[Intel-gfx] [PATCH] drm/i915/gtt: Correct unshifted 'from' for gen8_ppgtt_alloc errors

[Chris Wilson]

Since the underlying __gen8_ppgtt_clear takes the shifted address, we
must remember to provide it with the preshifted original start address.

Reported-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Cc: Abdiel Janulgue <abdiel.janulgue at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem_gtt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 220aba5a94d2..031bcd22f5e6 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -1103,7 +1103,7 @@ static int __gen8_ppgtt_alloc(struct i915_address_space * const vm,
 static int gen8_ppgtt_alloc(struct i915_address_space *vm,
 			    u64 start, u64 length)
 {
-	u64 from = start;
+	u64 from;
 	int err;
 
 	GEM_BUG_ON(!IS_ALIGNED(start, BIT_ULL(GEN8_PTE_SHIFT)));
@@ -1112,6 +1112,7 @@ static int gen8_ppgtt_alloc(struct i915_address_space *vm,
 	start >>= GEN8_PTE_SHIFT;
 	length >>= GEN8_PTE_SHIFT;
 	GEM_BUG_ON(length == 0);
+	from = start;
 
 	err = __gen8_ppgtt_alloc(vm, i915_vm_to_ppgtt(vm)->pd,
 				 &start, start + length, vm->top);
-- 
2.22.0