arm64: move on_thread_stack() to <asm/stacktrace.h>

Currently on_thread_stack() is defined in <asm/processor.h>, depending
upon definitiong from <asm/stacktrace.h> despite this header not being
included. This ends up being fragile, and any user of on_thread_stack()
must include both <asm/processor.h> and <asm/stacktrace.h>.

We organised things this way due to header dependencies back in commit:

  0b3e336 ("arm64: Add support for STACKLEAK gcc plugin")

... but now that we no longer use current_top_of_stack(), and given that
stackleak includes <asm/stacktrace.h> via <linux/stackleak.h>, we no
longer need the definition to live in <asm/processor.h>.

Move on_thread_stack() to <asm/stacktrace.h>, where all its dependencies
are guaranteed to be defined. This requires having arm64's irq.c
explicitly include <asm/stacktrace.h>, and I've taken the opportunity to
sort the includes, which were slightly out of order.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20221117120902.3974163-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

Author: mrutland-arm

arch/arm64/include/asm/processor.h

@@ -396,7 +396,5 @@ long get_tagged_addr_ctrl(struct task_struct *task);
 #define GET_TAGGED_ADDR_CTRL()		get_tagged_addr_ctrl(current)
 #endif
 
-#define on_thread_stack()	(on_task_stack(current, current_stack_pointer, 1))
-
 #endif /* __ASSEMBLY__ */
 #endif /* __ASM_PROCESSOR_H */

arch/arm64/include/asm/stacktrace.h

@@ -57,6 +57,8 @@ static inline bool on_task_stack(const struct task_struct *tsk,
 	return stackinfo_on_stack(&info, sp, size);
 }
 
+#define on_thread_stack()	(on_task_stack(current, current_stack_pointer, 1))
+
 #ifdef CONFIG_VMAP_STACK
 DECLARE_PER_CPU(unsigned long [OVERFLOW_STACK_SIZE/sizeof(long)], overflow_stack);
 

arch/arm64/kernel/irq.c

@@ -10,20 +10,21 @@
  * Copyright (C) 2012 ARM Ltd.
  */
 
-#include <linux/irq.h>
-#include <linux/memory.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/vmap_stack.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);