linux-kernel - [PATCH] KVM: selftests: do not require 64GB in set_memory_region

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210701160425.33666-1-borntraeger@de.ibm.com>
Date:   Thu,  1 Jul 2021 18:04:25 +0200
From:   Christian Borntraeger <borntraeger@...ibm.com>
To:     Shuah Khan <shuah@...nel.org>
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Zenghui Yu <yuzenghui@...wei.com>, kvm@...r.kernel.org,
        linux-kselftest@...r.kernel.org, linux-kernel@...r.kernel.org,
        linux-s390@...r.kernel.org,
        Christian Borntraeger <borntraeger@...ibm.com>,
        vkuznets@...hat.com, wanghaibin.wang@...wei.com
Subject: [PATCH] KVM: selftests: do not require 64GB in set_memory_region_test

Unless the user sets overcommit_memory or has plenty of swap, the latest
changes to the testcase will result in ENOMEM failures for hosts with
less than 64GB RAM. As we do not use much of the allocated memory, we
can use MAP_NORESERVE to avoid this error.

Cc: Zenghui Yu <yuzenghui@...wei.com>
Cc: vkuznets@...hat.com
Cc: wanghaibin.wang@...wei.com
Cc: stable@...r.kernel.org
Fixes: 309505dd5685 ("KVM: selftests: Fix mapping length truncation in m{,un}map()")
Signed-off-by: Christian Borntraeger <borntraeger@...ibm.com>
---
 tools/testing/selftests/kvm/set_memory_region_test.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index d8812f27648c..d31f54ac4e98 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -377,7 +377,8 @@ static void test_add_max_memory_regions(void)
 		(max_mem_slots - 1), MEM_REGION_SIZE >> 10);
 
 	mem = mmap(NULL, (size_t)max_mem_slots * MEM_REGION_SIZE + alignment,
-		   PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+		   PROT_READ | PROT_WRITE,
+		   MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE, -1, 0);
 	TEST_ASSERT(mem != MAP_FAILED, "Failed to mmap() host");
 	mem_aligned = (void *)(((size_t) mem + alignment - 1) & ~(alignment - 1));
 
-- 
2.31.1