Hide Forgot
Description of problem: On HP ELiteBook 2540p with Intel Ironlake Graphics, the drm rebased uncovered a bug in the IOMMU hardware. This causes the panic unless graphics passthrough is enabled. Version-Release number of selected component (if applicable): How reproducible: Run for a few hours with a kernel build in a terminal Plan is get Intel to fix or if not just disable IOMMU for graphics device for G4x and Ironlake.
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
Better reproducer, Get a ILK laptop that supports VT-d properly, HP Elitebook 2540p, not a lot of Lenovo ILK fail to enable graphics VT-d due to a bios bug. Use desktop effects to enable compiz, open a gnome-terminal run while [ 1 == 1 ]; do find . ; done Leave running as long as possible, eventually machine will hang.
oh you have to enable VT-d in the BIOS and boot EL6.2 kernels with intel_iommu=on
If the Ironlake can enable VT-D and if VT-d works on it. Some BIOSes mess up, you'll see DMAR: BIOS has allocated no shadow GTT; disabling IOMMU for graphics in dmesg, reproducing on these is also difficult (if possible at all).
Patch(es) available on kernel-2.6.32-212.el6
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHSA-2011-1530.html