Messages in this thread Patch in this message | | | From | Wang Nan <> | Subject | [RFC PATCH 03/11] x86: kprobes: directly modify code if kprobe is not initialized. | Date | Wed, 7 Jan 2015 15:35:33 +0800 |
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When registering early kprobes, SMP should has not been enabled, so doesn't require synchronization in text_poke_bp(). Simply memcpy is enough.
Signed-off-by: Wang Nan <wangnan0@huawei.com> --- arch/x86/kernel/kprobes/opt.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index 0dd8d08..dc5fccb 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -397,8 +397,11 @@ void arch_optimize_kprobes(struct list_head *oplist) insn_buf[0] = RELATIVEJUMP_OPCODE; *(s32 *)(&insn_buf[1]) = rel; - text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE, - op->optinsn.insn); + if (unlikely(!kprobes_initialized)) + memcpy(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE); + else + text_poke_bp(op->kp.addr, insn_buf, RELATIVEJUMP_SIZE, + op->optinsn.insn); list_del_init(&op->list); } -- 1.8.4
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