arm64: Add vmap_stack header file

Today the arm64 arch code allocates an extra IRQ stack per-cpu. If we
also have SDEI and VMAP stacks we need two extra per-cpu VMAP stacks.

Move the VMAP stack allocation out to a helper in a new header file.
This avoids missing THREADINFO_GFP, or getting the all-important alignment
wrong.

Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 2 insertions, 11 deletions

diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
index 713561e5bcab..60e5fc661f74 100644
--- a/arch/arm64/kernel/irq.c
+++ b/arch/arm64/kernel/irq.c
@@ -29,6 +29,7 @@
 #include <linux/irqchip.h>
 #include <linux/seq_file.h>
 #include <linux/vmalloc.h>
+#include <asm/vmap_stack.h>
 
 unsigned long irq_err_count;
 
@@ -58,17 +59,7 @@ static void init_irq_stacks(void)
 	unsigned long *p;
 
 	for_each_possible_cpu(cpu) {
-		/*
-		* To ensure that VMAP'd stack overflow detection works
-		* correctly, the IRQ stacks need to have the same
-		* alignment as other stacks.
-		*/
-		p = __vmalloc_node_range(IRQ_STACK_SIZE, THREAD_ALIGN,
-					 VMALLOC_START, VMALLOC_END,
-					 THREADINFO_GFP, PAGE_KERNEL,
-					 0, cpu_to_node(cpu),
-					 __builtin_return_address(0));
-
+		p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, cpu_to_node(cpu));
 		per_cpu(irq_stack_ptr, cpu) = p;
 	}
 }