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      <base href="https://bugs.freedesktop.org/">
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - src/intel_device.c reverses return value meaning of xorg server xf86LoadKernelModule()"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=100011">100011</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>src/intel_device.c reverses return value meaning of xorg server xf86LoadKernelModule()
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>xorg
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>git
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Other
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>FreeBSD
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Driver/intel
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>chris@chris-wilson.co.uk
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>davshao@gmail.com
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-gfx-bugs@lists.freedesktop.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>The function load_i915_kernel_module() in file src/intel_device.c
of xf86-video-intel reverses the meaning of the return value of
xorg server's xf86LoadKernelModule().  xf86LoadKernelModule()
actually returns 0 if the loading fails, non-zero if success.

For example, from xorg server 1.19.1's source code,
file hw/xfree86/os-support/linux/lnx_kmod.c:

 * Input:
 *    modName - name of the kernel module (Ex: "tdfx")
 * Return:
 *    0 for failure, 1 for success
 */
int
xf86LoadKernelModule(const char *modName)

        if (WIFEXITED(status) && WEXITSTATUS(status) == 0) {
            return 1;           /* success! */
        }
        else {
            return 0;
        }

And from file hw/xfree86/os-support/bsd/bsd_kmod.c

 * Return:
 *    0 for failure, 1 for success
 */
int
xf86LoadKernelModule(const char *modName)
{
    if (kldload(modName) != -1)
        return 1;
    else
        return 0;
}

On FreeBSD there is an additional complication that if
"i915kms" is added to kernel_module_names, the inverted use
of the return value causes both i915kms.ko and i915.ko to
be loaded.

Therefore I believe a patch similar to the following needs to be made
to src/intel_device.c:

@@ -233,9 +242,8 @@ static int load_i915_kernel_module(void)
        const char **kn;

        for (kn = kernel_module_names; *kn; kn++)
-               if (xf86LoadKernelModule(*kn) == 0)
+               if (xf86LoadKernelModule(*kn))
                        return 0;
-
        return -1;
 }</pre>
        </div>
      </p>


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