From e9482399d7eee7199a4a31fe943c940f52a245ba Mon Sep 17 00:00:00 2001
Message-Id: <e9482399d7eee7199a4a31fe943c940f52a245ba.1566225007.git.aquini@redhat.com>
In-Reply-To: <d42f467a923dfc09309acb7a83b42e3285fbd8f4.1566225007.git.aquini@redhat.com>
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From: Sandipan Das <sandipan@linux.ibm.com>
Date: Mon, 19 Aug 2019 14:48:38 +0530
Subject: [RHEL7 PATCH 31/31] tests: noresv-preserve-resv-page: Fix failure in
 case of overcommit

This adds an additional check to see if the mapping created
with MAP_NORESERVE does not raise a SIGBUS upon being written
to because nr_overcommit_pages is set to a non-zero value and
surplus pages gets provisioned. In this case, the test should
pass.

Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Eric B Munson <eric@munsonfam.org>
Signed-off-by: Rafael Aquini <aquini@redhat.com>
---
 tests/noresv-preserve-resv-page.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tests/noresv-preserve-resv-page.c b/tests/noresv-preserve-resv-page.c
index b7b8043..b93bf36 100644
--- a/tests/noresv-preserve-resv-page.c
+++ b/tests/noresv-preserve-resv-page.c
@@ -66,6 +66,7 @@ int main(int argc, char *argv[])
 {
 	long hpage_size;
 	int nr_hugepages;
+	int surp_hugepages;
 	int fd1, fd2, err;
 	char *p, *q;
 	struct sigaction sa = {
@@ -104,6 +105,13 @@ int main(int argc, char *argv[])
 
 	verbose_printf("Write to %p to steal reserved page\n", q);
 
+	surp_hugepages = get_huge_page_counter(hpage_size, HUGEPAGES_SURP);
 	test_write(q);
+
+	/* Provisioning succeeded because of overcommit */
+	if (get_huge_page_counter(hpage_size, HUGEPAGES_SURP) ==
+	    surp_hugepages + 1)
+		PASS();
+
 	FAIL("Steal reserved page");
 }
-- 
1.8.3.1