[PATCH v2 10/24] mips/cpu: Make sure play_dead() doesn't return

Josh Poimboeuf
2023-02-14T07:08:39Z

play_dead() doesn't return. Make that more explicit with a BUG().

BUG() is preferable to unreachable() because BUG() is a more explicit
failure mode and avoids undefined behavior like falling off the edge of
the function into whatever code happens to be next.

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
arch/mips/kernel/smp-bmips.c | 2 ++
arch/mips/loongson64/smp.c | 1 +
2 files changed, 3 insertions(+)

diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
index df9158e8329d..be85fa075830 100644
--- a/arch/mips/kernel/smp-bmips.c
+++ b/arch/mips/kernel/smp-bmips.c
@@ -414,6 +414,8 @@ void __ref play_dead(void)
" wait\n"
" j bmips_secondary_reentry\n"
: : : "memory");
+
+ BUG();
}

#endif /* CONFIG_HOTPLUG_CPU */
diff --git a/arch/mips/loongson64/smp.c b/arch/mips/loongson64/smp.c
index 660e1de4412a..c81c2bd07c62 100644
--- a/arch/mips/loongson64/smp.c
+++ b/arch/mips/loongson64/smp.c
@@ -822,6 +822,7 @@ void play_dead(void)
state_addr = &per_cpu(cpu_state, cpu);
mb();
play_dead_at_ckseg1(state_addr);
+ BUG();
}

static int loongson3_disable_clock(unsigned int cpu)
--
2.39.1