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Date: Fri, 19 Apr 2024 23:09:24 -0700
In-Reply-To: <20240420060919.62280-1-aha310510@gmail.com>
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Subject: Re: [syzbot] [hams?] possible deadlock in serial8250_console_write
From: syzbot <syzbot+8e03da5d64bc85098811@syzkaller.appspotmail.com>
To: aha310510@gmail.com
Cc: aha310510@gmail.com, linux-kernel@vger.kernel.org, 
	syzkaller-bugs@googlegroups.com
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> please test deadlock in serial8250_console_write
>
> #syz test git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

This crash does not have a reproducer. I cannot test it.

>
> ---
>  drivers/net/ppp/ppp_async.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ppp/ppp_async.c b/drivers/net/ppp/ppp_async.c
> index c33c3db3cc08..d12b8155e839 100644
> --- a/drivers/net/ppp/ppp_async.c
> +++ b/drivers/net/ppp/ppp_async.c
> @@ -134,11 +134,11 @@ static struct asyncppp *ap_get(struct tty_struct *tty)
>  {
>  	struct asyncppp *ap;
>  
> -	read_lock(&disc_data_lock);
> +	read_lock_irq(&disc_data_lock);
>  	ap = tty->disc_data;
>  	if (ap != NULL)
>  		refcount_inc(&ap->refcnt);
> -	read_unlock(&disc_data_lock);
> +	read_unlock_irq(&disc_data_lock);
>  	return ap;
>  }
>  
> -- 
> 2.34.1