[Pkg-opencl-devel] Bug#1016572: ocl-icd-libopencl1: Segmentation fault in clGetExtensionFunctionAddress (name=0x76f97440 "clIcdGetPlatformIDsKHR")

[Andreas Beckmann]

Control: reassign -1 clinfo

On 03/08/2022 08.54, Anton Qiu wrote:
> Package: ocl-icd-libopencl1
> Version: 2.2.14-2

> When running clinfo in Raspberry Pi 3 with VC4CL manually installed the clinfo program reported Segmentation fault.

According to the backtrace, the segfault happened in VC4CL, so either 
the bug is there (e.g. it should return an error when queried for 
something unknown) or in clinfo (e.g. because it tries to call something 
it shouldn't).

> Using gdb, I notice the the exception happened when calling clGetExtensionFunctionAddress ("clIcdGetPlatformIDsKHR")
> 
> here are the detail
> $ sudo gdb clinfo
> (gdb) r
> Program received signal SIGSEGV, Segmentation fault.
> 0x0008dc40 in ?? ()
> (gdb) bt full
> #0  0x0008dc40 in ?? ()
> No symbol table info available.
> #1  0x76d47564 in clGetExtensionFunctionAddress (name=0x76f97440 "clIcdGetPlatformIDsKHR")
>      at /home/anton/rpi3opencl/VC4CL/src/extensions.cpp:53
> No locals.
> #2  0x76f918e4 in ?? () from /lib/arm-linux-gnueabihf/libOpenCL.so.1
> No symbol table info available.
> 
> (gdb) info register
> r0             0x8d8e4             579812
> r1             0x76f97440          1996059712
> r2             0x53                83
> r3             0x8dc40             580672
> r4             0x76d47534          1993635124
> r5             0x76d48c10          1993640976
> r6             0x0                 0
> r7             0x0                 0
> r8             0x76f97440          1996059712
> r9             0x41350             267088
> r10            0x411b8             266680
> r11            0x7efff4b4          2130703540
> r12            0x76fa8f6c          1996132204
> sp             0x7efff4a8          0x7efff4a8
> lr             0x76d47564          1993635172
> pc             0x8dc40             0x8dc40
> cpsr           0x20000010          536870928
> fpscr          0x80000000          -2147483648
> 
> (gdb) disassemble 0x76d47564
> Dump of assembler code for function clGetExtensionFunctionAddress(char const*):
>     0x76d47534 <+0>:     push    {r11, lr}
>     0x76d47538 <+4>:     add     r11, sp, #4
>     0x76d4753c <+8>:     sub     sp, sp, #8
>     0x76d47540 <+12>:    str     r0, [r11, #-8]
>     0x76d47544 <+16>:    bl      0x76cf9bd4 <_ZN5vc4cl8Platform16getVC4CLPlatformEv at plt>
>     0x76d47548 <+20>:    mov     r3, r0
>     0x76d4754c <+24>:    mov     r0, r3
>     0x76d47550 <+28>:    bl      0x76cf0874 <_ZN5vc4cl6ObjectI15_cl_platform_idLin32EE6toBaseEv at plt>
>     0x76d47554 <+32>:    mov     r3, r0
>     0x76d47558 <+36>:    ldr     r1, [r11, #-8]
>     0x76d4755c <+40>:    mov     r0, r3
>     0x76d47560 <+44>:    bl      0x76cf4cfc <clGetExtensionFunctionAddressForPlatform at plt>
>     0x76d47564 <+48>:    mov     r3, r0
>     0x76d47568 <+52>:    mov     r0, r3
>     0x76d4756c <+56>:    sub     sp, r11, #4
>     0x76d47570 <+60>:    pop     {r11, pc}
> End of assembler dump.
> 
> Looking at the information above, it seems that the exception happens when calling clGetExtensionFunctionAddressForPlatform()
> for "clIcdGetPlatformIDsKHR".
> 
> The clinfo program was compiled from source based on repository "https://github.com/Oblomov/clinfo" on 02 Aug 2022.
> 
> 
> -- System Information:
> Distributor ID:	Raspbian
> Description:	Raspbian GNU/Linux 11 (bullseye)
> Release:	11
> Codename:	bullseye
> Architecture: armv7l
> 
> Kernel: Linux 5.15.56-v7+ (SMP w/4 CPU threads)
> Kernel taint flags: TAINT_CRAP
> Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8), LANGUAGE not set
> Shell: /bin/sh linked to /usr/bin/dash
> Init: systemd (via /run/systemd/system)
> 
> Versions of packages ocl-icd-libopencl1 depends on:
> ii  libc6  2.31-13+rpt2+rpi1+deb11u3
> 
> ocl-icd-libopencl1 recommends no packages.
> 
> Versions of packages ocl-icd-libopencl1 suggests:
> pn  opencl-icd  <none>
> 

Andreas