Re: [PATCH MANUALSEL 5.15 2/7] KVM: selftests: Silence compiler warning in the kvm_page_table_test

From: Paolo Bonzini
Date: Wed Apr 27 2022 - 12:24:07 EST


On 4/27/22 17:54, Sasha Levin wrote:
From: Thomas Huth <thuth@xxxxxxxxxx>

[ Upstream commit 266a19a0bc4fbfab4d981a47640ca98972a01865 ]

When compiling kvm_page_table_test.c, I get this compiler warning
with gcc 11.2:

kvm_page_table_test.c: In function 'pre_init_before_test':
../../../../tools/include/linux/kernel.h:44:24: warning: comparison of
distinct pointer types lacks a cast
44 | (void) (&_max1 == &_max2); \
| ^~
kvm_page_table_test.c:281:21: note: in expansion of macro 'max'
281 | alignment = max(0x100000, alignment);
| ^~~

Fix it by adjusting the type of the absolute value.

Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx>
Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
Message-Id: <20220414103031.565037-1-thuth@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/testing/selftests/kvm/kvm_page_table_test.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/kvm_page_table_test.c b/tools/testing/selftests/kvm/kvm_page_table_test.c
index 36407cb0ec85..f1ddfe4c4a03 100644
--- a/tools/testing/selftests/kvm/kvm_page_table_test.c
+++ b/tools/testing/selftests/kvm/kvm_page_table_test.c
@@ -278,7 +278,7 @@ static struct kvm_vm *pre_init_before_test(enum vm_guest_mode mode, void *arg)
else
guest_test_phys_mem = p->phys_offset;
#ifdef __s390x__
- alignment = max(0x100000, alignment);
+ alignment = max(0x100000UL, alignment);
#endif
guest_test_phys_mem &= ~(alignment - 1);

Acked-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>