linux-kernel - RE: [PATCH net-next] r8152: use mutex for hw settings

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: <0835B3720019904CB8F7AA43166CEEB2EC397B@RTITMBSTEMP01.realtek.com.tw>
Date:	Thu, 9 Oct 2014 07:59:35 +0000
From:	Hayes Wang <hayeswang@...ltek.com>
To:	David Miller <davem@...emloft.net>
CC:	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	nic_swsd <nic_swsd@...ltek.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-usb@...r.kernel.org" <linux-usb@...r.kernel.org>
Subject: RE: [PATCH net-next] r8152: use mutex for hw settings

 David Miller [mailto:davem@...emloft.net] 
> Sent: Thursday, October 09, 2014 3:45 AM
[..]
> I think a much simpler fix is to take rtnl_lock() in the workqueue
> function and suspend/resume ops.
> 
> Every other place you are adding the mutex already holds the RTNL
> mutex.

If I use the rtnl_lock(), I get a dead lock when enabling autosuspend.

Case 1:
   autosuspend before calling open.
   rtnl_lock()
   call open
   try to autoresume and rtl8152_resume is called.
   dead lock occurs.

Case 2:
   autosuspend occurs.
   rtnl_lock()
   call close
   try to autoresume and rtl8152_resume is called.
   dead lock occurs.
 
Best Regards,
Hayes
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/