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New crash of TN-Grid app on Ryzen CPUs, this time in SSE2 app version

Question asked by sirzooro on Dec 17, 2018
Latest reply on Jan 2, 2019 by ryzenmaster2017

1.5 half year ago I reported problem with TN-Grid FMA app which crashed on Ryzens: New Ryzen FMA bug  . This bug is fixed now, thanks.

 

Users of TN-Grid are now complaining that SSE2 version of this app is crashing on Ryzen. It affects Linux and Windows app versions. Here are two example crash reports from Linux app:

 

process exited with code 193 (0xc1, -63)</message>

<stderr_txt>

Start  @ Thu Dec  6 19:49:43 2018

SIGILL: illegal instruction

Stack trace (5 frames):

../../projects/gene.disi.unitn.it_test/gene_pcim_v1.10_linux64__sse2[0x42a280]

/lib/x86_64-linux-gnu/libpthread.so.0(+0x12890)[0x7fd773051890]

../../projects/gene.disi.unitn.it_test/gene_pcim_v1.10_linux64__sse2[0x418754]

/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7)[0x7fd772c6fb97]

../../projects/gene.disi.unitn.it_test/gene_pcim_v1.10_linux64__sse2[0x404a97]

 

process exited with code 193 (0xc1, -63)</message>

<stderr_txt>

Start  @ Fri Dec  7 21:58:04 2018

SIGSEGV: segmentation violation

Stack trace (5 frames):

../../projects/gene.disi.unitn.it_test/gene_pcim_v1.10_linux64__sse2[0x42a280]

/lib/x86_64-linux-gnu/libpthread.so.0(+0x12890)[0x7f14998a3890]

../../projects/gene.disi.unitn.it_test/gene_pcim_v1.10_linux64__sse2[0x41876a]

/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xe7)[0x7f14994c1b97]

../../projects/gene.disi.unitn.it_test/gene_pcim_v1.10_linux64__sse2[0x404a97]

 

Apps crashed because of illegal instruction at 0x418754 and 0x41876a. I checked this with gdb. In both cases address is in the middle of other instruction. In first case opcode at reported address is invalid. In second it was decoded as SUB, and this instruction triggered segmentation fault.

 

Both crashed reported here happened on following CPU and OS:

 

AuthenticAMD

AMD Ryzen 7 2700 Eight-Core Processor [Family 23 Model 8 Stepping 2]

Linux Ubuntu

Ubuntu 18.04.1 LTS [4.15.0-42-generic|libc 2.27 (Ubuntu GLIBC 2.27-3ubuntu1)]

 

Direct link to app which exhibits this problem: https://gene.disi.unitn.it/test/download/gene_pcim_v1.10_linux64__sse2

 

Link to thread on TN-Grid forum where this problem was reported: sse2 vs avx

Outcomes