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POGetting args from kprobe not finding regs->rdi x86_64
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14221590
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2013-01-08T18:24:48.050
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2013-01-08T18:57:16.243
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2017-05-23T11:56:44.437
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I'm writing a kernel module under Scientific Linux 6.3 x86_64 and I'm looking to use kprobes. In this module, I need access to the first argument of a function on return, so jprobes are out. I found this very helpful post: <a href="https://stackoverflow.com/questions/10563635/getting-function-arguments-using-kprobes">Getting function arguments using kprobes</a> However, when I try accessing <code>regs->rdi</code> inside my probe, the compiler complains with <pre><code>error: ‘struct pt_regs’ has no member named ‘rdi’ </code></pre> During my module initialization, I run this check with no problems: <pre><code>#ifndef CONFIG_X86_64 printk(KERN_ALERT "Error: this module only supports x86_64!\n"); return -EINVAL; #endif </code></pre> Is there anything else I should be looking at? <code>uname -r</code> returns <code>2.6.32-279.14.1.el6.x86_64.debug</code> Here is a MWE: <pre><code>#include <linux/module.h> #include <linux/kernel.h> #include <linux/kprobes.h> #include <linux/blkdev.h> static int kprobe_test(struct kprobe *p, struct pt_regs *regs) { printk(KERN_INFO "rdi: %p\n", regs->rdi); return 0; } static struct kprobe myprobe = { .pre_handler = NULL, .post_handler = kprobe_test, .fault_handler = NULL, .addr = (kprobe_opcode_t *) generic_make_request, }; int init_module(void) { register_kprobe(&myprobe); return 0; } void cleanup_module(void) { unregister_kprobe(&myprobe); } </code></pre> Which results in: <pre><code>... /home/user/kmod/kprobe_64_mwe/kprobe_mwe.c:7: error: ‘struct pt_regs’ has no member named ‘rdi’ ... </code></pre>
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<linux><kernel><kprobe>
Title
Getting args from kprobe not finding regs->rdi x86_64
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