mshv: release mutex on region invalidation failure

In the region invalidation failure path in
mshv_region_interval_invalidate(), the region mutex is not released. Fix
it by releasing the mutex in the failure path.

Signed-off-by: Anirudh Rayabharam (Microsoft) <anirudh@anirudhrb.com>
Fixes: b9a66cd ("mshv: Add support for movable memory regions")
Acked-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
Reviewed-by: Roman Kisel <vdso@mailbox.org>
Signed-off-by: Wei Liu <wei.liu@kernel.org>

Author: Anirudh Rayabharam (Microsoft)

drivers/hv/mshv_regions.c

@@ -511,14 +511,16 @@ static bool mshv_region_interval_invalidate(struct mmu_interval_notifier *mni,
 	ret = mshv_region_remap_pages(region, HV_MAP_GPA_NO_ACCESS,
 				      page_offset, page_count);
 	if (ret)
-		goto out_fail;
+		goto out_unlock;
 
 	mshv_region_invalidate_pages(region, page_offset, page_count);
 
 	mutex_unlock(&region->mutex);
 
 	return true;
 
+out_unlock:
+	mutex_unlock(&region->mutex);
 out_fail:
 	WARN_ONCE(ret,
 		  "Failed to invalidate region %#llx-%#llx (range %#lx-%#lx, event: %u, pages %#llx-%#llx, mm: %#llx): %d\n",