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<p class="MsoNormal"><span style="color:#002060">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">I recently asked if the ICH9 chipset must be used with virtual devices which require MSI interrupt support, and learned that yes it is required. The PIIX3 chipset does not support MSI. (see attached)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">So I have migrated to a new VM that uses ICH9 chipset, but have found I still have the same MSI problem as with PIIX3.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">When VBox or BIOS sets up the MSI structure in the extended PCI config space of my virtual device, it sets the address field to fee0100c (upper=0). However, that does not appear to be within any mapped address
range — the closest thing is APIC, in the range fee00000 to fee00fff.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">So when my device tries to raise an interrupt by DMA writing to fee0100c, VBox cannot find an address range, so the write never actually happens. Therefore no interrupt happens, so the device cannot work correctly.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">Is there some other bit of VM configuration that I must do for MSI support? I noticed in the logs that LAPIC is disabled, so I wonder if my VM is just missing something.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">Log files are attached, pruned to meet the 100k email limit (original available upon request). Lines bearing the “RicV” prefix were instrumented by me while troubleshooting. Lines bearing the “RemDev” prefix
are coming from my PDM plug-in. I also inserted C-style comments at the point interesting points.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">Environment: VBox 5.0.16 built from OSE tarball on the downloads page, running on Ubuntu 14 host, with Ubuntu 14 guest.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">_____________________________________________<o:p></o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;color:#002060"><o:p> </o:p></span></b></p>
<p class="MsoNormal"><b><span style="color:#002060">Ric Vilbig</span></b><span style="color:#002060"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#002060">Mentor Graphics, Emulation Division<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#002060">46871 Bayside Parkway, Fremont CA, 94538<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#002060">Phone: 510-354-7360<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#002060">Mobile: 408-529-2365<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#002060">email: <a href="mailto:ric_vilbig@mentor.com">
ric_vilbig@mentor.com</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;color:#002060"><o:p> </o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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