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Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , linux-hams@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+5fd749c74105b0e1b302@syzkaller.appspotmail.com Subject: Re: [PATCH net-next v2] 6pack: drop redundant locking and refcounting Message-ID: References: <20250925051059.26876-1-dqfext@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20250925051059.26876-1-dqfext@gmail.com> On Thu, Sep 25, 2025 at 01:10:59PM +0800, Qingfang Deng wrote: > The TTY layer already serializes line discipline operations with > tty->ldisc_sem, so the extra disc_data_lock and refcnt in 6pack > are unnecessary. > > Removing them simplifies the code and also resolves a lockdep warning > reported by syzbot. The warning did not indicate a real deadlock, since > the write-side lock was only taken in process context with hardirqs > disabled. > > Reported-by: syzbot+5fd749c74105b0e1b302@syzkaller.appspotmail.com > Closes: https://lore.kernel.org/all/68c858b0.050a0220.3c6139.0d1c.GAE@google.com/ > Signed-off-by: Qingfang Deng > --- > v2: add Closes tag > - https://lore.kernel.org/netdev/20250923060706.10232-1-dqfext@gmail.com/ > Thanks! Reviewed-by: Dan Carpenter regards, dan carpenter