From d59bee887231191c80f2ee674d7ec19179eb40ec Mon Sep 17 00:00:00 2001 From: "David A. Long" Date: Fri, 8 Jul 2016 12:35:46 -0400 Subject: arm64: Add more test functions to insn.c Certain instructions are hard to execute correctly out-of-line (as in kprobes). Test functions are added to insn.[hc] to identify these. The instructions include any that use PC-relative addressing, change the PC, or change interrupt masking. For efficiency and simplicity test functions are also added for small collections of related instructions. Signed-off-by: David A. Long Acked-by: Masami Hiramatsu Signed-off-by: Catalin Marinas --- arch/arm64/kernel/insn.c | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) (limited to 'arch/arm64/kernel') diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c index 368c08290dd8..28c6110ffcbb 100644 --- a/arch/arm64/kernel/insn.c +++ b/arch/arm64/kernel/insn.c @@ -162,6 +162,32 @@ static bool __kprobes __aarch64_insn_hotpatch_safe(u32 insn) aarch64_insn_is_nop(insn); } +bool __kprobes aarch64_insn_uses_literal(u32 insn) +{ + /* ldr/ldrsw (literal), prfm */ + + return aarch64_insn_is_ldr_lit(insn) || + aarch64_insn_is_ldrsw_lit(insn) || + aarch64_insn_is_adr_adrp(insn) || + aarch64_insn_is_prfm_lit(insn); +} + +bool __kprobes aarch64_insn_is_branch(u32 insn) +{ + /* b, bl, cb*, tb*, b.cond, br, blr */ + + return aarch64_insn_is_b(insn) || + aarch64_insn_is_bl(insn) || + aarch64_insn_is_cbz(insn) || + aarch64_insn_is_cbnz(insn) || + aarch64_insn_is_tbz(insn) || + aarch64_insn_is_tbnz(insn) || + aarch64_insn_is_ret(insn) || + aarch64_insn_is_br(insn) || + aarch64_insn_is_blr(insn) || + aarch64_insn_is_bcond(insn); +} + /* * ARM Architecture Reference Manual for ARMv8 Profile-A, Issue A.a * Section B2.6.5 "Concurrent modification and execution of instructions": @@ -1175,6 +1201,14 @@ u32 aarch64_set_branch_offset(u32 insn, s32 offset) BUG(); } +/* + * Extract the Op/CR data from a msr/mrs instruction. + */ +u32 aarch64_insn_extract_system_reg(u32 insn) +{ + return (insn & 0x1FFFE0) >> 5; +} + bool aarch32_insn_is_wide(u32 insn) { return insn >= 0xe800; -- cgit v1.2.3