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From ee65925972007b373c20a4c44ddfb1d6ab6de197 Mon Sep 17 00:00:00 2001
From: James Jones <jajones@nvidia.com>
Date: Mon, 16 Dec 2019 16:56:12 -0800
Subject: drm/nouveau: Fix ttm move init with multiple GPUs
Git-commit: 72ecb0a6ce89dd7f9d0f8171a45b0ed814b0f9a8
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322

The pointer used to walk the table of move ops
and pick the right one for the current GPU was
declared static, meaning its state was carried
over between invocations of the function, and also
made the function non-rentrant and thread-unsafe.
Since the table is ordered such that newer GPU
methods are listed first, the result of this was
that initializing newer GPUs after older GPUs
would result in no suitable ttm move acceleration
operations being found, and ttm would fall back
to CPU blits on the older GPUs.

This change declares the walking pointer
separately from the table and makes it non-static
to fix the logic.

Signed-off-by: James Jones <jajones@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/nouveau/nouveau_bo.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index f8015e0318d7..1b62ccc57aef 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -1162,7 +1162,7 @@ nouveau_bo_move_m2mf(struct ttm_buffer_object *bo, int evict, bool intr,
 void
 nouveau_bo_move_init(struct nouveau_drm *drm)
 {
-	static const struct {
+	static const struct _method_table {
 		const char *name;
 		int engine;
 		s32 oclass;
@@ -1192,7 +1192,8 @@ nouveau_bo_move_init(struct nouveau_drm *drm)
 		{  "M2MF", 0, 0x0039, nv04_bo_move_m2mf, nv04_bo_move_init },
 		{},
 		{ "CRYPT", 0, 0x88b4, nv98_bo_move_exec, nv50_bo_move_init },
-	}, *mthd = _methods;
+	};
+	const struct _method_table *mthd = _methods;
 	const char *name = "CPU";
 	int ret;
 
-- 
2.28.0