64-linux-gnu/libc.so.6 at clock_nanosleep.c:78 #1 0x00007fdeb7384047 in __nanosleep()+22 in /lib/x86_64-linux-gnu/libc.so.6 at nanosleep.c:27 warning: no compiled support for LZMA - can't decode debug data in /usr/bin/sleep #2 0x00005635f46f0827 in <unknown>() in /usr/bin/sleep #3 0x00005635f46f0600 in <unknown>() in /usr/bin/sleep #4 0x00005635f46ed7b0 in <unknown>() in /usr/bin/sleep #5 0x00007fdeb72c50b3 in __libc_start_main()+242 in /lib/x86_64-linux-gnu/libc.so.6 at libc-start.c:308 #6 0x00005635f46ed87e in <unknown>() in /usr/bin/sleep This is my maps: sudo cat /proc/171909/maps 5635f46eb000-5635f46ed000 r--p 00000000 08:02 12846161 /usr/bin/sleep 5635f46ed000-5635f46f1000 r-xp 00002000 08:02 12846161 /usr/bin/sleep 5635f46f1000-5635f46f3000 r--p 00006000 08:02 12846161 /usr/bin/sleep 5635f46f4000-5635f46f5000 r--p 00008000 08:02 12846161 /usr/bin/sleep 5635f46f5000-5635f46f6000 rw-p 00009000 08:02 12846161 /usr/bin/sleep 5635f539b000-5635f53bc000 rw-p 00000000 00:00 0 [heap] 7fdeb6d2e000-7fdeb729e000 r--p 00000000 08:02 12847762 /usr/lib/locale/locale-archive 7fdeb729e000-7fdeb72c3000 r--p 00000000 08:02 12847219 /usr/lib/x86_64-linux-gnu/libc-2.31.so 7fdeb72c3000-7fdeb743b000 r-xp 00025000 08:02 12847219 /usr/lib/x86_64-linux-gnu/libc-2.31.so 7fdeb743b000-7fdeb7485000 r--p 0019d000 08:02 12847219 /usr/lib/x86_64-linux-gnu/libc-2.31.so 7fdeb7485000-7fdeb7486000 ---p 001e7000 08:02 12847219 /usr/lib/x86_64-linux-gnu/libc-2.31.so 7fdeb7486000-7fdeb7489000 r--p 001e7000 08:02 12847219 /usr/lib/x86_64-linux-gnu/libc-2.31.so 7fdeb7489000-7fdeb748c000 rw-p 001ea000 08:02 12847219 /usr/lib/x86_64-linux-gnu/libc-2.31.so 7fdeb748c000-7fdeb7492000 rw-p 00000000 00:00 0 7fdeb74b6000-7fdeb74b7000 r--p 00000000 08:02 12845269 /usr/lib/x86_64-linux-gnu/ld-2.31.so 7fdeb74b7000-7fdeb74da000 r-xp 00001000 08:02 12845269 /usr/lib/x86_64-linux-gnu/ld-2.31.so 7fdeb74da000-7fdeb74e2000 r--p 00024000 08:02 12845269 /usr/lib/x86_64-linux-gnu/ld-2.31.so 7fdeb74e3000-7fdeb74e4000 r--p 0002c000 08:02 12845269 /usr/lib/x86_64-linux-gnu/ld-2.31.so 7fdeb74e4000-7fdeb74e5000 rw-p 0002d000 08:02 12845269 /usr/lib/x86_64-linux-gnu/ld-2.31.so 7fdeb74e5000-7fdeb74e6000 rw-p 00000000 00:00 0 7fff5da5b000-7fff5da7c000 rw-p 00000000 00:00 0 [stack] 7fff5dae4000-7fff5dae8000 r--p 00000000 00:00 0 [vvar] 7fff5dae8000-7fff5daea000 r-xp 00000000 00:00 0 [vdso] ffffffffff600000-ffffffffff601000 --xp 00000000 00:00 0 [vsyscall] Then, I want to take gdb and look at the 2nd frame: #2 <#2> 0x00005635f46f0827 in () in /usr/bin/sleep It could be easier if it was shown as: #2 <#2> 0x00005635f46f0827 in () [/usr/bin/sleep + 0x5826] in /usr/bin/sleep @0x5635f46eb000+0x5826 Is it clearer now? This way I can go to my non-stripped version of /usr/bin/sleep and use gdb with the command: info symbol 0x5826 — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#6 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAE6NDJ2VKLXONUJYWUDTE3S5W6XJANCNFSM4VXELQIA> .

[peadar]

Fixed in master. Pass -v, and get "@offset" added to the image name. LMK if it works for you -