Re: [PATCH] kprobes: use DEFINE_DEB UGFS_ATTRIBUTE for the enabled knob

On 18 August 2026 17:10:25 BST, Steven Rostedt <[email protected]> wrote:
>On Tue, 18 Aug 2026 16:17:20 +0100
>Bradley Morgan <[email protected]> wrote:
>
>> On 18 August 2026 03:01:18 BST, [email protected] wrote:
>> >Thank you for your contribution! Sashiko AI review found 1 potential
>> >issue(s) to consider:
>> >- [Low] The 'enabled' debugfs file is created using
>`debugfs_create_file()` instead of `debugfs_create_file_unsafe()` with a
>`DEFINE_DEBUGFS_ATTRIBUTE` struct, leading to redundant proxying and
>overhead.  
>> 
>> [email protected] 
>> 
>> I hate sashiko so damn much, best to wait for review!
>
>I found sashiko to be extremely useful. 
>
>
>> >[ ... ]
>> >  
>> >> -static const struct file_operations fops_kp = {
>> >> -	.read =         read_enabled_file_bool,
>> >> -	.write =        write_enabled_file_bool,
>> >> -	.llseek =	default_llseek,
>> >> -};
>> >> +DEFINE_DEBUGFS_ATTRIBUTE(fops_kp, kprobes_enabled_get,
>> >> +			 kprobes_enabled_set, "%llu\n");
>> >>  
>> >>  static int __init debugfs_kprobe_init(void)
>> >>  {  
>> >
>> >[Severity: Low]
>
>It is even saying this is of "low priority". That means it's more of an
>"FYI".
>
>> >Will this lead to double-proxying for the debugfs file?
>> >
>> >Since DEFINE_DEBUGFS_ATTRIBUTE natively provides debugfs_attr_read and
>> >debugfs_attr_write operations that already include debugfs_file_get()
>and
>> >debugfs_file_put() protection, passing fops_kp to debugfs_create_file()
>> >in debugfs_kprobe_init() will cause the debugfs core to wrap it again:
>> >
>> >kernel/kprobes.c:debugfs_kprobe_init() {
>> >    ...
>> >	debugfs_create_file("enabled", 0600, dir, NULL, &fops_kp);
>> >    ...
>> >}
>> >
>> >Could this use debugfs_create_file_unsafe() instead?
>
>As this isn't a critical path, I don't think we really care here if
>it's wrapped or not. But it's nice to know that it is.
>
>Anyway, I'll let others review this, but it looks fine to me.
>
>-- Steve
>
the fix is a couple of years in the making, heh
Thanks!