We are observing processes that receive a totally unexpected realtime signal 34 during shutdown. I set up a signal handler with sigaction() with SA_SIGINFO that prints information about the sender of the signal and then calls abort(). With this handler I can see that the signal is coming from the process itself and the stacktrace I get look like this:
(gdb) bt
#0 0x0000003ee5e32925 in raise () from /lib64/libc.so.6
#1 0x0000003ee5e34105 in abort () from /lib64/libc.so.6
#2 0x00007ff36b66e98f in qtutility::qtutil::diagnoseRtSignal (sig=Unhandled dwarf expression opcode 0xf3
)
at /home/jenkins/workspace/personal-ts-7.0-all-tests-2/arch/rhel6_x86_64_ev6/qtutility/src/qtutil.cc:723
#3 0x0000003463eb3e33 in ?? () from /usr/lib64/libGL.so.1
#4 0x0000003463eb4890 in ?? () from /usr/lib64/libGL.so.1
#5
#6 0x0000003ee5ee53c9 in syscall () from /lib64/libc.so.6
#7 0x0000003463eb4a05 in ?? () from /usr/lib64/libGL.so.1
#8 0x0000003463eb4e8f in ?? () from /usr/lib64/libGL.so.1
#9 0x0000003463eb50cc in ?? () from /usr/lib64/libGL.so.1
#10 0x0000003463eb51ca in ?? () from /usr/lib64/libGL.so.1
#11 0x0000003463e900f5 in ?? () from /usr/lib64/libGL.so.1
#12 0x0000003ee560ebac in _dl_fini () from /lib64/ld-linux-x86-64.so.2
#13 0x0000003ee5e35e22 in exit () from /lib64/libc.so.6
#14 0x0000003ee5e1ed24 in __libc_start_main () from /lib64/libc.so.6
#15 0x0000000000409ab1 in _start ()
As you can see the program is executing in the nvidia driver when it receives the signal. Based on this I googled a bit and found this webkit bug report that is also about an unexpected signal 34 being received. The bug report attributes this to a bug in the NVIDIA driver.
https://bugs.webkit.org/show_bug.cgi?id=101614#c8
This problem is observed on a VM on an ESXi 5.5 hypervisor where the VM is assigned an NVIDIA Quadro K2000 GPU via passthrough (vDGA style). It happens when the VM (and the ESXi host) is under heavy load.
I’m addressing this forum in the hope that an NVIDIA driver developer can tell me whether the NVIDIA driver could be the culprit and what I can do about it, if that is indeed the case.
Best regards,
Thomas