Subject: [PATCH v6 02/11] selftest/mremap_test: Avoid crash with static build

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Mon, 24 May 2021 14:31:05 +0530

With a large mmap map size, we can overlap with the text area and using
MAP_FIXED results in unmapping that area. Switch to MAP_FIXED_NOREPLACE
and handle the EEXIST error.

Reviewed-by: Kalesh Singh <[email-masked]>
Signed-off-by: Aneesh Kumar K.V <[email-masked]>
---
 tools/testing/selftests/vm/mremap_test.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/vm/mremap_test.c b/tools/testing/selftests/vm/mremap_test.c
index c9a5461eb786..0624d1bd71b5 100644
--- a/tools/testing/selftests/vm/mremap_test.c
+++ b/tools/testing/selftests/vm/mremap_test.c
@@ -75,9 +75,10 @@ static void *get_source_mapping(struct config c)
 retry:
 	addr += c.src_alignment;
 	src_addr = mmap((void *) addr, c.region_size, PROT_READ | PROT_WRITE,
-			MAP_FIXED | MAP_ANONYMOUS | MAP_SHARED, -1, 0);
+			MAP_FIXED_NOREPLACE | MAP_ANONYMOUS | MAP_SHARED,
+			-1, 0);
 	if (src_addr == MAP_FAILED) {
-		if (errno == EPERM)
+		if (errno == EPERM || errno == EEXIST)
 			goto retry;
 		goto error;
 	}
-- 
2.31.1