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List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Woradorn Laodhanadhaworn , linux-trace-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, linux-kernel-mentees@lists.linux.dev, Steven Rostedt , Masami Hiramatsu Cc: LKML , Brigham Campbell , Jori Koolstra , Mathieu Desnoyers , Shuah Khan , Shuah Khan References: <20260623145147.12145-1-woradorn.laon@gmail.com> Subject: Re: [PATCH v3] tracing: Use seq_buf for string concatenation Content-Language: en-GB, de-DE From: Markus Elfring In-Reply-To: <20260623145147.12145-1-woradorn.laon@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:TFiC94XlxxqZbGdb/y0wk5frxVrXTtU05fENh0OowrVa8K9pe8u QtadBkms3J9BH2F2OZbXKcwFP9m0nBHFFsYe/dmzHELGntnSv7fr8HrFX4MQbHw3UabxIvn j9Zeuwqyh3PuA6/IO4h6Oy9P3fiixSjPlU1hHTnQjWdW8UiLmKByr+hwzUEX0cVSXwfNbOM gdP8oT8JBx9r0CwKd1dDg== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:bGMsl0RDInQ=;s6ChLshfZgchcskk+rGquto+txl 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-4501,13 +4502,20 @@ extern struct trace_event_call *__start_ftrace_e= vents[]; =E2=80=A6 > static __init int setup_trace_event(char *str) > { > - if (bootup_event_buf[0] !=3D '\0') > - strlcat(bootup_event_buf, ",", COMMAND_LINE_SIZE); > + if (seq_buf_used(&bootup_event_seq) > 0) > + seq_buf_puts(&bootup_event_seq, ","); =E2=80=A6 I suggest to use the function =E2=80=9Cseq_buf_putc=E2=80=9D instead at th= is source code place. https://elixir.bootlin.com/linux/v7.1.1/source/lib/seq_buf.c#L203-L221 Is there a need for corresponding error detection? Regards, Markus