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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] 6pack: drop redundant locking and refcounting Message-ID: References: <20250923060706.10232-1-dqfext@gmail.com> Precedence: bulk X-Mailing-List: netdev@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: <20250923060706.10232-1-dqfext@gmail.com> On Tue, Sep 23, 2025 at 02:07:06PM +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 > Signed-off-by: Qingfang Deng checkpatch says: WARNING: Reported-by: should be immediately followed by Closes: with a URL to the report Which is relevant here because Google has apparently deleted their search button and is only displaying the AI button. "The email address syzbot+5fd749c74105b0e1b302@syzkaller.appspotmail.com is an automated sender used by ..." Thanks, AI! I can still press enter to do a Google search but there are no results with syzbot ID. I can't find a search button on the syzbot website. Ah. Let's check lore. Hooray! How did we ever survive before lore? https://lore.kernel.org/all/000000000000e8231f0601095c8e@google.com/ Please add the Closes tag and resend. Otherwise it looks good. Thanks! This code was copy and pasted from drivers/net/ppp/ppp_synctty.c btw so that's a similar thing if anyone wants to fix that. KTODO: remove sp_get/put() from ppp_synctty.c regards, dan carpenter