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bh=VEudGuTbI8GghvYngS74lz28bkiQJqXeUNzo7Tr5OoA=; b=BJgiRlz0je11Z1r1LNqL92W3fQ a5OOoj2ob+vV+XocxtjGdUPW5vnwZ9G9KKW/erh/BgetQknKnUYXdKE9iKx/6VxdrBnkm+FA7pWcg 96O8PiVEQ3GgJ+CpXuxSW4KGZ+Dk9tBzllKTEwT7SFKXxVnzfUsoDoH+NjX1NxDkqs8fmzxmpz8tn Bi0sQDjGjh0jmgQxgE7/gGomNqwNm6Gk9Lg0ycVEMSyWn38xepB30Ihk/23dFfZNn5AqJRiSutzbX y1Pey7omE9jMXy+HjVL+Zirk0r5Pq08G3sR/z8nk83Vwtucla6f+jIuHA+EzW/G+Umep7qjBO5FuV 8LOjjCpg==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.96 #2 (Red Hat Linux)) id 1q49kG-00Fbuq-11; Wed, 31 May 2023 00:31:20 +0000 Date: Tue, 30 May 2023 17:31:20 -0700 From: Luis Chamberlain To: Linus Torvalds Cc: Johan Hovold , Lucas De Marchi , Petr Pavlu , gregkh@linuxfoundation.org, rafael@kernel.org, song@kernel.org, lucas.de.marchi@gmail.com, christophe.leroy@csgroup.eu, peterz@infradead.org, rppt@kernel.org, dave@stgolabs.net, willy@infradead.org, vbabka@suse.cz, mhocko@suse.com, dave.hansen@linux.intel.com, colin.i.king@gmail.com, jim.cromie@gmail.com, catalin.marinas@arm.com, jbaron@akamai.com, rick.p.edgecombe@intel.com, yujie.liu@intel.com, david@redhat.com, tglx@linutronix.de, hch@lst.de, patches@lists.linux.dev, linux-modules@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, pmladek@suse.com, prarit@redhat.com, lennart@poettering.net Subject: Re: [PATCH 2/2] module: add support to avoid duplicates early on load Message-ID: References: <6gwjomw6sxxmlglxfoilelswv4hgygqelomevb4k4wrlrk3gtm@wrakbmwztgeu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 24606160007 X-Stat-Signature: izbfubsebksmb8xno6ygz8zds1ik3g83 X-Rspam-User: X-HE-Tag: 1685493104-812523 X-HE-Meta: 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 P9Uj/ja2 tRv8ZfSNCD0j+U8EnVJOHdtRE4eDz+tRhfZy74oyM3JvPVNFcgyrxgc8ELWHPLLWDYLdWo3hUH+7kLz3YNGRO55ei2HE+zQdD5bbVorjxdgGF4cvl43ss3vAMR8Lf2J5IHIWoRE0x9FLMTUlzHhuZVZFkMtKhLs2HJYaoKEMS1/UHrxih19VyeT2TdkrBeY81AR4ShCljgPIU37VoaPWAqOm2a9lm44vnBGTwswibh7Qa/Ej9KARrwhrfXAgyF7l+V/XK1i6tOJt1kUIK0w2QCJ2J7U0cPk8/d6Y2HK9D55JRbvS4F+JL6tVdk+KyetLP4f3Mv47DUp5n0KjmUIHlqTw9V63ZTRwVMaRV5DV0zrRBjWXvdM8YFcvIiyJqb0iMxnLh X-Bogosity: Ham, tests=bogofilter, spamicity=0.000161, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, May 30, 2023 at 09:22:14AM -0700, Luis Chamberlain wrote: > The only thing I can think of is allowing threads other than the > first one to complete before the one that actually loaded the > module. I thought about this race for module auto-loading, see > the comment in kmod_dup_request_announce(), so that just > further delays the completion to other thread with a stupid > queue_work(). That seems more important for module auto-loading > duplicates than for boot finit_module() duplicates. But not sure > if odering matters in the end due to a preemtible kernel and maybe > that concern is hysteria. I think I'm OK to accept this ordering concern as hysteria for now. Luis