summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/kprobes-thumb.c
diff options
context:
space:
mode:
authorJon Medhurst <tixy@yxit.co.uk>2011-07-03 13:55:47 +0100
committerTixy <tixy@medhuaa1.miniserver.com>2011-07-13 17:32:45 +0000
commitf39ca8b488a6c1e8db47746e1cdb841a6999edd7 (patch)
treeb04e1f1010e46a15d03e3ac93c685566c5eccbc1 /arch/arm/kernel/kprobes-thumb.c
parent0a188ccb5eceb58101fcc11b3ec2d860ccbf92a3 (diff)
downloadop-kernel-dev-f39ca8b488a6c1e8db47746e1cdb841a6999edd7.zip
op-kernel-dev-f39ca8b488a6c1e8db47746e1cdb841a6999edd7.tar.gz
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.c28
1 files changed, 27 insertions, 1 deletions
diff --git a/arch/arm/kernel/kprobes-thumb.c b/arch/arm/kernel/kprobes-thumb.c
index 554578b..27f83a3 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);
}
OpenPOWER on IntegriCloud