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smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-c45ff70000001609-08-68df2323b35f Date: Fri, 3 Oct 2025 10:13:02 +0900 From: Byungchul Park To: Jan Kara Cc: linux-kernel@vger.kernel.org, kernel_team@skhynix.com, torvalds@linux-foundation.org, damien.lemoal@opensource.wdc.com, linux-ide@vger.kernel.org, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, will@kernel.org, tglx@linutronix.de, rostedt@goodmis.org, joel@joelfernandes.org, sashal@kernel.org, daniel.vetter@ffwll.ch, duyuyang@gmail.com, johannes.berg@intel.com, tj@kernel.org, tytso@mit.edu, willy@infradead.org, david@fromorbit.com, amir73il@gmail.com, gregkh@linuxfoundation.org, kernel-team@lge.com, linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@kernel.org, minchan@kernel.org, hannes@cmpxchg.org, vdavydov.dev@gmail.com, sj@kernel.org, jglisse@redhat.com, dennis@kernel.org, cl@linux.com, penberg@kernel.org, rientjes@google.com, vbabka@suse.cz, ngupta@vflare.org, linux-block@vger.kernel.org, josef@toxicpanda.com, linux-fsdevel@vger.kernel.org, jlayton@kernel.org, dan.j.williams@intel.com, hch@infradead.org, djwong@kernel.org, dri-devel@lists.freedesktop.org, rodrigosiqueiramelo@gmail.com, melissa.srw@gmail.com, hamohammed.sa@gmail.com, harry.yoo@oracle.com, chris.p.wilson@intel.com, gwan-gyeong.mun@intel.com, max.byungchul.park@gmail.com, boqun.feng@gmail.com, longman@redhat.com, yunseong.kim@ericsson.com, ysk@kzalloc.com, yeoreum.yun@arm.com, netdev@vger.kernel.org, matthew.brost@intel.com, her0gyugyu@gmail.com, corbet@lwn.net, catalin.marinas@arm.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, luto@kernel.org, sumit.semwal@linaro.org, gustavo@padovan.org, christian.koenig@amd.com, andi.shyti@kernel.org, arnd@arndb.de, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, rppt@kernel.org, surenb@google.com, mcgrof@kernel.org, petr.pavlu@suse.com, da.gomez@kernel.org, samitolvanen@google.com, paulmck@kernel.org, frederic@kernel.org, neeraj.upadhyay@kernel.org, joelagnelf@nvidia.com, josh@joshtriplett.org, urezki@gmail.com, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, qiang.zhang@linux.dev, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, chuck.lever@oracle.com, neil@brown.name, okorniev@redhat.com, Dai.Ngo@oracle.com, tom@talpey.com, trondmy@kernel.org, anna@kernel.org, kees@kernel.org, bigeasy@linutronix.de, clrkwllms@kernel.org, mark.rutland@arm.com, ada.coupriediaz@arm.com, kristina.martsenko@arm.com, wangkefeng.wang@huawei.com, broonie@kernel.org, kevin.brodsky@arm.com, dwmw@amazon.co.uk, shakeel.butt@linux.dev, ast@kernel.org, ziy@nvidia.com, yuzhao@google.com, baolin.wang@linux.alibaba.com, usamaarif642@gmail.com, joel.granados@kernel.org, richard.weiyang@gmail.com, geert+renesas@glider.be, tim.c.chen@linux.intel.com, linux@treblig.org, alexander.shishkin@linux.intel.com, lillian@star-ark.net, chenhuacai@kernel.org, francesco@valla.it, guoweikang.kernel@gmail.com, link@vivo.com, jpoimboe@kernel.org, masahiroy@kernel.org, brauner@kernel.org, thomas.weissschuh@linutronix.de, oleg@redhat.com, mjguzik@gmail.com, andrii@kernel.org, wangfushuai@baidu.com, linux-doc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, linux-i2c@vger.kernel.org, linux-arch@vger.kernel.org, linux-modules@vger.kernel.org, rcu@vger.kernel.org, linux-nfs@vger.kernel.org, linux-rt-devel@lists.linux.dev Subject: Re: [PATCH v17 30/47] fs/jbd2: use a weaker annotation in journal handling Message-ID: <20251003011302.GE75385@system.software.com> References: <20251002081247.51255-1-byungchul@sk.com> <20251002081247.51255-31-byungchul@sk.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-Brightmail-Tracker: H4sIAAAAAAAAA02SXUxbZRjH857vVrqclS17B+pFhyGCQ2emeTKNWfTCE02mzo+LLXFr7HFt BoW0g63qEmDIYCMRKrBwOhQKqx20lLWom9KFVelEGKzKoMGVDqxsjJURQod827Is7ubNL/// k9/7XDwcqbQyKZxOf0Q06NXZKkZOyaNJ1u1p28LaF3x9Chgq6qIgNldGwVmXg4Eydx0N19ta EYRjZQjmlywkrJj9LMwt/MXCmtePoDZgJsHRUUTA1C+zCGrGIgycmSyi4L6tAoE0YWFhsvtN WAvdJmD4wT0EtsgqASu1h+Fbq4eBO+0nEXjtxQz8GdkAg7H7DPTUnGZgup2BhmIvDfUWM4IT TS4GauvdFIRtExT0VloJsJw5kXjuEFDj/JmABVsLC+N2iYXlsR0Q+qqGgrboAA09o0M0hK+W 0vBj4a344oNjBDgqJkhw/x0vvCOZ0FjaTEGnt4eCspU5BP6L4wRUtH9PQ6FlngbX7SABvf7f KBj4yUnDueEAAWO3gjR4rvWREKz8B4Fz2srs1giObxxIWFo0I6HEc1Q413uPERZjNxih6tp2 4ZIUYoWSyyOs0ODOF0p+jdKCx54hNHVOEoK7pZwRTkUHCeHmUCcjTPf3s+8+s0/+qkbM1hWI hudfOyjXDoQcZN5J/lhznbEQ1SedQjIO8ztx1VQ39Yj/sFQTCab4NHxpdmo9Z/h0HAwukAne xKdiyX8+nss5kj+fij3DxetFMv8h/jL2NZNgBQ+443SITAwpeRvCS65+9LDYiHvqIutWks/A wdXJ+G9cnFPxd6tcIpbxe7B1YWZ9ZDO/DXf9cJVIeDA/LsNXXJfZh5tuxVfsQaoS8dJjWukx rfS/tgGRLUip0xfkqHXZO7O0Jr3uWNYnuTluFL9c2/Hl/RfR7PX3fYjnkCpJIeSNapW0usBo yvEhzJGqTYqD9ptapUKjNn0mGnIPGPKzRaMPpXKUaovixQdHNUr+kPqIeFgU80TDo5bgZCmF qGJrIM2b9XTzls2RXGlm15NS12I9807KXfRyevUTbULjc3ufKkK7lsPd5fr02T2G9zY0ft7R av5dmTmaX/6R6e7Hx53jvguvNDlfN60Fo/8eOLTXnDwib8p8+62ZZ7uVOQGLZv7T1lD1jYzk qv433M1pF4b7znqwWrZ7n5Eq/SDw0hcqyqhV78ggDUb1f5tAJYS1AwAA X-Brightmail-Tracker: H4sIAAAAAAAAA02Se0xTVxzHPffc3nvp7HLXMbmjiVlacYsRH/ORn84sMyZ6s2TqH1tYjGY0 4842PNMqik8eNhBcZq0rSAtaKHYInSAPFbELwVjjEHlUBYUKmKIgIMZRFArtblkW/efkc76P 3+/8cRgsn5NEM9qUfYIuRZ2kpKSkdPtXObEqVb9mVa53MTzMaibBP5lHQnG1k4K82iIJdFyq QtDvz0PwJmDFYGgMkTBnctMwOd1LQ8jlRlDQacLgrM8i4J+aIAWjN18jMA/6KCgcySJhwvEr AsszKw0jt7bBeH+TBELe5wR0T40hcPiCBPiacxHMFSTC+bI6CgJt7RgKzR0ISge9GIZrRLPe /QSBqyKbgiFjAwaP70O475+g4I75JAXjncUEvKyhwJbtkkCJ1YQgx15NQUFJLQmNA9dp6Byd JaCvwERAVe130O94RkKrsYwQ3yemLkeBtTCHEI9hAsx/NhEw7aik4a69jwRHZgxY2zwSeFph oWF2cDWEbKngrnpOg/eUmYRL4+2Sb8yIf2P4jeQr664QvKFrjuKd55yID8yYED95IQfzBqN4 vTk2gfkTdQf4C61jFD/jf0Dxrikbyf9dxvGn22L5RouX5k/89ZjeuXGXdFOCkKRNF3Qrv46X atq9TpyWyx4sL9JnopKF+SiC4di1XJf1dyLMJLuEa3w9SoaZYj/nenqmcZgjWQVncV8UdSmD 2YsKrq47e974mP2BM/jPUGGWscDVn/TicEjOOhAXqL6H/jM+4u4U+eanYnYZ1xMcEbcxIiu4 P4JMWI5gt3Nl06/mI5+wKq75ym3CiGSW99qW99qWd20bwpUoUpuSnqzWJq1boU/UZKRoD674 OTW5Fomf0nF09vQ1NOnZ1oJYBikXyvi0Jxq5RJ2uz0huQRyDlZGy+Io+jVyWoM44JOhSf9Lt TxL0LUjBkMoo2bdxQryc3aveJyQKQpqg+98lmIjoTKRYs2dg3ZYt3RVXF5d+IexuHWo2NsQ8 +mzRTntwY6ln96nymSW3zPn+tru9U9mukqb9Q3uG7arh6PU7YvLX62/vONb76dsGO2FQJRxZ vnXgcHmUrTUucKZvweUfAx1pNzaHvjx7fO8vH4yUnl0wkeCZenl0A3yvlGnjugaWxt7Y2oBf rFSSeo169TKs06v/BVxfeWGQAwAA X-CFilter-Loop: Reflected On Thu, Oct 02, 2025 at 10:40:56AM +0200, Jan Kara wrote: > On Thu 02-10-25 17:12:30, Byungchul Park wrote: > > jbd2 journal handling code doesn't want jbd2_might_wait_for_commit() > > to be placed between start_this_handle() and stop_this_handle(). So it > > marks the region with rwsem_acquire_read() and rwsem_release(). > > > > However, the annotation is too strong for that purpose. We don't have > > to use more than try lock annotation for that. > > > > rwsem_acquire_read() implies: > > > > 1. might be a waiter on contention of the lock. > > 2. enter to the critical section of the lock. > > > > All we need in here is to act 2, not 1. So trylock version of > > annotation is sufficient for that purpose. Now that dept partially > > relies on lockdep annotaions, dept interpets rwsem_acquire_read() as a > > potential wait and might report a deadlock by the wait. > > > > Replace it with trylock version of annotation. > > > > Signed-off-by: Byungchul Park > > Indeed. Feel free to add: > > Reviewed-by: Jan Kara Thank you, Jan. Byungchul > Honza > > > --- > > fs/jbd2/transaction.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c > > index c7867139af69..b4e65f51bf5e 100644 > > --- a/fs/jbd2/transaction.c > > +++ b/fs/jbd2/transaction.c > > @@ -441,7 +441,7 @@ static int start_this_handle(journal_t *journal, handle_t *handle, > > read_unlock(&journal->j_state_lock); > > current->journal_info = handle; > > > > - rwsem_acquire_read(&journal->j_trans_commit_map, 0, 0, _THIS_IP_); > > + rwsem_acquire_read(&journal->j_trans_commit_map, 0, 1, _THIS_IP_); > > jbd2_journal_free_transaction(new_transaction); > > /* > > * Ensure that no allocations done while the transaction is open are > > -- > > 2.17.1 > > > -- > Jan Kara > SUSE Labs, CR