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[173.79.60.52]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-910406475f5sm151951376d6.9.2026.09.09.15.14.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Sep 2026 15:14:36 -0700 (PDT) Date: Wed, 9 Sep 2026 18:14:33 -0400 From: Gregory Price To: Oleg Nesterov Cc: K Prateek Nayak , Ye Liu , Thomas Gleixner , Peter Zijlstra , "Rafael J. Wysocki" , Andrew Morton , Ingo Molnar , Will Deacon , Boqun Feng , "Paul E. McKenney" , Frederic Weisbecker , Neeraj Upadhyay , Joel Fernandes , Josh Triplett , Uladzislau Rezki , Juri Lelli , Vincent Guittot , Steven Rostedt , Masami Hiramatsu , Josh Poimboeuf , Ye Liu , Michal Hocko , mic@digikod.net, david@kernel.org, linmiaohe@huawei.com, nao.horiguchi@gmail.com, gnoack3000@gmail.com, ljs@kernel.org, sj@kernel.org, rientjes@google.com, shakeel.butt@linux.dev, xu.xin16@zte.com.cn, chengming.zhou@linux.dev, tony.luck@intel.com, reinette.chatre@intel.com, x86@kernel.org, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, pavel@kernel.org, lance.yang@linux.dev, pmladek@suse.com, longman@redhat.com, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, qiang.zhang@linux.dev, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, mark.rutland@arm.com, Dave.Martin@arm.com, james.morse@arm.com, babu.moger@amd.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, rcu@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [PATCH v2 5/8] kernel: convert process/thread iterators to for_each_*_rculock Message-ID: References: <20260907081334.1152889-1-ye.liu@linux.dev> <20260907081334.1152889-6-ye.liu@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Stat-Signature: iboctftp4j1x9e5m1pqzxoao495p7y7n X-Rspamd-Queue-Id: DF27440007 X-Rspamd-Server: rspam07 X-HE-Tag: 1788992078-289586 X-HE-Meta: U2FsdGVkX1/D9A8tG4QZNIkAQQcoPG4vBidUJlovYWX47aaMN+wYKr5+YxwuDahOmM9XMUtlZFa1OmuJclipAdkps0sdjpb/7Jxnhk9XRSa9IPtbiVtjgTedXwUFOLmzsyOVjXfWhhLVOFEEHGHIwm1DSO/cQE1vNKHpN43iS1y7mU494BiDPpcKSy2KoXEinvMK6Ib84Vkw9K30NEYcX6qqZyIbNPC/OeWF9stje6CKjYCfLidqU8necoH6veTVHXcEM0GIWzESdSNmpbISQ2wDkfnZHVbwju5gHL30NTm2LBihDaT0q1nkXP0AF0RiucBBURisNM+cA5Y3kpfQC7wCo4Pkd41VYCbz5cVYCv9PN/EnQGVjKeLP6xdYlC30do94xC5+Q5QJnguicDOdqoUoySL/0cj5Zc6fEgvOctzHqchFax6jbUs+YW3i2fmYXGlnBFgYkTiGeEH6USfUXLWcEH+Ip/DfBM2IkjFGqbtM67HSpqC9mXaJ4WAlsJLqChK7r6EHCl45/jxpgMYpZRY4TDWrOTgef0JvEqrA6L8/NE9ubeALsDeD9Cq9J+G6xVD6LYxxvxx56V9fudKC5IOWDfkPa2xBrDGZkpVnygfwkFE9C6bY9FsiJ4o+P6HPr2Bg4CSk4lni299NTEHtmh9LRytIptZisYWBCpN6+lDqFuFezKTXNsAiJc4FY/WpZQ78eKSTi5LyJoj/6oo6f5f68RH7F1GL0BKufg7tZGdUCFRZAqwiSJtR0SCpehpGvrIftdj7sEWWUU4gxw8AOO7uH8ZeAl3mr0FiQaDmqbgtaitNX6I5zOJ2RWhUv7ZWcrmSiDpDmlJA4XM8sOf7y0dhSvitNU8C5CxLuUt7yqBYyyIm0A0GBbwtJDXi5O+AIeWDG+cw1Tfcb4AQ91jUWsPDw44IjKZI7KImGDjtuXyPPJJI1rfaRA060nh6vxlSFgHgtYg2n4YlqG2tV/l BDcwoduu w6oancdOAgioJEGfUuPbaNzRiPuUu5G0yq7efAzH2X971GYZVnRZ4tTkE72nTim1wClRipnfjXSzm1EVu4q34xSszmkmY3VzerECBwBHpz8gsfk9OQepDVv+uwd6Iqv8Tb/buTPeYIqYBAscjEvyNXkuPLal1bY/cmlBycIBnl13dtRS9LsE9xjIUmq6e5Z/4RMkWtGmY44eAAFWV6yGlLye5nreokPfyqg/95HJg39ZFBG0HJMhtPe14MUJeLWvU8Brzm1BqSc1qa9JLZcpUJZ1Y6Vjch5+3TM12euUS+lfPWhBzxOfvhEcUqNFbfpXlHhri0HHyg1YBnjWhTBJC/8tcXXpHb/SHj5H3BR0FehutIqAiqf+2AmRIhdQgFw3Rmxab79uacbdWCAeLRfitip1KWDVnDu9+GIzo5N80zplPzpenbwJ+hVr3FyrO9qttub9PWKd9dwp8ipK2YVpf0//kVZUnTzgdwZ8j2MoKvhd/Drd8rQKlvZ7iPwXPytrEx7wxscfGdFFX8Nc02igH/IMGFQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Sep 08, 2026 at 08:35:16AM +0200, Oleg Nesterov wrote: > On 09/08, K Prateek Nayak wrote: > > > > On 9/8/2026 3:24 AM, Oleg Nesterov wrote: > > >> This might be my - admittedly shallow - understanding of scoped_guard, > > >> but does scoped guard handle goto correctly? > > > > > > Yes, it does, > > > > > >> and why it's generally discouraged to mix cleanup.h and goto. > > > > > > Hmm, why? I didn't know... > > > > Apparently older GCC would allow subtle bugs with cleanup + goto to slip > > by but clang has always caught those bugs and refused to compile so as > > long as clang builds are happy, things should be good. > > > > Here is an older explanation from Peter: > > https://lore.kernel.org/lkml/20260327154136.GL3739106@noisy.programming.kicks-ass.net/ > > Ah, but in this case the code is buggy, "goto unregister" jumps > into the scope of __free. > > Anyway, I agree that mixing cleanup and goto can make the code > confusing or buggy, but this particular case still looks fine > to me... > Seems jump-out is ok, thanks for the confirmation Peter. I do agree the general improvement is nice, but maybe worth considering taking cleanup.h all the way if we're going to use it - that's all. The improvement is clearly welcome. ~Gregory