[PATCH] KVM: x86: Fix pointer mistmatch warning when patching RET0 static calls

From: Sean Christopherson
Date: Wed Feb 23 2022 - 11:24:04 EST


Cast kvm_x86_ops.func to 'void *' when updating KVM static calls that are
conditionally patched to __static_call_return0(). clang complains about
using mismatching pointers in the ternary operator, which breaks the
build when compiling with CONFIG_KVM_WERROR=y.

>> arch/x86/include/asm/kvm-x86-ops.h:82:1: warning: pointer type mismatch
('bool (*)(struct kvm_vcpu *)' and 'void *') [-Wpointer-type-mismatch]

Fixes: 5be2226f417d ("KVM: x86: allow defining return-0 static calls")
Reported-by: Like Xu <like.xu.linux@xxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 713e08f62385..f285ddb8b66b 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1547,8 +1547,8 @@ static inline void kvm_ops_static_call_update(void)
WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func)
#define KVM_X86_OP_OPTIONAL __KVM_X86_OP
#define KVM_X86_OP_OPTIONAL_RET0(func) \
- static_call_update(kvm_x86_##func, kvm_x86_ops.func ? : \
- (void *) __static_call_return0);
+ static_call_update(kvm_x86_##func, (void *)kvm_x86_ops.func ? : \
+ (void *)__static_call_return0);
#include <asm/kvm-x86-ops.h>
#undef __KVM_X86_OP
}

base-commit: f4bc051fc91ab9f1d5225d94e52d369ef58bec58
--
2.35.1.473.g83b2b277ed-goog