netdev - Re: bug: mutex_lock() in interrupt conntext via phy

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: <1216681028.7559.993.camel@localhost.localdomain>
Date:	Mon, 21 Jul 2008 17:57:08 -0500
From:	Nate Case <ncase@...-inc.com>
To:	Sebastian Siewior <netdev@...breakpoint.cc>
Cc:	Andy Fleming <afleming@...escale.com>, netdev@...r.kernel.org,
	Li Yang <leoli@...escale.com>,
	Grant Likely <grant.likely@...retlab.ca>,
	Pantelis Antoniou <pantelis.antoniou@...il.com>,
	Vitaly Bordug <vbordug@...mvista.com>, linuxppc-dev@...abs.org
Subject: Re: bug: mutex_lock() in interrupt conntext via phy_stop() in
	gianfar

On Fri, 2008-07-18 at 14:10 +0200, Sebastian Siewior wrote:
> Commit 35b5f6b1a aka [PHYLIB: Locking fixes for PHY I/O potentially sleeping]
> changed the phydev->lock from spinlock into a mutex. Now, the following
> code path got triggered while NFS was unavailable:
> 
[snip]
> |[  194.864733] BUG: sleeping function called from invalid context at /home/bigeasy/git/linux-2.6-powerpc/kernel/mutex.c:87
> |[  194.875529] in_atomic():1, irqs_disabled():0
> |[  194.879805] Call Trace:
> |[  194.882250] [c0383d90] [c0006dd8] show_stack+0x48/0x184 (unreliable)
> |[  194.888649] [c0383db0] [c001e938] __might_sleep+0xe0/0xf4
> |[  194.894069] [c0383dc0] [c025a43c] mutex_lock+0x24/0x3c
> |[  194.899234] [c0383de0] [c019005c] phy_stop+0x20/0x70
> |[  194.904234] [c0383df0] [c018d4ec] stop_gfar+0x28/0xf4
> |[  194.909305] [c0383e10] [c018e8c4] gfar_timeout+0x30/0x60
> |[  194.914638] [c0383e20] [c01fe7c0] dev_watchdog+0xa8/0x144

Hmm..  I'm not sure what the best solution is to this.  Make the
stop_gfar() call happen in a workqueue, and make a similar change to
ucc_geth, fec_mpc52xx, and fs_enet? Modify phy_stop() to do the work in
a workqueue conditionally if in interrupt context?  Between these two
I'd lean toward the latter.

Does anyone have any better ideas?

-- 
Nate Case <ncase@...-inc.com>

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html