ARM: 6412/1: kprobes-decode: add support for MOVW instruction

The MOVW instruction moves a 16-bit immediate into the bottom halfword
of the destination register.

This patch ensures that kprobes leaves the 16-bit immediate intact, rather
than assume a 12-bit immediate and mask out the upper 4 bits.

Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Will Deacon 2010-09-27 18:12:12 +01:00 committed by Russell King
parent 7f58217bb6
commit ccdf2e1bca

View file

@ -1162,11 +1162,12 @@ space_cccc_001x(kprobe_opcode_t insn, struct arch_specific_insn *asi)
{
/*
* MSR : cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx
* Undef : cccc 0011 0x00 xxxx xxxx xxxx xxxx xxxx
* Undef : cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx
* ALU op with S bit and Rd == 15 :
* cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx
*/
if ((insn & 0x0f900000) == 0x03200000 || /* MSR & Undef */
if ((insn & 0x0fb00000) == 0x03200000 || /* MSR */
(insn & 0x0ff00000) == 0x03400000 || /* Undef */
(insn & 0x0e10f000) == 0x0210f000) /* ALU s-bit, R15 */
return INSN_REJECTED;
@ -1177,7 +1178,7 @@ space_cccc_001x(kprobe_opcode_t insn, struct arch_specific_insn *asi)
* *S (bit 20) updates condition codes
* ADC/SBC/RSC reads the C flag
*/
insn &= 0xfff00fff; /* Rn = r0, Rd = r0 */
insn &= 0xffff0fff; /* Rd = r0 */
asi->insn[0] = insn;
asi->insn_handler = (insn & (1 << 20)) ? /* S-bit */
emulate_alu_imm_rwflags : emulate_alu_imm_rflags;