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Date: Fri, 16 Feb 2024 21:57:01 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Imran Khan <imran.f.khan@oracle.com>
Cc: davem@davemloft.net, edumazet@google.com, kuba@kernel.org,
	pabeni@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] connector/cn_proc: make comm length as TASK_COMM_LEN.
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> --- a/include/uapi/linux/cn_proc.h
> +++ b/include/uapi/linux/cn_proc.h
> @@ -136,7 +136,7 @@ struct proc_event {
>  		struct comm_proc_event {
>  			__kernel_pid_t process_pid;
>  			__kernel_pid_t process_tgid;
> -			char           comm[16];
> +			char           comm[TASK_COMM_LEN];
>  		} comm;

No, 16 must remain 16.

This is ABI header, and TASK_COMM_LEN is in sched.h which is NOT ABI
header. This breaks compilation for everyone using it outside of kernel.

TASK_COMM_LEN is probably fixed at this point by countless trace events
but still... unless you've moving TASK_COMM_LEN to uapi/ too, this is
wrong.