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Wed, 07 May 2025 05:54:38 -0700 (PDT) Date: Wed, 7 May 2025 14:54:36 +0200 From: Petr Mladek To: Bhupesh Cc: akpm@linux-foundation.org, kernel-dev@igalia.com, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, oliver.sang@intel.com, lkp@intel.com, laoar.shao@gmail.com, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, arnaldo.melo@gmail.com, alexei.starovoitov@gmail.com, andrii.nakryiko@gmail.com, mirq-linux@rere.qmqm.pl, peterz@infradead.org, willy@infradead.org, david@redhat.com, viro@zeniv.linux.org.uk, keescook@chromium.org, ebiederm@xmission.com, brauner@kernel.org, jack@suse.cz, mingo@redhat.com, juri.lelli@redhat.com, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com Subject: Re: [PATCH v3 3/3] exec: Add support for 64 byte 'tsk->real_comm' Message-ID: References: <20250507110444.963779-1-bhupesh@igalia.com> <20250507110444.963779-4-bhupesh@igalia.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250507110444.963779-4-bhupesh@igalia.com> On Wed 2025-05-07 16:34:44, Bhupesh wrote: > Historically due to the 16-byte length of TASK_COMM_LEN, the > users of 'tsk->comm' are restricted to use a fixed-size target > buffer also of TASK_COMM_LEN for 'memcpy()' like use-cases. > > To fix the same, Linus suggested in [1] that we can add the > following union inside 'task_struct': > union { > char comm[TASK_COMM_LEN]; > char real_comm[REAL_TASK_COMM_LEN]; > }; Nit: IMHO, the prefix "real_" is misleading. The buffer size is still limited and the name might be shrinked. I would suggest something like: char comm_ext[TASK_COMM_EXT_LEN]; or char comm_64[TASK_COMM_64_LEN] > and then modify '__set_task_comm()' to pass 'tsk->real_comm' > to the existing users. Best Regards, Petr