This is a note to let you know that I've just added the patch titled

    drm/i915: Prevent MI_DISPLAY_FLIP straddling two cachelines on IVB

to the 3.13-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-i915-prevent-mi_display_flip-straddling-two-cachelines-on-ivb.patch
and it can be found in the queue-3.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From f66fab8e1cd6b3127ba4c5c0d11539fbe1de1e36 Mon Sep 17 00:00:00 2001
From: Ville Syrjälä <[email protected]>
Date: Tue, 11 Feb 2014 19:52:06 +0200
Subject: drm/i915: Prevent MI_DISPLAY_FLIP straddling two cachelines on IVB
MIME-Version: 1.0
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From: Ville Syrjälä <[email protected]>

commit f66fab8e1cd6b3127ba4c5c0d11539fbe1de1e36 upstream.

According to BSpec the entire MI_DISPLAY_FLIP packet must be contained
in a single cacheline. Make sure that happens.

v2: Use intel_ring_begin_cacheline_safe()
v3: Use intel_ring_cacheline_align() (Chris)

Cc: Bjoern C <[email protected]>
Cc: Alexandru DAMIAN <[email protected]>
Cc: Enrico Tagliavini <[email protected]>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=74053
Signed-off-by: Ville Syrjälä <[email protected]>
Cc: [email protected]
Signed-off-by: Daniel Vetter <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/gpu/drm/i915/intel_display.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8335,6 +8335,20 @@ static int intel_gen7_queue_flip(struct
        if (ring->id == RCS)
                len += 6;
 
+       /*
+        * BSpec MI_DISPLAY_FLIP for IVB:
+        * "The full packet must be contained within the same cache line."
+        *
+        * Currently the LRI+SRM+MI_DISPLAY_FLIP all fit within the same
+        * cacheline, if we ever start emitting more commands before
+        * the MI_DISPLAY_FLIP we may need to first emit everything else,
+        * then do the cacheline alignment, and finally emit the
+        * MI_DISPLAY_FLIP.
+        */
+       ret = intel_ring_cacheline_align(ring);
+       if (ret)
+               goto err_unpin;
+
        ret = intel_ring_begin(ring, len);
        if (ret)
                goto err_unpin;


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.13/drm-i915-add-intel_ring_cachline_align.patch
queue-3.13/drm-i915-prevent-mi_display_flip-straddling-two-cachelines-on-ivb.patch
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