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Biederman" , Kees Cook , chenhuacai@kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC] kthread: Unify kernel_thread() and user_mode_thread() Message-Id: <20230512165309.896e063a9398639250eab264@linux-foundation.org> In-Reply-To: <20230509104127.1997562-1-chenhuacai@loongson.cn> References: <20230509104127.1997562-1-chenhuacai@loongson.cn> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Stat-Signature: 96rw4p3wnzxchzz8so73yp8ttoqrerbb X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 956A640010 X-Rspam-User: X-HE-Tag: 1683935591-587925 X-HE-Meta: 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 PgRFQxcc PAiMoHXBoHr3Q0zQNT5xP5CsN5fHE5e6Z1aOKbxjuCjZG3K/h9nvpg/UFr01x/aPyi5K7mZnFTR1XzRISTQK4GPxT2NX9O3zFU2YPzhu4+WG1UUDh/Pyhli6SAS9jLw3VVPokaHI6m/l/5n62SEeIau07qKp70XdCQK1iW2wW042VoHe/TbtMmxMtIVgykVsBhEml6FPJW8iRGkubNZTvuW1KmNU4seq1iEoUelqc40MTanX6mlFNmW1KihlK179k4Izn7/yRaMheSKgVmTW65nMM6+p9Igz1027TwVUAeSVxiCzNuyZFfSFOvOtbrabvVr02CnxSLpHZafOWbs/SmHE9G3aV/vOw6CjXbWtt9VVeigA= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 9 May 2023 18:41:27 +0800 Huacai Chen wrote: > Commit 343f4c49f2438d8 ("kthread: Don't allocate kthread_struct for init > and umh") introduces a new function user_mode_thread() for init and umh. > But the name is a bit confusing because init and umh are indeed kernel > threads at creation time, the real difference is "they will become user > processes". So let's unify the kernel_thread() and user_mode_thread() to > kernel_thread() again, and add a new 'user' parameter for init and umh. > > ... > > 5 files changed, 9 insertions(+), 26 deletions(-) > Less code is nice. > -extern pid_t user_mode_thread(int (*fn)(void *), void *arg, unsigned long flags); > + unsigned long flags, int user); `bool user'?