phy deadlock -stable backport request

phy deadlock -stable backport request

[Niklas Cassel]

Hello

I would like to request that

commit eab127717a6af54401ba534790c793ec143cd1fc
Author: Florian Fainelli <f.fainelli@gmail.com>
Date:   Fri Jan 20 15:31:52 2017 -0800

    net: phy: Avoid deadlock during phy_error()
   
    phy_error() is called in the PHY state machine workqueue context, and
    calls phy_trigger_machine() which does a cancel_delayed_work_sync() of
    the workqueue we execute from, causing a deadlock situation.
   
    Augment phy_trigger_machine() machine with a sync boolean indicating
    whether we should use cancel_*_sync() or just cancel_*_work().
   
    Fixes: 3c293f4e08b5 ("net: phy: Trigger state machine on state change and not polling.")
    Reported-by: Russell King <rmk+kernel@armlinux.org.uk>
    Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
    Signed-off-by: David S. Miller <davem@davemloft.net>

 drivers/net/phy/phy.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)


would be backported to stable branch v4.9.

I've seen this deadlock happen on v4.9.x


Regards,
Niklas

Re: phy deadlock -stable backport request

[David Miller]

From: Niklas Cassel <niklas.cassel@axis.com>
Date: Mon, 27 Feb 2017 14:56:31 +0100

> I would like to request that
> 
> commit eab127717a6af54401ba534790c793ec143cd1fc
> Author: Florian Fainelli <f.fainelli@gmail.com>
> Date:   Fri Jan 20 15:31:52 2017 -0800
> 
>     net: phy: Avoid deadlock during phy_error()
 ...
> would be backported to stable branch v4.9.
> 
> I've seen this deadlock happen on v4.9.x

Ok, queued up.