From 0f43702a334b2848ae2e942dbc0677ddc4566b57 Mon Sep 17 00:00:00 2001
From: fred gao <fred.gao@intel.com>
Date: Fri, 18 Aug 2017 15:41:10 +0800
Subject: [PATCH] drm/i915/gvt: Refine error handling in dispatch_workload
Git-commit: 0f43702a334b2848ae2e942dbc0677ddc4566b57
Patch-mainline: v4.15-rc1
References: FATE#322643 bsc#1055900

When an error occurs in dispatch_workload, this patch is to do the
proper cleanup and rollback to the original states before the workload
is abandoned.

V2: 
- split the mixed several error paths for better review. (Zhenyu)

V3: 
- original PTR_ERR(cs) is good and code cleanup. (Zhenyu)

V4: 
- reuse the existing i915_add_request for error handling. (Zhenyu)

V5: 
- remove the duplicate error handling release_shadow_wa_ctx and
  move the engine->context_unpin upper. (Zhenyu)

V6: 
- keep the old label "out". (Zhenyu)

Signed-off-by: fred gao <fred.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/gvt/scheduler.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -342,8 +342,10 @@ static int dispatch_workload(struct inte
 
 	if (workload->prepare) {
 		ret = workload->prepare(workload);
-		if (ret)
+		if (ret) {
+			engine->context_unpin(engine, shadow_ctx);
 			goto out;
+		}
 	}
 
 out: