<html><body><div style="font-family: Andale Mono; font-size: 12pt; color: #666666"><div><div>Dear George,<br data-mce-bogus="1"></div><div>Thanks for the input and ideas.<br data-mce-bogus="1"></div><div>Unfortunately bootscrub=false dos not work, not does setting nothing for vga, still get the 'Little white squares'!<br></div><div>I am asking the xen-users as you suggest<br></div><div>Regards, Francis<br></div></div><div><br></div><hr id="zwchr" data-marker="__DIVIDER__"><div data-marker="__HEADERS__"><b>From: </b>"George Dunlap" <dunlapg@umich.edu><br><b>To: </b>"Francis Greaves" <francis@choughs.net>, "centos-virt" <centos-virt@centos.org><br><b>Sent: </b>Tuesday, 23 February, 2016 09:31:40<br><b>Subject: </b>Re: [CentOS-virt] Garbled screen after RAM Scrub on boot<br></div><br><div data-marker="__QUOTED_TEXT__">On Mon, Feb 22, 2016 at 4:18 PM, Francis Greaves <francis@choughs.net> wrote:<br>> Dear All<br>> I am using Centos 7 with Xen 4.6 on a Dell Poweredge T430<br>> When the machine boots, after the 'Scrubbing Free RAM' message, I get a<br>> screen filled with little white squares until the login prompt, so I cannot<br>> see what is happening as the machine boots. Also there is nothing on the<br>> screen when I reboot.<br>><br>> My /etc/default/grub is<br>><br>> GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"<br>> GRUB_DEFAULT=saved<br>> GRUB_DISABLE_SUBMENU=true<br>> GRUB_CMDLINE_LINUX="crashkernel=auto rhgb intremap=no_x2apic_optout"<br>> GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=13312M,max:14336M dom0_max_vcpus=6<br>> dom0_vcpus_pin"<br>> GRUB_GFXMODE=1024x768<br>> GRUB_GFXPAYLOAD_LINUX=keep<br>> GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen<br>> nomodeset"<br>><br>> I have tried setting (for a 1024x768 resolution) vga=792 in the<br>> GRUB_CMDLINE_LINUX and commenting out GRUB_GFXMODE and<br>> GRUB_GFXPAYLOAD_LINUX, but this makes no difference<br>><br>> What am I doing wrong?<br><br>Francis,<br><br>Thanks for reporting this. I'd suggest re-posting your question on<br>xen-users -- there are a lot more eyeballs watching that list than<br>this one, and it's easier to "escalate" the issue to the development<br>list from there.<br><br>My first instinct is wondering whether grub setting the graphics mode<br>is part of the problem. Have you tried having grub just take the bios<br>text mode that was given it, rather than changing it?<br><br>(Obviously ideally Xen would work whatever the graphics mode is, but<br>most developers are accessing test boxes over serial in a colo, so<br>it's not the kind of thing they're prone to notice.)<br><br> -George<br></div></div></body></html>