linux-kernel - [PATCH] KVM: arm64: Don't return from void function

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Message-Id: <20220705142310.3847918-1-qperret@google.com>
Date:   Tue,  5 Jul 2022 14:23:10 +0000
From:   Quentin Perret <qperret@...gle.com>
To:     Marc Zyngier <maz@...nel.org>, James Morse <james.morse@....com>,
        Alexandru Elisei <alexandru.elisei@....com>,
        Suzuki K Poulose <suzuki.poulose@....com>,
        Oliver Upton <oliver.upton@...ux.dev>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>,
        linux-arm-kernel@...ts.infradead.org, kvmarm@...ts.cs.columbia.edu,
        linux-kernel@...r.kernel.org
Cc:     kernel-team@...roid.com, qperret@...gle.com
Subject: [PATCH] KVM: arm64: Don't return from void function

Although harmless, the return statement in kvm_unexpected_el2_exception
is rather confusing as the function itself has a void return type. The
C standard is also pretty clear that "A return statement with an
expression shall not appear in a function whose return type is void".
Given that this return statement does not seem to add any actual value,
let's not pointlessly violate the standard.

Build-tested with GCC 10 and CLANG 13 for good measure, the disassembled
code is identical with or without the return statement.

Fixes: e9ee186bb735 ("KVM: arm64: Add kvm_extable for vaxorcism code")
Signed-off-by: Quentin Perret <qperret@...gle.com>
---
 arch/arm64/kvm/hyp/nvhe/switch.c | 2 +-
 arch/arm64/kvm/hyp/vhe/switch.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c
index 6db801db8f27..925b34b7708d 100644
--- a/arch/arm64/kvm/hyp/nvhe/switch.c
+++ b/arch/arm64/kvm/hyp/nvhe/switch.c
@@ -386,5 +386,5 @@ asmlinkage void __noreturn hyp_panic_bad_stack(void)
 
 asmlinkage void kvm_unexpected_el2_exception(void)
 {
-	return __kvm_unexpected_el2_exception();
+	__kvm_unexpected_el2_exception();
 }
diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
index 969f20daf97a..390af1a6a9b4 100644
--- a/arch/arm64/kvm/hyp/vhe/switch.c
+++ b/arch/arm64/kvm/hyp/vhe/switch.c
@@ -249,5 +249,5 @@ void __noreturn hyp_panic(void)
 
 asmlinkage void kvm_unexpected_el2_exception(void)
 {
-	return __kvm_unexpected_el2_exception();
+	__kvm_unexpected_el2_exception();
 }
-- 
2.37.0.rc0.161.g10f37bed90-goog