>From: 平松雅巳 / HIRAMATU，MASAMI [mailto:masami.hiramatsu...@hitachi.com] > >Hi, > >>From: Sandeepa Prabhu <sandeepa.s.pra...@gmail.com> >> >>The pre-handler of this special 'trampoline' kprobe executes the return >>probe handler functions and restores original return address in ELR_EL1. >>This way the saved pt_regs still hold the original register context to be >>carried back to the probed kernel function. > >This patch seems not well separated. > >>diff --git a/arch/arm64/kernel/kprobes.c b/arch/arm64/kernel/kprobes.c >>index bd3f233..13d3333 100644 >>--- a/arch/arm64/kernel/kprobes.c >>+++ b/arch/arm64/kernel/kprobes.c > >[snip] > >>+void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, >>+ struct pt_regs *regs) >>+{ >>+ ri->ret_addr = (kprobe_opcode_t *)regs->regs[30]; >>+ >>+ /* replace return addr (x30) with trampoline */ >>+ regs->regs[30] = (long)&kretprobe_trampoline; > >So, where is the kretprobe_trampoline? It seems that function is >defined in other patch. > >>+} >>+ >>+int __kprobes arch_trampoline_kprobe(struct kprobe *p) >>+{ >>+ return 0; >> } > >And what this function is for??
Ah, sorry, this was my fault. Yes, this function is required. But this implementation also means there is an asm-based trampoline function which should be included in this patch. David, could you tell me the repository which I can get the latest version of this series? I'd like to see the whole code of kprobes/arm64. Thank you,
