[PATCH v11 8/9] arm64: Add kernel return probes support (kretprobes)
From: 平松雅巳 / HIRAMATU，MASAMI <hidden>
Date: 2016-03-17 12:22:38
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lkml
Hi,
From: Sandeepa Prabhu <redacted> 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.
quoted hunk ↗ jump to hunk
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?? Thank you,
int __init arch_init_kprobes(void) -- 2.5.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel at lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel