kmem_cache_free() frees *workload*, hence there is a use-after-free bug
when calling function gvt_vgpu_err().

Fix this by storing the value of workload->wa_ctx.indirect_ctx.guest_gma
and workload->wa_ctx.per_ctx.guest_gma into automatic variable
guest_gma before freeing *workload*, for its further use.

Addresses-Coverity-ID: 1452235 ("Read from pointer after free")
Fixes: 2089a76ade90 ("drm/i915/gvt: Checking workload's gma earlier")
Signed-off-by: Gustavo A. R. Silva <gust...@embeddedor.com>
---
 drivers/gpu/drm/i915/gvt/scheduler.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/scheduler.c 
b/drivers/gpu/drm/i915/gvt/scheduler.c
index 32ae6b5b7e16..c8cdb4a309f6 100644
--- a/drivers/gpu/drm/i915/gvt/scheduler.c
+++ b/drivers/gpu/drm/i915/gvt/scheduler.c
@@ -1525,9 +1525,11 @@ intel_vgpu_create_workload(struct intel_vgpu *vgpu, int 
ring_id,
                        if (!intel_gvt_ggtt_validate_range(vgpu,
                                workload->wa_ctx.indirect_ctx.guest_gma,
                                workload->wa_ctx.indirect_ctx.size)) {
+                               unsigned long guest_gma =
+                                      workload->wa_ctx.indirect_ctx.guest_gma;
                                kmem_cache_free(s->workloads, workload);
                                gvt_vgpu_err("invalid wa_ctx at: 0x%lx\n",
-                                   workload->wa_ctx.indirect_ctx.guest_gma);
+                                            guest_gma);
                                return ERR_PTR(-EINVAL);
                        }
                }
@@ -1539,9 +1541,11 @@ intel_vgpu_create_workload(struct intel_vgpu *vgpu, int 
ring_id,
                        if (!intel_gvt_ggtt_validate_range(vgpu,
                                workload->wa_ctx.per_ctx.guest_gma,
                                CACHELINE_BYTES)) {
+                               unsigned long guest_gma =
+                                       workload->wa_ctx.per_ctx.guest_gma;
                                kmem_cache_free(s->workloads, workload);
                                gvt_vgpu_err("invalid per_ctx at: 0x%lx\n",
-                                       workload->wa_ctx.per_ctx.guest_gma);
+                                            guest_gma);
                                return ERR_PTR(-EINVAL);
                        }
                }
-- 
2.22.0

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