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<p class="MsoNormal">When we build a Centos 7 VM with 1.4T RAM it fails with “[ 17.797177] BUG: unable to handle kernel paging request at ffff988b19478000”<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I asked in #centos and they asked me to show a list of devices from a working VM (if I use 720G RAM it works). This is the list:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[root@alberttest1 ~]# lspci<o:p></o:p></p>
<p class="MsoNormal">00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)<o:p></o:p></p>
<p class="MsoNormal">00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]<o:p></o:p></p>
<p class="MsoNormal">00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II]<o:p></o:p></p>
<p class="MsoNormal">00:01.2 USB controller: Intel Corporation 82371SB PIIX3 USB [Natoma/Triton II] (rev 01)<o:p></o:p></p>
<p class="MsoNormal">00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03)<o:p></o:p></p>
<p class="MsoNormal">00:02.0 VGA compatible controller: Cirrus Logic GD 5446<o:p></o:p></p>
<p class="MsoNormal">00:03.0 Ethernet controller: Red Hat, Inc. Virtio network device<o:p></o:p></p>
<p class="MsoNormal">00:04.0 SCSI storage controller: Red Hat, Inc. Virtio block device<o:p></o:p></p>
<p class="MsoNormal">00:05.0 SCSI storage controller: Red Hat, Inc. Virtio block device<o:p></o:p></p>
<p class="MsoNormal">00:06.0 SCSI storage controller: Red Hat, Inc. Virtio block device<o:p></o:p></p>
<p class="MsoNormal">00:07.0 Unclassified device [00ff]: Red Hat, Inc. Virtio memory balloon<o:p></o:p></p>
<p class="MsoNormal">[root@alberttest1 ~]# lsusb<o:p></o:p></p>
<p class="MsoNormal">Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd<o:p></o:p></p>
<p class="MsoNormal">Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">They suspect that the “Virtio memory balloon” driver is causing the problem, and that we should disable it. I googled around and found this:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">http://www.linux-kvm.org/page/Projects/auto-ballooning<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It looks like memory ballooning is deprecated. How can I get rid of the driver?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Also they complained about my host bridge device; they say that we should have a newer one:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Where can I specify the host bridge?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><bugs_> ok ozzzo one of the devices is called "virtio memory balloon"<o:p></o:p></p>
<p class="MsoNormal">[13:18:12] <bugs_> do you see that?<o:p></o:p></p>
<p class="MsoNormal">[13:18:21] <ozzzo> yes<o:p></o:p></p>
<p class="MsoNormal">[13:18:47] <bugs_> i suggest you google that and read about what it does - i think it would<o:p></o:p></p>
<p class="MsoNormal">[13:19:02] <bugs_> be worth trying to disable that device on your larger vm to see what happens<o:p></o:p></p>
<p class="MsoNormal">[13:19:18] <ozzzo> ok I will try that, thank you<o:p></o:p></p>
<p class="MsoNormal">[13:19:30] * Altiare (~Altiare@unaffiliated/altiare) has quit IRC (Quit: Leaving)<o:p></o:p></p>
<p class="MsoNormal">[13:21:45] * Sheogorath[m] (sheogora1@gateway/shell/matrix.org/x-uiiwpoddodtgrwwz) joins #centos<o:p></o:p></p>
<p class="MsoNormal">[13:22:06] <@TrevorH> I also notice that the VM seems to be using the very old 440FX and there's a newer model of hardware available that might be worth checking<o:p></o:p></p>
<p class="MsoNormal">[13:22:21] <@TrevorH> 440FX chipset is the old old pentium Pro chipset!<o:p></o:p></p>
<p class="MsoNormal">[13:22:32] <@TrevorH> I had one of those in about 1996<o:p></o:p></p>
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