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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 In-Reply-To: X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: k0knV9sBER0BlBuHGwtfXiir6hBNPqxA-O-1gVzM4sk_1788849340 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 883FF40006 X-Stat-Signature: 69ma85xjq3gad9tzroje6y3bybpfa4gu X-HE-Tag: 1788849351-535443 X-HE-Meta: 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 5kS5YI4u 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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... Oleg.