https://bugzilla.novell.com/show_bug.cgi?id=818561 https://bugzilla.novell.com/show_bug.cgi?id=818561#c0 Summary: Unreadable screen (color bars) on i915 Graphics Controller with VT-d on. Classification: openSUSE Product: openSUSE 12.3 Version: Final Platform: x86-64 OS/Version: openSUSE 12.3 Status: NEW Severity: Major Priority: P5 - None Component: Kernel AssignedTo: kernel-maintainers@forge.provo.novell.com ReportedBy: gadm@avalon-island.ru QAContact: qa-bugs@suse.de Found By: --- Blocker: --- User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:20.0) Gecko/20100101 Firefox/20.0 Analysis of the 'dmesg' output running Linux kernel without Xen but with IOMMU on shows the following diagnostics: [ 0.243871] dmar: DRHD: handling fault status reg 3 [ 0.243878] dmar: DMAR:[DMA Write] Request device [00:02.0] fault addr bf800000 [ 0.243878] DMAR:[fault reason 01] Present bit in root entry is clear [ 0.243926] PCI-DMA: Intel(R) Virtualization Technology for Directed I/O Device 00:02.0 is, obviously, graphics controller. Although Linux+VT-d doesn't lock up hard, screen is completely unreadable (color bars). Reproducible: Always Steps to Reproduce: 1. Install openSUSE 12.3 on 82Q35 Desktop platform 2. Prepare GRUB entry with kernel parameter 'intel_iommu=on' 3. Boot Actual Results: Garbage on main screen (color bars) -- but system is not locked up (for example, serial console and Serial-over-LAN console work). Expected Results: Working video subsystem Developers claim that this bug can be root cause of this one -- https://bugzilla.novell.com/show_bug.cgi?id=817210 -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.