Bug 15212

Summary:	DRI can't be enabled on ia64 systems
Product:	Drivers	Reporter:	Émeric Maschino (emeric.maschino)
Component:	Video(DRI - non Intel)	Assignee:	drivers_video-dri
Status:	CLOSED CODE_FIX
Severity:	high	CC:	akpm, alan, max
Priority:	P1
Hardware:	All
OS:	Linux
Kernel Version:	2.6.30 and following	Subsystem:
Regression:	Yes	Bisected commit-id:

Description Émeric Maschino 2010-02-02 20:55:23 UTC

Hi,

I've been asked at http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=546655#51 to file a bug report about this issue, so please find it below.

With Linux kernel 2.6.30 and above, DRI can't be enabled on ia64 systems. Additionally, dmesg reports (with drm.debug=1 passed to kernel):

[   23.807789] [drm] Initialized drm 1.1.0 20060810
[   23.821636] [drm] Initialized radeon 1.30.0 20080528 for 0000:80:00.0 on
minor 0
[   24.137421] [drm:drm_mmap_locked] *ERROR* Could not find map

I've found this bug during kernel 2.6.33 development cycle. Last working kernel was 2.6.29. I've bisected this regression to commit f1a2a9b6189f9f5c27672d4d32fec9492c6486b2 (drm: Preserve SHMLBA bits in hash key for _DRM_SHM mappings) during kernel 2.6.30 development cycle.

Simply reverting this patch from current kernel source (2.6.33-rc6 as time of writing) enables back DRI on ia64 systems. Since this is a generic patch, I've asked several times the author (David Miller <davem@davemloft.net>) for help through the linux-ia64 list and by email. Still no answer at this time.

Cheers,

Émeric

Comment 1 Andrew Morton 2010-02-03 22:27:16 UTC

Thanks, I'll reassign this regression to DRI.

Comment 2 Alan 2012-06-18 14:45:17 UTC

See also http://marc.info/?l=linux-ia64&m=130263778331960&w=2