From 8723942f7b4501c87a95b7446786e6f4ba3779cf Mon Sep 17 00:00:00 2001 From: Jon Medhurst Date: Thu, 9 Jun 2011 17:39:42 +0100 Subject: [PATCH] ARM: kprobes: Add emulate_ldrdstrd() This is an emulation function for the LDRD and STRD instructions. Signed-off-by: Jon Medhurst Acked-by: Nicolas Pitre --- arch/arm/kernel/kprobes-arm.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/arch/arm/kernel/kprobes-arm.c b/arch/arm/kernel/kprobes-arm.c index 8e4b7185f9fb..2b43d056fff5 100644 --- a/arch/arm/kernel/kprobes-arm.c +++ b/arch/arm/kernel/kprobes-arm.c @@ -893,6 +893,35 @@ prep_emulate_rdhi16rdlo12rs8rm0_wflags(kprobe_opcode_t insn, return INSN_GOOD; } +static void __kprobes +emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + unsigned long pc = (unsigned long)p->addr + 8; + int rt = (insn >> 12) & 0xf; + int rn = (insn >> 16) & 0xf; + int rm = insn & 0xf; + + register unsigned long rtv asm("r0") = regs->uregs[rt]; + register unsigned long rt2v asm("r1") = regs->uregs[rt+1]; + register unsigned long rnv asm("r2") = (rn == 15) ? pc + : regs->uregs[rn]; + register unsigned long rmv asm("r3") = regs->uregs[rm]; + + __asm__ __volatile__ ( + BLX("%[fn]") + : "=r" (rtv), "=r" (rt2v), "=r" (rnv) + : "0" (rtv), "1" (rt2v), "2" (rnv), "r" (rmv), + [fn] "r" (p->ainsn.insn_fn) + : "lr", "memory", "cc" + ); + + regs->uregs[rt] = rtv; + regs->uregs[rt+1] = rt2v; + if (is_writeback(insn)) + regs->uregs[rn] = rnv; +} + static void __kprobes emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs) { -- GitLab