Bug 107840

Summary:	Framebuffer: Driver reports wrong max dimensions
Product:	xorg	Reporter:	Kristian Robertsen <kristian.robertsen>
Component:	Driver/modesetting	Assignee:	Xorg Project Team <xorg-team>
Status:	RESOLVED DUPLICATE	QA Contact:	Xorg Project Team <xorg-team>
Severity:	major
Priority:	medium	CC:	intel-gfx-bugs
Version:	unspecified
Hardware:	All
OS:	Linux (All)
URL:	https://cgit.freedesktop.org/drm-tip/tree/drivers/gpu/drm/i915/intel_display.c#n15234
Whiteboard:
i915 platform:		i915 features:

Description Kristian Robertsen 2018-09-05 12:46:14 UTC

The driver reports wrong maximum framebuffer dimensions for newer generation GPUs. 

While (at least) 7th gen and up support 16384x16384 the driver reports 8192x8192 for any 4th gen GPU or higher.

Causes display servers to crash with ultrawide and 4K monitors.

Comment 1 Chris Wilson 2018-09-05 13:03:10 UTC

What the kernel reports is the maximum of an individual pipe. That -modesetting cannot stitch together per-crtc pixmaps to overcome HW limitations is a functional regression in switching to -modesetting. There are different ways to overcome that, Ville has a plan to transparently hide the limitation, the one advantage to handling it inside userspace (where it has been done previously) is that it just works against any kernel and device.

Comment 2 Daniel van Vugt 2018-09-06 02:18:14 UTC

Duplicate of bug 102508 ?

Comment 3 Daniel van Vugt 2018-09-06 02:18:38 UTC


*** This bug has been marked as a duplicate of bug 102508 ***

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