Qt on i.MX6 with -platform eglfs -> Segmentation fault

I have cross-compiled Qt 5.1.1 for an i.MX6 powered Nitrogen6x board running Debian 7 (wheezy).

I have configured Qt with the -egl parameter and eglfs has been listed as QPA backend in the configure output.

However if I try to run a small example application with the -platform eglfs parameter I am running into this error:

stdin: is not a tty
[     1] HAL user version 4.6.9 build 6622 Aug 15 2013 13:22:40
[     2] HAL kernel version 4.6.9 build 1210
QML debugging is enabled. Only use this in a safe environment.
bash: line 1:  3673 Segmentation fault      DISPLAY=:0.0 /opt/Test/bin/Test -platform eglfs
Remote application finished with exit code 139.

OpenGL ES2 and EGL are installed on the board and can be found in /usr/lib and /usr/include. Sadly I couldn't find proper documentation for eglfs, so I am hoping that someone around here has made some experiences with it.

This is the backtrace output:

    run Test-platform eglfs
Starting program: /opt/Test/bin/Test Test -platform eglfs
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
[     1] HAL user version 4.6.9 build 6622 Aug 15 2013 13:31:17
[     2] HAL kernel version 4.6.9 build 1210
QML debugging is enabled. Only use this in a safe environment.
[New Thread 0x2c6b7460 (LWP 4057)]

Program received signal SIGSEGV, Segmentation fault.
0x2bab6f48 in gcoHAL_QueryChipCount () from /usr/lib/libGAL.so
(gdb) backrace full
Undefined command: "backrace".  Try "help".
(gdb) backrace full[1@t
#0  0x2bab6f48 in gcoHAL_QueryChipCount () from /usr/lib/libGAL.so
No symbol table info available.
#1  0x2ba7ccbc in veglGetThreadData () from /usr/lib/libEGL.so.1
No symbol table info available.
#2  0x2ba74cd0 in eglBindAPI () from /usr/lib/libEGL.so.1
No symbol table info available.
#3  0x2be41934 in ?? () from /usr/local/Qt-Debian/plugins/platforms/libqeglfs.so
No symbol table info available.
#4  0x2be41934 in ?? () from /usr/local/Qt-Debian/plugins/platforms/libqeglfs.so
No symbol table info available.
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) info registers
r0             0x1  1
r1             0x23e54  147028
r2             0x738    1848
r3             0x0  0
r4             0x2bb67d84   733379972
r5             0x23e18  146968
r6             0x2e70c  190220
r7             0x2b430198   725811608
r8             0x7efff9e8   2130704872
r9             0x8  8
r10            0x2b0725c4   721888708
r11            0x7efffae0   2130705120
r12            0x2bab6f1c   732655388
sp             0x7efff8f0   0x7efff8f0
lr             0x2ba7ccbc   732417212
pc             0x2bab6f48   0x2bab6f48 <gcoHAL_QueryChipCount+44>
cpsr           0x80000010   -2147483632
(gdb) x/16i $pc
=> 0x2bab6f48 <gcoHAL_QueryChipCount+44>:   ldr r3, [r3, #12]
   0x2bab6f4c <gcoHAL_QueryChipCount+48>:   sub r2, r3, #1
   0x2bab6f50 <gcoHAL_QueryChipCount+52>:   cmp r2, #2
   0x2bab6f54 <gcoHAL_QueryChipCount+56>:   bhi 0x2bab6f70 <gcoHAL_QueryChipCount+84>
   0x2bab6f58 <gcoHAL_QueryChipCount+60>:   ldr r2, [r4]
   0x2bab6f5c <gcoHAL_QueryChipCount+64>:   mov r0, #0
   0x2bab6f60 <gcoHAL_QueryChipCount+68>:   str r3, [r1]
   0x2bab6f64 <gcoHAL_QueryChipCount+72>:   add r3, r2, #1
   0x2bab6f68 <gcoHAL_QueryChipCount+76>:   str r3, [r4]
   0x2bab6f6c <gcoHAL_QueryChipCount+80>:   pop {r4, pc}
   0x2bab6f70 <gcoHAL_QueryChipCount+84>:   mvn r0, #8
   0x2bab6f74 <gcoHAL_QueryChipCount+88>:   bl  0x2baad5fc
   0x2bab6f78 <gcoHAL_QueryChipCount+92>:   ldr r3, [r4]
   0x2bab6f7c <gcoHAL_QueryChipCount+96>:   mvn r0, #8
   0x2bab6f80 <gcoHAL_QueryChipCount+100>:  add r3, r3, #1
   0x2bab6f84 <gcoHAL_QueryChipCount+104>:  str r3, [r4]
(gdb) thread apply all backtrace

Thread 2 (Thread 0x2c6b7460 (LWP 4057)):
#0  0x2b52ef96 in ?? () from /lib/arm-linux-gnueabihf/libc.so.6
#1  0x2b568634 in _IO_file_close () from /lib/arm-linux-gnueabihf/libc.so.6
#2  0x2b568ffe in _IO_file_close_it () from /lib/arm-linux-gnueabihf/libc.so.6
#3  0x2b56113a in fclose () from /lib/arm-linux-gnueabihf/libc.so.6
#4  0x2bea8d00 in udev_new () from /lib/arm-linux-gnueabihf/libudev.so.0
#5  0x2be7d2e4 in ?? () from /usr/local/Qt-Debian/plugins/platforms/libqeglfs.so
#6  0x2be7d2e4 in ?? () from /usr/local/Qt-Debian/plugins/platforms/libqeglfs.so
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

Thread 1 (Thread 0x2bcb9220 (LWP 4056)):
#0  0x2bab6f48 in gcoHAL_QueryChipCount () from /usr/lib/libGAL.so
#1  0x2ba7ccbc in veglGetThreadData () from /usr/lib/libEGL.so.1
#2  0x2ba74cd0 in eglBindAPI () from /usr/lib/libEGL.so.1
#3  0x2be41934 in ?? () from /usr/local/Qt-Debian/plugins/platforms/libqeglfs.so
#4  0x2be41934 in ?? () from /usr/local/Qt-Debian/plugins/platforms/libqeglfs.so
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) quit

How could I possibly fix that error?

I have the exact same crash on a MarSBoard running an egl fb application on a Yocto image created with recipes from https://github.com/silmerusse/meta-robomind. I had to copy the EGL/OpenGL related stuff from http://repository.timesys.com/buildsources/g/gpu-viv-bin-mx6q/. In my case galcore.ko is builtin.

Edit: Check that you have /dev/galcore and that its permission are crw.rw.rw. (otherwise sudo chmod 666 /dev/galcore). If you don't have /dev/galcore, try insmod /lib/modules/..../kernel/drivers/mxc/gpu-viv/galcore.ko. These steps fixed the crash for me on an ubuntu image. On the Yocto image the galcore driver is builtin, and seems to be there but I still get the crash.

Edit: The crash in the Yocto image was caused by the wrong version of the EGL/GAL.so libs. Apparently the galcore driver built into the kernel has version 4.6.9.6622. It requires libs from gpu-viv-bin-mx6q-3.0.35-4.1.0. Using those libs and manually copying them into /usr/lib my fb application runs fine, using hardware OpenGLES 2.0 and hardware decoding of a h264 video.