Move the definition of the code to be written from
__jump_label_transform() to a specialized function.

Signed-off-by: Daniel Bristot de Oliveira <bris...@redhat.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Borislav Petkov <b...@alien8.de>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: Masami Hiramatsu <mhira...@kernel.org>
Cc: "Steven Rostedt (VMware)" <rost...@goodmis.org>
Cc: Jiri Kosina <jkos...@suse.cz>
Cc: Josh Poimboeuf <jpoim...@redhat.com>
Cc: "Peter Zijlstra (Intel)" <pet...@infradead.org>
Cc: Chris von Recklinghausen <creck...@redhat.com>
Cc: Jason Baron <jba...@akamai.com>
Cc: Scott Wood <sw...@redhat.com>
Cc: Marcelo Tosatti <mtosa...@redhat.com>
Cc: Clark Williams <willi...@redhat.com>
Cc: x...@kernel.org
Cc: linux-kernel@vger.kernel.org
---
 arch/x86/kernel/jump_label.c | 47 ++++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index f99bd26bd3f1..8aa65fbbd764 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -35,24 +35,20 @@ static void bug_at(unsigned char *ip, int line)
        BUG();
 }
 
-static void __ref __jump_label_transform(struct jump_entry *entry,
-                                        enum jump_label_type type,
-                                        void *(*poker)(void *, const void *, 
size_t),
-                                        int init)
+static void __jump_label_set_jump_code(struct jump_entry *entry,
+                                      enum jump_label_type type,
+                                      union jump_code_union *code,
+                                      int init)
 {
-       union jump_code_union jmp;
        const unsigned char default_nop[] = { STATIC_KEY_INIT_NOP };
        const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
-       const void *expect, *code;
+       const void *expect;
        int line;
 
-       jmp.jump = 0xe9;
-       jmp.offset = jump_entry_target(entry) -
+       code->jump = 0xe9;
+       code->offset = jump_entry_target(entry) -
                     (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
 
-       if (early_boot_irqs_disabled)
-               poker = text_poke_early;
-
        if (type == JUMP_LABEL_JMP) {
                if (init) {
                        expect = default_nop; line = __LINE__;
@@ -60,19 +56,34 @@ static void __ref __jump_label_transform(struct jump_entry 
*entry,
                        expect = ideal_nop; line = __LINE__;
                }
 
-               code = &jmp.code;
+               if (memcmp((void *)jump_entry_code(entry), expect, 
JUMP_LABEL_NOP_SIZE))
+                       bug_at((void *)jump_entry_code(entry), line);
+
        } else {
                if (init) {
                        expect = default_nop; line = __LINE__;
                } else {
-                       expect = &jmp.code; line = __LINE__;
+                       expect = code->code; line = __LINE__;
                }
 
-               code = ideal_nop;
+               if (memcmp((void *)jump_entry_code(entry), expect, 
JUMP_LABEL_NOP_SIZE))
+                       bug_at((void *)jump_entry_code(entry), line);
+
+               memcpy(code, ideal_nop, JUMP_LABEL_NOP_SIZE);
        }
+}
+
+static void __ref __jump_label_transform(struct jump_entry *entry,
+                                        enum jump_label_type type,
+                                        void *(*poker)(void *, const void *, 
size_t),
+                                        int init)
+{
+       union jump_code_union code;
+
+       if (early_boot_irqs_disabled)
+               poker = text_poke_early;
 
-       if (memcmp((void *)jump_entry_code(entry), expect, JUMP_LABEL_NOP_SIZE))
-               bug_at((void *)jump_entry_code(entry), line);
+       __jump_label_set_jump_code(entry, type, &code, init);
 
        /*
         * Make text_poke_bp() a default fallback poker.
@@ -83,12 +94,12 @@ static void __ref __jump_label_transform(struct jump_entry 
*entry,
         *
         */
        if (poker) {
-               (*poker)((void *)jump_entry_code(entry), code,
+               (*poker)((void *)jump_entry_code(entry), &code,
                         JUMP_LABEL_NOP_SIZE);
                return;
        }
 
-       text_poke_bp((void *)jump_entry_code(entry), code, JUMP_LABEL_NOP_SIZE,
+       text_poke_bp((void *)jump_entry_code(entry), &code, JUMP_LABEL_NOP_SIZE,
                     (void *)jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
 }
 
-- 
2.20.1

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