I've enabled coproc_debug and get these logs:

Tue 04 Mar 2014 11:46:13 AM CST | | NVIDIA drivers present but no GPUs found
Tue 04 Mar 2014 11:46:13 AM CST | | No ATI library found
Tue 04 Mar 2014 11:46:13 AM CST | | OpenCL library present but no OpenCL-capable GPUs found
Tue 04 Mar 2014 11:46:13 AM CST | | No usable GPUs found

System is Arch Linux x86_64. Same config with the only difference is an older version of nvidia driver (331.49) worked with boinc flawlessly.

Any help will be really appreciated, thanks!

Update:

Wrote a small test code (mostly copied from boinc/client/gpu_nvidia.cpp), which outputs 999 with 334.21 driver, but 0 with 331.49 driver. So seems an upstream bug?

#include <stdio.h>
#include <dlfcn.h>
int main() {
  void *cudalib = dlopen("libcuda.so", RTLD_NOW);
  int (*__cuInit)(unsigned int) = (int(*)(unsigned int)) dlsym( cudalib, "cuInit" );
  int retval = (*__cuInit)(0);
  printf("%d", retval);
}

To test:
gcc -ldl test.c -o test
./test

I can replicate your issue. I have the same versions, same OS. What I think happened is that in my case, nvidia doesn't support my video card anymore on the current driver series. When I put a Quadro FX 580 into the nvidia driver tool, it comes back with driver version 319.17 being the latest usable driver. And in truth, the 334.21 driver does not list the Quadro FX 580 as a supported card.

This probably has something to do with it.

Same problem here with the exception of the fact that my two 9600GT cards are supported by the 331.24 driver.

Typo - I meant to say my 9600GT cards are supported by the 334.21 drivers.

I have exactly the same situation here, wondered why BOINC suddenly found no GPUs after that update.

I installed opencl-nvidia along with the nvidia update, and thought that the opencl package was the problem. Of course I removed it and it made no difference.
But yesterday I installed the opencl-nvidia package again, restarted boinc, and got this:

18-Mar-2014 13:31:58 [---] [coproc] launching child process at /usr/bin/boinc_client
18-Mar-2014 13:31:58 [---] [coproc] relative to directory /
18-Mar-2014 13:31:58 [---] [coproc] with data directory /var/lib/boinc
18-Mar-2014 13:31:58 [---] CUDA: NVIDIA GPU 0: GeForce GTX 760 (driver version unknown, CUDA version 6.0, compute capability 3.0, 2048MB, 1806MB available, 2499 GFLOPS peak)
18-Mar-2014 13:31:58 [---] OpenCL: NVIDIA GPU 0: GeForce GTX 760 (driver version 334.21, device version OpenCL 1.1 CUDA, 2048MB, 1806MB available, 2499 GFLOPS peak)
18-Mar-2014 13:31:58 [---] NVIDIA library reports 1 GPU
18-Mar-2014 13:31:58 [---] No ATI library found

And GPU tasks started running again.
Upon reboot, however, back to the original messages and no GPU found. I have tried to recreate this without success but maybe a reboot is needed somewhere in between.

Does your BOINC start automatically at boot, or do you manually start it?
The problem with the video drivers on Linux is that they can take a long time to initialize, and therefore be available for BOINC to use for detection of GPUs. Perhaps wait 5 or 10 minutes, before starting BOINC after a reboot?

---

I start BOINC manually, never had any issues before the 334.21 drivers.
If the problem was that the video drivers weren't initialized when BOINC started, would restarting BOINC detect the GPU, or do you need to do a full reboot and then wait before starting BOINC for the first time?

Restarting BOINC after some time would do the trick.

---

I start boinc manually, and even waiting an extended time after reboot to start boinc the GPUs are not detected.Shutting boinc down and re-starting it doesn't help.

Tue 25 Mar 2014 02:29:28 PM EDT |  | Starting BOINC client version 7.2.42 for x86_64-pc-linux-gnu
Tue 25 Mar 2014 02:29:28 PM EDT |  | log flags: file_xfer, sched_ops, task
Tue 25 Mar 2014 02:29:28 PM EDT |  | Libraries: libcurl/7.35.0 OpenSSL/1.0.1f zlib/1.2.8 libssh2/1.4.3
Tue 25 Mar 2014 02:29:28 PM EDT |  | Data directory: /projects/boinc
Tue 25 Mar 2014 02:29:28 PM EDT |  | No usable GPUs found
Tue 25 Mar 2014 02:29:28 PM EDT |  | Host name: janus
Tue 25 Mar 2014 02:29:28 PM EDT |  | Processor: 2 GenuineIntel Intel(R) Core(TM)2 Duo CPU     E8500  @ 3.16GHz [Family 6 Model 23 Stepping 10]
Tue 25 Mar 2014 02:29:28 PM EDT |  | Processor features: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm dtherm tpr_shadow vnmi flexpriority
Tue 25 Mar 2014 02:29:28 PM EDT |  | OS: Linux: 3.13.6-1-ARCH
Tue 25 Mar 2014 02:29:28 PM EDT |  | Memory: 3.86 GB physical, 4.00 GB virtual
Tue 25 Mar 2014 02:29:28 PM EDT |  | Disk: 19.56 GB total, 18.50 GB free
Tue 25 Mar 2014 02:29:28 PM EDT |  | Local time is UTC -4 hours
Tue 25 Mar 2014 02:29:28 PM EDT |  | VirtualBox version: WARNING: The vboxdrv kernel module is not loaded. Either there is no module
Tue 25 Mar 2014 02:29:28 PM EDT |  | Config: use all coprocessors
Tue 25 Mar 2014 02:29:28 PM EDT | Asteroids@home | URL http://asteroidsathome.net/boinc/; Computer ID 72758; resource share 100
Tue 25 Mar 2014 02:29:28 PM EDT | Enigma@Home | URL http://www.enigmaathome.net/; Computer ID 119738; resource share 100
Tue 25 Mar 2014 02:29:28 PM EDT |  | General prefs: from http://einstein.phys.uwm.edu/ (last modified 19-Mar-2013 18:35:15)
Tue 25 Mar 2014 02:29:28 PM EDT |  | Host location: none
Tue 25 Mar 2014 02:29:28 PM EDT |  | General prefs: using your defaults
Tue 25 Mar 2014 02:29:28 PM EDT |  | Reading preferences override file
Tue 25 Mar 2014 02:29:28 PM EDT |  | Preferences:
Tue 25 Mar 2014 02:29:28 PM EDT |  | max memory usage when active: 1978.43MB
Tue 25 Mar 2014 02:29:28 PM EDT |  | max memory usage when idle: 1978.43MB
Tue 25 Mar 2014 02:29:28 PM EDT |  | max disk usage: 17.50GB
Tue 25 Mar 2014 02:29:28 PM EDT |  | max download rate: 10485760 bytes/sec
Tue 25 Mar 2014 02:29:28 PM EDT |  | max upload rate: 4194304 bytes/sec
Tue 25 Mar 2014 02:29:28 PM EDT |  | (to change preferences, visit a project web site or select Preferences in the Manager)
Tue 25 Mar 2014 02:29:28 PM EDT |  | Not using a proxy
Tue 25 Mar 2014 02:29:44 PM EDT |  | Suspending network activity - user request

Hi, I confirm that there is no way to run BOINC 334.21 for now is a Beta we will see.

BOINC installed both repositories as shell directly.

I installed the driver directly or updates to Ubuntu 14.04 Kernel 3.14.0 both generic and low latency (and in 3.13.7) and only NO works on BOINC, with the rest of the system works perfectly.

I'm also seeing this running Debian Sid.. updated to the 334.21 nvidia driver & no more GPU work units. Any timeline on this being fixed?

Could you all install this as well:
ocl-icd-libopencl1

It should install libopencl.so which is required to run/detect OpenCL functionality.

---

----- Rom
BOINC Development Team, U.C. Berkeley
My Blog

Sorry Rom....

That forced a uninstall of several Nvidia installs

2014-05-03 19:41:36 startup packages remove
2014-05-03 19:41:36 status installed nvidia-cuda-toolkit:amd64 5.5.22-3
2014-05-03 19:41:36 remove nvidia-cuda-toolkit:amd64 5.5.22-3 <none>
2014-05-03 19:41:36 status half-configured nvidia-cuda-toolkit:amd64 5.5.22-3
2014-05-03 19:41:36 status half-installed nvidia-cuda-toolkit:amd64 5.5.22-3
2014-05-03 19:41:37 status config-files nvidia-cuda-toolkit:amd64 5.5.22-3
2014-05-03 19:41:37 status config-files nvidia-cuda-toolkit:amd64 5.5.22-3
2014-05-03 19:41:37 status installed nvidia-opencl-dev:amd64 5.5.22-3
2014-05-03 19:41:37 remove nvidia-opencl-dev:amd64 5.5.22-3 <none>
2014-05-03 19:41:37 status half-configured nvidia-opencl-dev:amd64 5.5.22-3
2014-05-03 19:41:37 status half-installed nvidia-opencl-dev:amd64 5.5.22-3
2014-05-03 19:41:37 status config-files nvidia-opencl-dev:amd64 5.5.22-3
2014-05-03 19:41:37 status config-files nvidia-opencl-dev:amd64 5.5.22-3
2014-05-03 19:41:37 status config-files nvidia-opencl-dev:amd64 5.5.22-3
2014-05-03 19:41:37 status not-installed nvidia-opencl-dev:amd64 <none>
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 remove nvidia-libopencl1:amd64 334.21-1 <none>
2014-05-03 19:41:37 status half-configured nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status half-installed nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status triggers-pending libc-bin:amd64 2.18-5
2014-05-03 19:41:37 status config-files nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 status config-files nvidia-libopencl1:amd64 334.21-1
2014-05-03 19:41:37 trigproc libc-bin:amd64 2.18-5 <none>
2014-05-03 19:41:37 status half-configured libc-bin:amd64 2.18-5
2014-05-03 19:41:37 status installed libc-bin:amd64 2.18-5
2014-05-03 19:41:37 startup archives unpack
2014-05-03 19:41:37 install ocl-icd-libopencl1:amd64 <none> 2.1.3-4
2014-05-03 19:41:37 status half-installed ocl-icd-libopencl1:amd64 2.1.3-4
2014-05-03 19:41:37 status triggers-pending man-db:amd64 2.6.7.1-1
2014-05-03 19:41:37 status unpacked ocl-icd-libopencl1:amd64 2.1.3-4
2014-05-03 19:41:37 status unpacked ocl-icd-libopencl1:amd64 2.1.3-4
2014-05-03 19:41:37 trigproc man-db:amd64 2.6.7.1-1 2.6.7.1-1
2014-05-03 19:41:37 status half-configured man-db:amd64 2.6.7.1-1
2014-05-03 19:41:38 status installed man-db:amd64 2.6.7.1-1
2014-05-03 19:41:38 startup packages configure
2014-05-03 19:41:38 configure ocl-icd-libopencl1:amd64 2.1.3-4 <none>
2014-05-03 19:41:38 status unpacked ocl-icd-libopencl1:amd64 2.1.3-4
2014-05-03 19:41:38 status half-configured ocl-icd-libopencl1:amd64 2.1.3-4
2014-05-03 19:41:38 status installed ocl-icd-libopencl1:amd64 2.1.3-4
2014-05-03 19:41:38 status triggers-pending libc-bin:amd64 2.18-5
2014-05-03 19:41:38 trigproc libc-bin:amd64 2.18-5 <none>
2014-05-03 19:41:38 status half-configured libc-bin:amd64 2.18-5
2014-05-03 19:41:38 status installed libc-bin:amd64 2.18-5:

And on reboot & then BOINC restart I still get:

Sat 03 May 2014 07:49:20 PM PDT | | Starting BOINC client version 7.2.42 for x86_64-pc-linux-gnu
Sat 03 May 2014 07:49:20 PM PDT | | log flags: file_xfer, sched_ops, task
Sat 03 May 2014 07:49:20 PM PDT | | Libraries: libcurl/7.36.0 OpenSSL/1.0.2 zlib/1.2.8 libidn/1.28 libssh2/1.4.3
Sat 03 May 2014 07:49:20 PM PDT | | Data directory: /home/dean/BOINC
Sat 03 May 2014 07:49:20 PM PDT | | No usable GPUs found
Sat 03 May 2014 07:49:20 PM PDT | | Host name: linux

Suggestions?

In hunting for the library I found something "interesting"---are you looking for libopencl.so or libOpenCL.so??

In my system the file Nvidia put in was located in /usr/lib/x86_64-linux-gnu & was named libOpenCL.so. I have made a link to the library that uses all lower case & am going to restart...will post back with findings.

Update: reboot & then BOINC restart...still no GPUs found

Other ideas?