[PATCH 4/8] arm64: remove CONFIG_VMAP_STACK conditionals from irq stack setup

From: Breno Leitao
Date: Mon Jul 07 2025 - 12:02:05 EST


With VMAP_STACK always enabled on arm64, drop the CONFIG_VMAP_STACK
checks and legacy irq stack allocation from arch/arm64/kernel/irq.c. The
code now unconditionally uses the VMAP_STACK path for irq stack
initialization, simplifying the logic.

Signed-off-by: Breno Leitao <leitao@xxxxxxxxxx>
---
arch/arm64/kernel/irq.c | 13 -------------
1 file changed, 13 deletions(-)

diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
index 85087e2df564..c0065a1d77cf 100644
--- a/arch/arm64/kernel/irq.c
+++ b/arch/arm64/kernel/irq.c
@@ -51,7 +51,6 @@ static void init_irq_scs(void)
scs_alloc(early_cpu_to_node(cpu));
}

-#ifdef CONFIG_VMAP_STACK
static void __init init_irq_stacks(void)
{
int cpu;
@@ -62,18 +61,6 @@ static void __init init_irq_stacks(void)
per_cpu(irq_stack_ptr, cpu) = p;
}
}
-#else
-/* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
-DEFINE_PER_CPU_ALIGNED(unsigned long [IRQ_STACK_SIZE/sizeof(long)], irq_stack);
-
-static void init_irq_stacks(void)
-{
- int cpu;
-
- for_each_possible_cpu(cpu)
- per_cpu(irq_stack_ptr, cpu) = per_cpu(irq_stack, cpu);
-}
-#endif

#ifndef CONFIG_PREEMPT_RT
static void ____do_softirq(struct pt_regs *regs)

--
2.47.1