diff options
Diffstat (limited to 'arch/mips/kernel')
| -rw-r--r-- | arch/mips/kernel/kprobes.c | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/mips/kernel/kprobes.c b/arch/mips/kernel/kprobes.c index 9fb1876cb0b..0ab1a5ff104 100644 --- a/arch/mips/kernel/kprobes.c +++ b/arch/mips/kernel/kprobes.c @@ -113,6 +113,30 @@ insn_ok: return 0; } +/* + * insn_has_ll_or_sc function checks whether instruction is ll or sc + * one; putting breakpoint on top of atomic ll/sc pair is bad idea; + * so we need to prevent it and refuse kprobes insertion for such + * instructions; cannot do much about breakpoint in the middle of + * ll/sc pair; it is upto user to avoid those places + */ +static int __kprobes insn_has_ll_or_sc(union mips_instruction insn) +{ + int ret = 0; + + switch (insn.i_format.opcode) { + case ll_op: + case lld_op: + case sc_op: + case scd_op: + ret = 1; + break; + default: + break; + } + return ret; +} + int __kprobes arch_prepare_kprobe(struct kprobe *p) { union mips_instruction insn; @@ -121,6 +145,13 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) insn = p->addr[0]; + if (insn_has_ll_or_sc(insn)) { + pr_notice("Kprobes for ll and sc instructions are not" + "supported\n"); + ret = -EINVAL; + goto out; + } + if (insn_has_delayslot(insn)) { pr_notice("Kprobes for branch and jump instructions are not" "supported\n"); |