linux-kernel - Re: [syzbot] [usb?] INFO: task hung in i2c_tiny_usb

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <8bed5082-0aef-4dee-8239-c3e8aba50f9f@suse.com>
Date: Wed, 14 Jan 2026 09:26:54 +0100
From: Oliver Neukum <oneukum@...e.com>
To: weipeng <coderlogicwei@...il.com>
Cc: anna-maria@...utronix.de, frederic@...nel.org,
 linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org,
 syzkaller-bugs@...glegroups.com, tglx@...utronix.de
Subject: Re: [syzbot] [usb?] INFO: task hung in i2c_tiny_usb_disconnect

Hi,

On 14.01.26 09:11, weipeng wrote:
  
> I got it. It can be solved by using wait_for_completion in the module exit
> function to wait for all the i2c_tiny_usb_release() to be done.

At that point the module unload would potentially take forever,
because you cannot control how long it takes to complete.

> The i2c_del_adapter() will wait for all the users to put the reference of the adapter.

That seems reasonable.

> It is not a good idea. We can't control the users. So the i2c_del_adapter() can wait
> for any time.

Who exactly takes references? I think at this point you have a design issue
with the i2c layer and seems proper to include the linux-i2c list.

	Regards
		Oliver