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| author | Jon Medhurst <tixy@yxit.co.uk> | 2011-07-03 14:55:47 +0200 |
|---|---|---|
| committer | Tixy <tixy@medhuaa1.miniserver.com> | 2011-07-13 19:32:45 +0200 |
| commit | f39ca8b488a6c1e8db47746e1cdb841a6999edd7 (patch) | |
| tree | b04e1f1010e46a15d03e3ac93c685566c5eccbc1 /arch/arm/kernel/kprobes-thumb.c | |
| parent | ARM: kprobes: Reject 16-bit Thumb SETEND, CPS and BKPT instructions (diff) | |
| download | linux-f39ca8b488a6c1e8db47746e1cdb841a6999edd7.tar.xz linux-f39ca8b488a6c1e8db47746e1cdb841a6999edd7.zip | |
ARM: kprobes: Decode 32-bit Thumb hint instructions
For hints which may have observable effects, like SEV (send event), we
use kprobe_emulate_none which emulates the hint by executing the
original instruction.
For NOP we simulate the instruction using kprobe_simulate_nop, which
does nothing. As probes execute with interrupts disabled this is also
used for hints which may block for an indefinite time, like WFE (wait
for event).
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Diffstat (limited to 'arch/arm/kernel/kprobes-thumb.c')
| -rw-r--r-- | arch/arm/kernel/kprobes-thumb.c | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/arch/arm/kernel/kprobes-thumb.c b/arch/arm/kernel/kprobes-thumb.c index 554578bc5f09..27f83a32a038 100644 --- a/arch/arm/kernel/kprobes-thumb.c +++ b/arch/arm/kernel/kprobes-thumb.c @@ -37,6 +37,32 @@ static inline unsigned long __kprobes thumb_probe_pc(struct kprobe *p) return (unsigned long)p->addr - 1 + 4; } +static const union decode_item t32_table_1111_0xxx___1[] = { + /* Branches and miscellaneous control */ + + /* YIELD 1111 0011 1010 xxxx 10x0 x000 0000 0001 */ + DECODE_OR (0xfff0d7ff, 0xf3a08001), + /* SEV 1111 0011 1010 xxxx 10x0 x000 0000 0100 */ + DECODE_EMULATE (0xfff0d7ff, 0xf3a08004, kprobe_emulate_none), + /* NOP 1111 0011 1010 xxxx 10x0 x000 0000 0000 */ + /* WFE 1111 0011 1010 xxxx 10x0 x000 0000 0010 */ + /* WFI 1111 0011 1010 xxxx 10x0 x000 0000 0011 */ + DECODE_SIMULATE (0xfff0d7fc, 0xf3a08000, kprobe_simulate_nop), + + DECODE_END +}; + +const union decode_item kprobe_decode_thumb32_table[] = { + + /* + * Branches and miscellaneous control + * 1111 0xxx xxxx xxxx 1xxx xxxx xxxx xxxx + */ + DECODE_TABLE (0xf8008000, 0xf0008000, t32_table_1111_0xxx___1), + + DECODE_END +}; + static void __kprobes t16_simulate_bxblx(struct kprobe *p, struct pt_regs *regs) { @@ -551,5 +577,5 @@ thumb32_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) { asi->insn_singlestep = thumb32_singlestep; asi->insn_check_cc = thumb_check_cc; - return INSN_REJECTED; + return kprobe_decode_insn(insn, asi, kprobe_decode_thumb32_table, true); } |