diff options
Diffstat (limited to 'arch/s390/include/asm/jump_label.h')
-rw-r--r-- | arch/s390/include/asm/jump_label.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h index 346b1c85ffb4..58642fd29c87 100644 --- a/arch/s390/include/asm/jump_label.h +++ b/arch/s390/include/asm/jump_label.h @@ -4,6 +4,7 @@ #include <linux/types.h> #define JUMP_LABEL_NOP_SIZE 6 +#define JUMP_LABEL_NOP_OFFSET 2 #ifdef CONFIG_64BIT #define ASM_PTR ".quad" @@ -13,9 +14,13 @@ #define ASM_ALIGN ".balign 4" #endif +/* + * We use a brcl 0,2 instruction for jump labels at compile time so it + * can be easily distinguished from a hotpatch generated instruction. + */ static __always_inline bool arch_static_branch(struct static_key *key) { - asm_volatile_goto("0: brcl 0,0\n" + asm_volatile_goto("0: brcl 0,"__stringify(JUMP_LABEL_NOP_OFFSET)"\n" ".pushsection __jump_table, \"aw\"\n" ASM_ALIGN "\n" ASM_PTR " 0b, %l[label], %0\n" |