From 6fa411adff39e4955f11aa3e854a876680444d2a Mon Sep 17 00:00:00 2001
From: Qiang Liu <liuqiang@kylinos.cn>
Date: Fri, 15 May 2026 15:03:11 +0800
Subject: [PATCH] lib/test_hmm: fix error path in dmirror_devmem_fault()

Handle migrate_vma_setup() failure via goto err for unified cleanup.

Link: https://lore.kernel.org/20260515070312.130435-1-liuqiangneo@163.com
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 lib/test_hmm.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/test_hmm.c b/lib/test_hmm.c
index 38996c4baa40..63bf77dee987 100644
--- a/lib/test_hmm.c
+++ b/lib/test_hmm.c
@@ -1679,8 +1679,14 @@ static vm_fault_t dmirror_devmem_fault(struct vm_fault *vmf)
 	if (order)
 		args.flags |= MIGRATE_VMA_SELECT_COMPOUND;
 
-	if (migrate_vma_setup(&args))
-		return VM_FAULT_SIGBUS;
+	/*
+	 * In practice migrate_vma_setup() should never fail unless the
+	 * test is wrong as it just tests some static VMA properties.
+	 */
+	if (migrate_vma_setup(&args)) {
+		ret = VM_FAULT_SIGBUS;
+		goto err;
+	}
 
 	ret = dmirror_devmem_fault_alloc_and_copy(&args, dmirror);
 	if (ret)