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Peter Anvin" , Jan Kara , Jonathan Corbet , Shuah Khan Subject: Re: [RFC PATCH v1 00/13] exec: add spawn templates for repeated executable startup Message-ID: <202606011254.5FCBD65@keescook> References: <20260528095235.2491226-1-me@linux.beauty> <20260528-madig-fachrichtung-fehlinformation-61117ba640da@brauner> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260528-madig-fachrichtung-fehlinformation-61117ba640da@brauner> X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 611B118000A X-Stat-Signature: 4kj3kg17xc4o11ud7mxxw3zbet7fgjdi X-Rspam-User: X-HE-Tag: 1780343738-461547 X-HE-Meta: U2FsdGVkX19a7tYpzVsyaX1LhJK7ddFCTRvB5F9vqKfGylwEkhAjtTjWXofE1L2qb/TxwZCjAFcaeHhPdgw2Q/ahvkSzu1KooE8jMCZo1EStLFfc47pgfY4f6sQnFU5OPg5WSW3lmCnhwsq/Pc1TiybyLwfIdRd66bP3Tda2sIa0oz52uXmSvM5C3iDWMxUOMUEFM/eV7aITUGtol3GNek7cjszdDtKdAQIZ59aNYmCRWKju3T0BDxd73Eu6xAx4dhbSzcMDovGk0EfQJM/opyZVSiYK7Qn/G0LuanYmSgHbCafsLLVUT8AumVwZpjukBN8s4l1cCz2bi6cFo1218avffQGgEeRzd/+6dPcLtJTpcpScnqhE/KwzUSJB3BG53P+BRFg6Li4JvRA+3vtq7DgCU2WVBj9CjJfWZKO/nQ/Muqs/Yh87uPZaoGBwZwgH2++2oSJV73S0hyz1VYchkmwtbwokj9tvbmAFnJUTl6A1poJ5Z5jL3CMPgESk3WBUr3Nf3lpO/Pcp0zw0yuq/rk+eZ5BzuHCx1NCYbx2M8qQj05nMY8gYEw1tgLw0uHmxpUPItwkwJiqUxeh45QJ3FDc4QZVyyMJOcL8eCk1w9JytYd5+VsyO/LCmg/fRKVe56drLq/PS3ZEm08vIsItnvxTwLE398+ognL0nDm6SvtJbJtdv1YF7ilbOrDtMjEiltQWPcMe3nGf7wtl82o+jKZkbjaXiG/etciCKrnwAws+mXQpkOJaHOxhLgApsq76GAsrx0edlHkeUrXiQz5iYp5/03HQ9xohIi9ox0j6rJMG5DFivYWD8NAjDy9eOjgl80txVdGCqKIZxWDNZwt6eCEgn1eHlM+QVSP5+9k8Nj9rnM4QjtIDPO8AVkf/krfztZUGScDdS7yimITpBE1WbzHhF0MttFSRIK9Z8b6OQGJwEa6eTkri8MpFOOtC7w3M3lC2pBDhDx7LklsYAs1r PQu51ALV EliFlcICumzDos0A7txrdFHZ+WFUH/nfdnzSAmgtfgoVKkICiBfvK6D0AOa88jkUfkqbE1fp9ygD+0zxBh1sz9Ne5wVcdOVjoQASgAe4OKNXtcv5sljuVru1aAJxTsDwOPjc/sQ6hCGLWmJl4wxv5/+narBO5Urz9NLbI0VpieclL6aKevWoQKPvynacex57xktwmscthgN5c1Kz7W41ETpzM5b8DYzPmG1YsivFz4PRfvD5oB8C63oxkqPKmS2/qNNr9xG5xkWa9fIins5ePbzVsJw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, May 28, 2026 at 01:02:53PM +0200, Christian Brauner wrote: > On Thu, May 28, 2026 at 05:52:21PM +0800, Li Chen wrote: > > Hi, > > > > This is an early RFC for an idea that is probably still rough in both the > > UAPI and implementation details. Sorry for the rough edges; I am sending > > it now to check whether this direction is worth pursuing and to get > > feedback on the kernel/userspace boundary. > > The idea of having a builder api for exec isn't all that crazy. But it > should simply be built on top of pidfds and thus pidfs itself instead. > It has all the basic infrastructure in place already. Any implementation > should also allow userspace to implement posix_spawn() on top of it. > > fd = pidfd_open(0, PIDFD_EMPTY /* or better name */) > > pidfd_config(fd, ...) // modeled similar to fsconfig() FWIW, I agree this should be modelled after fsconfig and built on pidfs. Doing so will avoid a bunch of design issues, etc. -Kees -- Kees Cook