[RFC PATCH v3 17/22] arm64: Add kernel and module support for ORC

[madvenka@linux.microsoft.com]

From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com>

Call orc_lookup_init() from setup_arch() to perform ORC lookup
initialization for vmlinux.

Call orc_lookup_module_init() in module load to perform ORC lookup
initialization for modules.

Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
---
 arch/arm64/kernel/module.c | 13 ++++++++++++-
 arch/arm64/kernel/setup.c  |  2 ++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index 76b41e4ca9fa..71264a181f61 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -19,6 +19,7 @@
 #include <asm/alternative.h>
 #include <asm/insn.h>
 #include <asm/sections.h>
+#include <asm-generic/orc_lookup.h>
 
 void *module_alloc(unsigned long size)
 {
@@ -509,10 +510,20 @@ int module_finalize(const Elf_Ehdr *hdr,
 		    const Elf_Shdr *sechdrs,
 		    struct module *me)
 {
-	const Elf_Shdr *s;
+	const Elf_Shdr *s, *orc, *orc_ip;
+
 	s = find_section(hdr, sechdrs, ".altinstructions");
 	if (s)
 		apply_alternatives_module((void *)s->sh_addr, s->sh_size);
 
+	orc = find_section(hdr, sechdrs, ".orc_unwind");
+	orc_ip = find_section(hdr, sechdrs, ".orc_unwind_ip");
+
+	if (orc && orc_ip) {
+		orc_lookup_module_init(me,
+				       (void *)orc_ip->sh_addr, orc_ip->sh_size,
+				       (void *)orc->sh_addr, orc->sh_size);
+	}
+
 	return module_init_ftrace_plt(hdr, sechdrs, me);
 }
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index fea3223704b6..360304dcd8c2 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -51,6 +51,7 @@
 #include <asm/efi.h>
 #include <asm/xen/hypervisor.h>
 #include <asm/mmu_context.h>
+#include <asm-generic/orc_lookup.h>
 
 static int num_standard_resources;
 static struct resource *standard_resources;
@@ -378,6 +379,7 @@ void __init __no_sanitize_address setup_arch(char **cmdline_p)
 			"This indicates a broken bootloader or old kernel\n",
 			boot_args[1], boot_args[2], boot_args[3]);
 	}
+	orc_lookup_init();
 }
 
 static inline bool cpu_can_disable(unsigned int cpu)
-- 
2.25.1