On Wed, 15 Feb 2017, Jani Nikula <[email protected]> wrote: > On Tue, 14 Feb 2017, Daniel Vetter <[email protected]> wrote: >> On Tue, Feb 14, 2017 at 02:49:21PM +0200, Jani Nikula wrote: >>> From: Pierre-Louis Bossart <[email protected]> >>> >>> 100% reproducible issue found on SKL SkullCanyon NUC with two external >>> DP daisy-chained monitors in DP/MST mode. When turning off or changing >>> the input of the second monitor the machine stops with a kernel >>> oops. This issue happened with 4.8.8 as well as drm/drm-intel-nightly. >>> >>> This issue is traced to an inconsistent control flow in >>> drm_dp_update_payload_part1(): the 'port' pointer is set to NULL at the >>> same time as 'req_payload.num_slots' is set to zero, but the pointer is >>> dereferenced even when req_payload.num_slot is zero. >>> >>> The problematic dereference was introduced in commit dfda0df34 >>> ("drm/mst: rework payload table allocation to conform better") and may >>> impact all versions since v3.18 >>> >>> The fix suggested by Chris Wilson removes the kernel oops and was found to >>> work well after 10mn of monkey-testing with the second monitor power and >>> input buttons >>> >>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98990 >>> Fixes: dfda0df34264 ("drm/mst: rework payload table allocation to conform >>> better.") >>> Cc: Dave Airlie <[email protected]> >>> Cc: Chris Wilson <[email protected]> >>> Cc: Nathan D Ciobanu <[email protected]> >>> Cc: Dhinakaran Pandiyan <[email protected]> >>> Cc: Sean Paul <[email protected]> >>> Cc: <[email protected]> # v3.18+ >>> Tested-by: Nathan D Ciobanu <[email protected]> >>> Reviewed-by: Dhinakaran Pandiyan <[email protected]> >>> Signed-off-by: Pierre-Louis Bossart <[email protected]> >>> Signed-off-by: Jani Nikula <[email protected]> >> >> You haz drm-misc commit rights, pls use them :-) > > Sure, I just wanted to have a fresh CI run on this. > >> Since it doesn't have deps, probably simplest to smash into drm-misc-fixes >> and then send a pull req to Dave right away. If you want, you can roll >> -fixes forward to -rc8 while at it. > > Will do.
And pushed to drm-misc-fixes, thanks for the patch, review and testing. BR, Jani. -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ dri-devel mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/dri-devel
