From b71b6e5f46fdc3f1b709b58777cb0da7ec9fc008 Mon Sep 17 00:00:00 2001
From: Zhipeng Xie <xiezhipeng1@huawei.com>
Date: Sun, 14 Nov 2021 17:26:59 +0800
Subject: [PATCH 03/24] create-diff-object:support
 kpatch_line_macro_change_only on aarch64

implement kpatch_line_macro_change_only on aarch64

Signed-off-by: Zhipeng Xie <xiezhipeng1@huawei.com>
---
 kpatch-build/create-diff-object.c | 63 +++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/kpatch-build/create-diff-object.c b/kpatch-build/create-diff-object.c
index 6c28280..c20f75e 100644
--- a/kpatch-build/create-diff-object.c
+++ b/kpatch-build/create-diff-object.c
@@ -757,6 +757,69 @@ static bool kpatch_line_macro_change_only(struct section *sec)
 
 	return true;
 }
+#elif __aarch64__
+#define ARM64_INSTR_LEN 4
+
+static bool kpatch_line_macro_change_only(struct section *sec)
+{
+	unsigned long start1, start2, size, offset;
+	struct rela *rela;
+	int lineonly = 0, found;
+	unsigned int mov_imm_mask = ((1<<16) - 1)<<5;
+
+	if (sec->status != CHANGED ||
+	    is_rela_section(sec) ||
+	    !is_text_section(sec) ||
+	    sec->sh.sh_size != sec->twin->sh.sh_size ||
+	    !sec->rela ||
+	    sec->rela->status != SAME)
+		return 0;
+
+	start1 = (unsigned long)sec->twin->data->d_buf;
+	start2 = (unsigned long)sec->data->d_buf;
+	size = sec->sh.sh_size;
+	for (offset = 0; offset < size; offset += ARM64_INSTR_LEN) {
+		if (!memcmp((void *)start1 + offset, (void *)start2 + offset,
+			    ARM64_INSTR_LEN))
+			continue;
+
+		/* verify it's a mov immediate to w1 */
+		if ((*(int *)(start1 + offset) & ~mov_imm_mask) !=
+				(*(int *)(start2 + offset) & ~mov_imm_mask))
+			return 0;
+
+		found = 0;
+		list_for_each_entry(rela, &sec->rela->relas, list) {
+			if (rela->offset < offset + ARM64_INSTR_LEN)
+				continue;
+			if (rela->string)
+				continue;
+			if (!strncmp(rela->sym->name, "__warned.", 9))
+				continue;
+			if (!strncmp(rela->sym->name, "warn_slowpath_", 14) ||
+			   (!strcmp(rela->sym->name, "__warn_printk")) ||
+			   (!strcmp(rela->sym->name, "__might_sleep")) ||
+			   (!strcmp(rela->sym->name, "___might_sleep")) ||
+			   (!strcmp(rela->sym->name, "__might_fault")) ||
+			   (!strcmp(rela->sym->name, "printk")) ||
+			   (!strcmp(rela->sym->name, "lockdep_rcu_suspicious"))) {
+				found = 1;
+				break;
+			}
+			return 0;
+		}
+		if (!found)
+			return 0;
+
+		lineonly = 1;
+	}
+
+	if (!lineonly)
+		ERROR("no instruction changes detected for changed section %s",
+		      sec->name);
+
+	return 1;
+}
 #else
 static bool kpatch_line_macro_change_only(struct section *sec)
 {
-- 
2.23.0