On Thu, May 20, 2021 at 10:10:14AM +0200, Matthieu Herrb wrote:
> > procedure a few times now and it unfortunately does not produce any
> > coredumps
> > or traces.
>
> When the X server is locked up I can still ssh into the machine and
> attach a debugger to the running process. I've got a few backtraces
> from that, but without full symbols it's even harder to understand
> what's going on.
>
> I suspect issues with our futex implementation; in every case I find
> one thread stuck in a drm ioctl while others are blocked on futex
> waits.
>
> Running an X server + Mesa fully built with debug symbols seem to make
> the issue less frequent and when it happenned I didn't have time to
> launch a debugger on it so far...
>
Running with this xorg.conf only
#Section "Device"
# Identifier "amdgpu-modesetting"
# Driver "modesetting"
#EndSection
Section "ServerFlags"
Option "NoTrapSignals" "true"
EndSection
# per Alexandre Ratchov
Section "Device"
Identifier "Card0"
Driver "modesetting"
Option "SWCursor" "on"
Option "PageFlip" "off"
Option "AccelMethod" "none"
EndSection
Section "Module"
Disable "glx"
EndSection
I got a X crash on startup but was able to log in via ssh.
gdb reads all symbols as far as I can see:
[Thu May 20 14:00:09] peter@zelda:~$ doas gdb /usr/X11R6/bin/Xorg 40595
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This GDB was configured as "amd64-unknown-openbsd6.9"...
Attaching to program: /usr/X11R6/bin/Xorg, process 40595
Reading symbols from /usr/lib/libpthread.so.26.1...done.
Loaded symbols for /usr/lib/libpthread.so.26.1
Loaded symbols for /usr/X11R6/bin/Xorg
Symbols already loaded for /usr/lib/libpthread.so.26.1
Reading symbols from /usr/X11R6/lib/libpciaccess.so.2.0...done.
Loaded symbols for /usr/X11R6/lib/libpciaccess.so.2.0
Reading symbols from /usr/X11R6/lib/libdrm.so.7.9...done.
Loaded symbols for /usr/X11R6/lib/libdrm.so.7.9
Reading symbols from /usr/X11R6/lib/libpixman-1.so.38.4...done.
Loaded symbols for /usr/X11R6/lib/libpixman-1.so.38.4
Reading symbols from /usr/X11R6/lib/libXfont2.so.2.0...done.
Loaded symbols for /usr/X11R6/lib/libXfont2.so.2.0
Reading symbols from /usr/X11R6/lib/libfontenc.so.4.0...done.
Loaded symbols for /usr/X11R6/lib/libfontenc.so.4.0
Reading symbols from /usr/X11R6/lib/libfreetype.so.30.0...done.
Loaded symbols for /usr/X11R6/lib/libfreetype.so.30.0
Reading symbols from /usr/lib/libz.so.5.0...done.
Loaded symbols for /usr/lib/libz.so.5.0
Reading symbols from /usr/X11R6/lib/libXau.so.10.0...done.
Loaded symbols for /usr/X11R6/lib/libXau.so.10.0
Reading symbols from /usr/X11R6/lib/libxshmfence.so.0.0...done.
Loaded symbols for /usr/X11R6/lib/libxshmfence.so.0.0
Reading symbols from /usr/X11R6/lib/libXdmcp.so.11.0...done.
Loaded symbols for /usr/X11R6/lib/libXdmcp.so.11.0
Reading symbols from /usr/lib/libkvm.so.17.0...done.
Loaded symbols for /usr/lib/libkvm.so.17.0
Reading symbols from /usr/lib/libm.so.10.1...done.
Loaded symbols for /usr/lib/libm.so.10.1
Reading symbols from /usr/lib/libc.so.96.0...done.
Loaded symbols for /usr/lib/libc.so.96.0
Reading symbols from /usr/libexec/ld.so...Error while reading shared library
symbols:
Dwarf Error: wrong version in compilation unit header (is 4, should be 2) [in
module /usr/libexec/ld.so]
Reading symbols from /usr/X11R6/lib/modules/drivers/modesetting_drv.so...done.
Loaded symbols for /usr/X11R6/lib/modules/drivers/modesetting_drv.so
Reading symbols from /usr/X11R6/lib/modules/libfb.so...done.
Loaded symbols for /usr/X11R6/lib/modules/libfb.so
Reading symbols from /usr/X11R6/lib/modules/libshadow.so...done.
Loaded symbols for /usr/X11R6/lib/modules/libshadow.so
Reading symbols from /usr/X11R6/lib/modules/input/kbd_drv.so...done.
Loaded symbols for /usr/X11R6/lib/modules/input/kbd_drv.so
Reading symbols from /usr/X11R6/lib/modules/input/ws_drv.so...done.
Loaded symbols for /usr/X11R6/lib/modules/input/ws_drv.so
[Switching to thread 113495]
_thread_sys_poll () at /tmp/-:3
3 /tmp/-: No such file or directory.
in /tmp/-
(gdb) bt
#0 _thread_sys_poll () at /tmp/-:3
#1 0x000002b3cdac8c6e in _libc_poll_cancel (fds=Unhandled dwarf expression
opcode 0xa3
) at /usr/src/lib/libc/sys/w_poll.c:27
#2 0x000002b14afd99cb in ospoll_wait () from /usr/X11R6/bin/Xorg
#3 0x000002b14afd739c in InputThreadDoWork () from /usr/X11R6/bin/Xorg
#4 0x000002b3f0b25471 in _rthread_start (v=Unhandled dwarf expression opcode
0xa3
) at /usr/src/lib/librthread/rthread.c:96
#5 0x000002b3cdb0e18a in __tfork_thread () at
/usr/src/lib/libc/arch/amd64/sys/tfork_thread.S:84
#6 0x000002b3cdb0e18a in __tfork_thread () at
/usr/src/lib/libc/arch/amd64/sys/tfork_thread.S:84
Previous frame identical to this frame (corrupt stack?)
Then
(gdb) list
84 call 0b
85
86 /*
87 * Thread exit system call
88 */
89 movl $SYS___threxit, %eax
90 xorl %edi, %edi
91 syscall
92 int3
93
Current language: auto; currently asm
(gdb) list
94 /*
95 * Branch here if the thread creation fails:
96 */
97 2:
98 SET_ERRNO
99 ret
100 .cfi_endproc
101 END(__tfork_thread)
(gdb) list
Line number 102 out of range; /usr/src/lib/libc/arch/amd64/sys/tfork_thread.S
has 101 lines.
Program received signal SIGSTOP, Stopped (signal).
[Switching to thread 223487]
_thread_sys_poll () at /tmp/-:3
3 /tmp/-: No such file or directory.
in /tmp/-
(gdb) continue
Continuing.
Program received signal SIGSTOP, Stopped (signal).
[Switching to thread 223487]
_thread_sys_poll () at /tmp/-:3
3 /tmp/-: No such file or directory.
in /tmp/-
(gdb)
Continuing.
After which I don't get any new results from further continues, so I tried
^C
Program received signal SIGINT, Interrupt.
_thread_sys_poll () at /tmp/-:3
3 in /tmp/-
(gdb) print
The history is empty.
(gdb) list
1 in /tmp/-
(gdb) continue
Continuing.
^C
Program received signal SIGINT, Interrupt.
_thread_sys_poll () at /tmp/-:3
3 in /tmp/-
(gdb) bt
#0 _thread_sys_poll () at /tmp/-:3
#1 0x000002b3cdac8c6e in _libc_poll_cancel (fds=Unhandled dwarf expression
opcode 0xa3
) at /usr/src/lib/libc/sys/w_poll.c:27
#2 0x000002b14afd99cb in ospoll_wait () from /usr/X11R6/bin/Xorg
#3 0x000002b14afd1726 in WaitForSomething () from /usr/X11R6/bin/Xorg
#4 0x000002b14ae3338c in Dispatch () from /usr/X11R6/bin/Xorg
#5 0x000002b14ae3e5ec in dix_main () from /usr/X11R6/bin/Xorg
#6 0x000002b14ae25180 in _start () from /usr/X11R6/bin/Xorg
#7 0x0000000000000000 in ?? ()
(gdb)
I hope this is at least a little useful.
--
Peter N. M. Hansteen, member of the first RFC 1149 implementation team
http://bsdly.blogspot.com/ http://www.bsdly.net/ http://www.nuug.no/
"Remember to set the evil bit on all malicious network traffic"
delilah spamd[29949]: 85.152.224.147: disconnected after 42673 seconds.
