mshv: Initialize local variables early upon region invalidation

Ensure local variables are initialized before use so that the warning can
print the right values if locking the region to invalidate fails due to
inability to lock the region.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: b9a66cd ("mshv: Add support for movable memory regions")
Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Signed-off-by: Wei Liu <wei.liu@kernel.org>

Author: Stanislav Kinsburskii

drivers/hv/mshv_regions.c

@@ -494,20 +494,20 @@ static bool mshv_region_interval_invalidate(struct mmu_interval_notifier *mni,
 	unsigned long mstart, mend;
 	int ret = -EPERM;
 
-	if (mmu_notifier_range_blockable(range))
-		mutex_lock(&region->mutex);
-	else if (!mutex_trylock(&region->mutex))
-		goto out_fail;
-
-	mmu_interval_set_seq(mni, cur_seq);
-
 	mstart = max(range->start, region->start_uaddr);
 	mend = min(range->end, region->start_uaddr +
 		   (region->nr_pages << HV_HYP_PAGE_SHIFT));
 
 	page_offset = HVPFN_DOWN(mstart - region->start_uaddr);
 	page_count = HVPFN_DOWN(mend - mstart);
 
+	if (mmu_notifier_range_blockable(range))
+		mutex_lock(&region->mutex);
+	else if (!mutex_trylock(&region->mutex))
+		goto out_fail;
+
+	mmu_interval_set_seq(mni, cur_seq);
+
 	ret = mshv_region_remap_pages(region, HV_MAP_GPA_NO_ACCESS,
 				      page_offset, page_count);
 	if (ret)