From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Tue, 16 Jun 2020 12:04:52 +0000 (+0200)
Subject: 4.9-stable patches
X-Git-Tag: v5.4.47~29
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5b79a9eaa0f116abd37fec87c57ab8fa555f867a;p=thirdparty%2Fkernel%2Fstable-queue.git

4.9-stable patches

added patches:
	agp-intel-reinforce-the-barrier-after-gtt-updates.patch
---

diff --git a/queue-4.9/agp-intel-reinforce-the-barrier-after-gtt-updates.patch b/queue-4.9/agp-intel-reinforce-the-barrier-after-gtt-updates.patch
new file mode 100644
index 00000000000..6623609cc72
--- /dev/null
+++ b/queue-4.9/agp-intel-reinforce-the-barrier-after-gtt-updates.patch
@@ -0,0 +1,55 @@
+From f30d3ced9fafa03e4855508929b5b6334907f45e Mon Sep 17 00:00:00 2001
+From: Chris Wilson <chris@chris-wilson.co.uk>
+Date: Fri, 10 Apr 2020 09:35:35 +0100
+Subject: agp/intel: Reinforce the barrier after GTT updates
+
+From: Chris Wilson <chris@chris-wilson.co.uk>
+
+commit f30d3ced9fafa03e4855508929b5b6334907f45e upstream.
+
+After changing the timing between GTT updates and execution on the GPU,
+we started seeing sporadic failures on Ironlake. These were narrowed
+down to being an insufficiently strong enough barrier/delay after
+updating the GTT and scheduling execution on the GPU. By forcing the
+uncached read, and adding the missing barrier for the singular
+insert_page (relocation paths), the sporadic failures go away.
+
+Fixes: 983d308cb8f6 ("agp/intel: Serialise after GTT updates")
+Fixes: 3497971a71d8 ("agp/intel: Flush chipset writes after updating a single PTE")
+Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
+Acked-by: Andi Shyti <andi.shyti@intel.com>
+Cc: stable@vger.kernel.org # v4.0+
+Link: https://patchwork.freedesktop.org/patch/msgid/20200410083535.25464-1-chris@chris-wilson.co.uk
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/char/agp/intel-gtt.c |    4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+--- a/drivers/char/agp/intel-gtt.c
++++ b/drivers/char/agp/intel-gtt.c
+@@ -845,6 +845,7 @@ void intel_gtt_insert_page(dma_addr_t ad
+ 			   unsigned int flags)
+ {
+ 	intel_private.driver->write_entry(addr, pg, flags);
++	readl(intel_private.gtt + pg);
+ 	if (intel_private.driver->chipset_flush)
+ 		intel_private.driver->chipset_flush();
+ }
+@@ -870,7 +871,7 @@ void intel_gtt_insert_sg_entries(struct
+ 			j++;
+ 		}
+ 	}
+-	wmb();
++	readl(intel_private.gtt + j - 1);
+ 	if (intel_private.driver->chipset_flush)
+ 		intel_private.driver->chipset_flush();
+ }
+@@ -1104,6 +1105,7 @@ static void i9xx_cleanup(void)
+ 
+ static void i9xx_chipset_flush(void)
+ {
++	wmb();
+ 	if (intel_private.i9xx_flush_page)
+ 		writel(1, intel_private.i9xx_flush_page);
+ }
diff --git a/queue-4.9/series b/queue-4.9/series
index 32737ddf085..c889403973c 100644
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -48,3 +48,4 @@ smack-slab-out-of-bounds-in-vsscanf.patch
 mm-slub-fix-a-memory-leak-in-sysfs_slab_add.patch
 fat-don-t-allow-to-mount-if-the-fat-length-0.patch
 perf-add-cond_resched-to-task_function_call.patch
+agp-intel-reinforce-the-barrier-after-gtt-updates.patch