[PATCH] kvm: arm64: use BUG() instead of BUG_ON(1)

Arnd Bergmann
2025-08-07T07:24:26Z

From: Arnd Bergmann <arnd@arndb.de>

The BUG_ON() macro adds a little bit of complexity over BUG(), and in
some cases this ends up confusing the compiler's control flow analysis
in a way that results in a warning. This one now shows up with clang-21:

arch/arm64/kvm/vgic/vgic-mmio.c:1094:3: error: variable 'len' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
1094 | BUG_ON(1);

Change both instances of BUG_ON(1) to a plain BUG() in the arm64 kvm
code, to avoid the false-positive warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
arch/arm64/kvm/hyp/nvhe/list_debug.c | 2 +-
arch/arm64/kvm/vgic/vgic-mmio.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/hyp/nvhe/list_debug.c b/arch/arm64/kvm/hyp/nvhe/list_debug.c
index 46a2d4f2b3c6..baa6260f88dc 100644
--- a/arch/arm64/kvm/hyp/nvhe/list_debug.c
+++ b/arch/arm64/kvm/hyp/nvhe/list_debug.c
@@ -17,7 +17,7 @@ static inline __must_check bool nvhe_check_data_corruption(bool v)
bool corruption = unlikely(condition); \
if (corruption) { \
if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
- BUG_ON(1); \
+ BUG(); \
} else \
WARN_ON(1); \
} \
diff --git a/arch/arm64/kvm/vgic/vgic-mmio.c b/arch/arm64/kvm/vgic/vgic-mmio.c
index e416e433baff..a573b1f0c6cb 100644
--- a/arch/arm64/kvm/vgic/vgic-mmio.c
+++ b/arch/arm64/kvm/vgic/vgic-mmio.c
@@ -1091,7 +1091,7 @@ int vgic_register_dist_iodev(struct kvm *kvm, gpa_t dist_base_address,
len = vgic_v3_init_dist_iodev(io_device);
break;
default:
- BUG_ON(1);
+ BUG();
}

io_device->base_addr = dist_base_address;
--
2.39.5