1 files changed, 94 insertions, 28 deletions

diff --git a/arch/arm64/kernel/irq.c b/arch/arm64/kernel/irq.c
index 2386b26c0712..15dedb385b9e 100644
--- a/arch/arm64/kernel/irq.c
+++ b/arch/arm64/kernel/irq.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * Based on arch/arm/kernel/irq.c
  *
@@ -7,52 +8,117 @@
  * Dynamic Tick Timer written by Tony Lindgren <tony@atomide.com> and
  * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>.
  * Copyright (C) 2012 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <linux/kernel_stat.h>
-#include <linux/irq.h>
-#include <linux/smp.h>
+#include <linux/hardirq.h>
 #include <linux/init.h>
+#include <linux/irq.h>
 #include <linux/irqchip.h>
+#include <linux/kprobes.h>
+#include <linux/memory.h>
+#include <linux/scs.h>
 #include <linux/seq_file.h>
+#include <linux/smp.h>
+#include <linux/vmalloc.h>
+#include <asm/daifflags.h>
+#include <asm/exception.h>
+#include <asm/numa.h>
+#include <asm/softirq_stack.h>
+#include <asm/stacktrace.h>
+#include <asm/vmap_stack.h>
+
+/* Only access this in an NMI enter/exit */
+DEFINE_PER_CPU(struct nmi_ctx, nmi_contexts);
+
+DEFINE_PER_CPU(unsigned long *, irq_stack_ptr);
+
 
-unsigned long irq_err_count;
+DECLARE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr);
 
-/* irq stack only needs to be 16 byte aligned - not IRQ_STACK_SIZE aligned. */
-DEFINE_PER_CPU(unsigned long [IRQ_STACK_SIZE/sizeof(long)], irq_stack) __aligned(16);
+#ifdef CONFIG_SHADOW_CALL_STACK
+DEFINE_PER_CPU(unsigned long *, irq_shadow_call_stack_ptr);
+#endif
 
-int arch_show_interrupts(struct seq_file *p, int prec)
+static void init_irq_scs(void)
 {
-	show_ipi_list(p, prec);
-	seq_printf(p, "%*s: %10lu\n", prec, "Err", irq_err_count);
-	return 0;
+	int cpu;
+
+	if (!scs_is_enabled())
+		return;
+
+	for_each_possible_cpu(cpu)
+		per_cpu(irq_shadow_call_stack_ptr, cpu) =
+			scs_alloc(early_cpu_to_node(cpu));
 }
 
-void (*handle_arch_irq)(struct pt_regs *) = NULL;
+static void __init init_irq_stacks(void)
+{
+	int cpu;
+	unsigned long *p;
 
-void __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
+	for_each_possible_cpu(cpu) {
+		p = arch_alloc_vmap_stack(IRQ_STACK_SIZE, early_cpu_to_node(cpu));
+		per_cpu(irq_stack_ptr, cpu) = p;
+	}
+}
+
+#ifdef CONFIG_SOFTIRQ_ON_OWN_STACK
+static void ____do_softirq(struct pt_regs *regs)
 {
-	if (handle_arch_irq)
-		return;
+	__do_softirq();
+}
+
+void do_softirq_own_stack(void)
+{
+	call_on_irq_stack(NULL, ____do_softirq);
+}
+#endif
+
+static void default_handle_irq(struct pt_regs *regs)
+{
+	panic("IRQ taken without a root IRQ handler\n");
+}
+
+static void default_handle_fiq(struct pt_regs *regs)
+{
+	panic("FIQ taken without a root FIQ handler\n");
+}
+
+void (*handle_arch_irq)(struct pt_regs *) __ro_after_init = default_handle_irq;
+void (*handle_arch_fiq)(struct pt_regs *) __ro_after_init = default_handle_fiq;
+
+int __init set_handle_irq(void (*handle_irq)(struct pt_regs *))
+{
+	if (handle_arch_irq != default_handle_irq)
+		return -EBUSY;
 
 	handle_arch_irq = handle_irq;
+	pr_info("Root IRQ handler: %ps\n", handle_irq);
+	return 0;
+}
+
+int __init set_handle_fiq(void (*handle_fiq)(struct pt_regs *))
+{
+	if (handle_arch_fiq != default_handle_fiq)
+		return -EBUSY;
+
+	handle_arch_fiq = handle_fiq;
+	pr_info("Root FIQ handler: %ps\n", handle_fiq);
+	return 0;
 }
 
 void __init init_IRQ(void)
 {
+	init_irq_stacks();
+	init_irq_scs();
 	irqchip_init();
-	if (!handle_arch_irq)
-		panic("No interrupt controller found.");
+
+	if (system_uses_irq_prio_masking()) {
+		/*
+		 * Now that we have a stack for our IRQ handler, set
+		 * the PMR/PSR pair to a consistent state.
+		 */
+		WARN_ON(read_sysreg(daif) & PSR_A_BIT);
+		local_daif_restore(DAIF_PROCCTX_NOIRQ);
+	}
 }