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    <body><span class="vcard"><a class="email" href="mailto:janpieter.sollie@dommel.be" title="Janpieter Sollie <janpieter.sollie@dommel.be>"> <span class="fn">Janpieter Sollie</span></a>
</span> changed
          <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - clEnqueueReadBuffer VM_PAGE FAULT"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=102179">bug 102179</a>
          <br>
             <table border="1" cellspacing="0" cellpadding="8">
          <tr>
            <th>What</th>
            <th>Removed</th>
            <th>Added</th>
          </tr>

         <tr>
           <td style="text-align:right;">Severity</td>
           <td>normal
           </td>
           <td>major
           </td>
         </tr></table>
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            <b><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - clEnqueueReadBuffer VM_PAGE FAULT"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=102179#c3">Comment # 3</a>
              on <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - clEnqueueReadBuffer VM_PAGE FAULT"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=102179">bug 102179</a>
              from <span class="vcard"><a class="email" href="mailto:janpieter.sollie@dommel.be" title="Janpieter Sollie <janpieter.sollie@dommel.be>"> <span class="fn">Janpieter Sollie</span></a>
</span></b>
        <pre>interesting note:
the following code allows me to execute the clEnqueueReadBuffer:
//set kernel arguments, limited to 1
    clSetKernelArg ( devdb[nr_of_devices].kernel, 0,
sizeof(devdb[nr_of_devices].output), &devdb[nr_of_devices].output);

//run kernel
clEnqueueNDRangeKernel(..)
//read buffer
clEnqueueReadBuffer (((device*)device_obj)->command_queue,
((device*)device_obj)->output, CL_FALSE, 0, 16,
((device*)device_obj)->host_output, 0, NULL, NULL);

while it does not work with any 2nd, 3rd, ... kernel parameter, eg:
clSetKernelArg ( devdb[nr_of_devices].kernel, 0,
sizeof(devdb[nr_of_devices].output), &devdb[nr_of_devices].output);
clSetKernelArg ( devdb[nr_of_devices].kernel, 1,
sizeof(devdb[nr_of_devices].output2), &devdb[nr_of_devices].output2);

hangs at reading output. but no warning of VM_PAGE_FAULTS, these occur when
output is the last argument

because I think this is a blocker for most OpenCL users to get their data back,
I'm increasing it to major (also, this cannot be analyzed easily: every time
the call hangs, I have to reboot my pc, as the process becomes a zombie)</pre>
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