linux-stable.git/drivers/net/phy/phy.c, branch v4.9.78

Revert "net: phy: Correctly process PHY_HALTED in phy_stop_machine()"

2017-09-20T06:19:55+00:00

[ Upstream commit ebc8254aeae34226d0bc8fda309fd9790d4dccfe ]

This reverts commit 7ad813f208533cebfcc32d3d7474dc1677d1b09a ("net: phy:
Correctly process PHY_HALTED in phy_stop_machine()") because it is
creating the possibility for a NULL pointer dereference.

David Daney provide the following call trace and diagram of events:

When ndo_stop() is called we call:

 phy_disconnect()
    +---> phy_stop_interrupts() implies: phydev->irq = PHY_POLL;
    +---> phy_stop_machine()
    |      +---> phy_state_machine()
    |              +----> queue_delayed_work(): Work queued.
    +--->phy_detach() implies: phydev->attached_dev = NULL;

Now at a later time the queued work does:

 phy_state_machine()
    +---->netif_carrier_off(phydev->attached_dev): Oh no! It is NULL:

 CPU 12 Unable to handle kernel paging request at virtual address
0000000000000048, epc == ffffffff80de37ec, ra == ffffffff80c7c
Oops[#1]:
CPU: 12 PID: 1502 Comm: kworker/12:1 Not tainted 4.9.43-Cavium-Octeon+ #1
Workqueue: events_power_efficient phy_state_machine
task: 80000004021ed100 task.stack: 8000000409d70000
$ 0   : 0000000000000000 ffffffff84720060 0000000000000048 0000000000000004
$ 4   : 0000000000000000 0000000000000001 0000000000000004 0000000000000000
$ 8   : 0000000000000000 0000000000000000 00000000ffff98f3 0000000000000000
$12   : 8000000409d73fe0 0000000000009c00 ffffffff846547c8 000000000000af3b
$16   : 80000004096bab68 80000004096babd0 0000000000000000 80000004096ba800
$20   : 0000000000000000 0000000000000000 ffffffff81090000 0000000000000008
$24   : 0000000000000061 ffffffff808637b0
$28   : 8000000409d70000 8000000409d73cf0 80000000271bd300 ffffffff80c7804c
Hi    : 000000000000002a
Lo    : 000000000000003f
epc   : ffffffff80de37ec netif_carrier_off+0xc/0x58
ra    : ffffffff80c7804c phy_state_machine+0x48c/0x4f8
Status: 14009ce3        KX SX UX KERNEL EXL IE
Cause : 00800008 (ExcCode 02)
BadVA : 0000000000000048
PrId  : 000d9501 (Cavium Octeon III)
Modules linked in:
Process kworker/12:1 (pid: 1502, threadinfo=8000000409d70000,
task=80000004021ed100, tls=0000000000000000)
Stack : 8000000409a54000 80000004096bab68 80000000271bd300 80000000271c1e00
        0000000000000000 ffffffff808a1708 8000000409a54000 80000000271bd300
        80000000271bd320 8000000409a54030 ffffffff80ff0f00 0000000000000001
        ffffffff81090000 ffffffff808a1ac0 8000000402182080 ffffffff84650000
        8000000402182080 ffffffff84650000 ffffffff80ff0000 8000000409a54000
        ffffffff808a1970 0000000000000000 80000004099e8000 8000000402099240
        0000000000000000 ffffffff808a8598 0000000000000000 8000000408eeeb00
        8000000409a54000 00000000810a1d00 0000000000000000 8000000409d73de8
        8000000409d73de8 0000000000000088 000000000c009c00 8000000409d73e08
        8000000409d73e08 8000000402182080 ffffffff808a84d0 8000000402182080
        ...
Call Trace:
[] netif_carrier_off+0xc/0x58
[] phy_state_machine+0x48c/0x4f8
[] process_one_work+0x158/0x368
[] worker_thread+0x150/0x4c0
[] kthread+0xc8/0xe0
[] ret_from_kernel_thread+0x14/0x1c

The original motivation for this change originated from Marc Gonzales
indicating that his network driver did not have its adjust_link callback
executing with phydev->link = 0 while he was expecting it.

PHYLIB has never made any such guarantees ever because phy_stop() merely just
tells the workqueue to move into PHY_HALTED state which will happen
asynchronously.

Reported-by: Geert Uytterhoeven 
Reported-by: David Daney 
Fixes: 7ad813f20853 ("net: phy: Correctly process PHY_HALTED in phy_stop_machine()")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

phy state machine: failsafe leave invalid RUNNING state

2017-08-11T15:49:35+00:00

[ Upstream commit 811a919135b980bac8009d042acdccf10dc1ef5e ]

While in RUNNING state, phy_state_machine() checks for link changes by
comparing phydev->link before and after calling phy_read_status().
This works as long as it is guaranteed that phydev->link is never
changed outside the phy_state_machine().

If in some setups this happens, it causes the state machine to miss
a link loss and remain RUNNING despite phydev->link being 0.

This has been observed running a dsa setup with a process continuously
polling the link states over ethtool each second (SNMPD RFC-1213
agent). Disconnecting the link on a phy followed by a ETHTOOL_GSET
causes dsa_slave_get_settings() / dsa_slave_get_link_ksettings() to
call phy_read_status() and with that modify the link status - and
with that bricking the phy state machine.

This patch adds a fail-safe check while in RUNNING, which causes to
move to CHANGELINK when the link is gone and we are still RUNNING.

Signed-off-by: Zefir Kurtisi 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net: phy: Correctly process PHY_HALTED in phy_stop_machine()

2017-08-11T15:49:34+00:00

[ Upstream commit 7ad813f208533cebfcc32d3d7474dc1677d1b09a ]

Marc reported that he was not getting the PHY library adjust_link()
callback function to run when calling phy_stop() + phy_disconnect()
which does not indeed happen because we set the state machine to
PHY_HALTED but we don't get to run it to process this state past that
point.

Fix this with a synchronous call to phy_state_machine() in order to have
the state machine actually act on PHY_HALTED, set the PHY device's link
down, turn the network device's carrier off and finally call the
adjust_link() function.

Reported-by: Marc Gonzalez 
Fixes: a390d1f379cf ("phylib: convert state_queue work to delayed_work")
Signed-off-by: Florian Fainelli 
Signed-off-by: Marc Gonzalez 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: phy: add an option to disable EEE advertisement

2017-07-05T12:40:19+00:00

[ Upstream commit d853d145ea3e63387a2ac759aa41d5e43876e561 ]

This patch adds an option to disable EEE advertisement in the generic PHY
by providing a mask of prohibited modes corresponding to the value found in
the MDIO_AN_EEE_ADV register.

On some platforms, PHY Low power idle seems to be causing issues, even
breaking the link some cases. The patch provides a convenient way for these
platforms to disable EEE advertisement and work around the issue.

Signed-off-by: Jerome Brunet 
Tested-by: Yegor Yefremov 
Tested-by: Andreas Färber 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net: phy: fix auto-negotiation stall due to unavailable interrupt

2017-05-03T15:36:37+00:00

[ Upstream commit f555f34fdc586a56204cd16d9a7c104ec6cb6650 ]

The Ethernet link on an interrupt driven PHY was not coming up if the Ethernet
cable was plugged before the Ethernet interface was brought up.

The patch trigger PHY state machine to update link state if PHY was requested to
do auto-negotiation and auto-negotiation complete flag already set.

During power-up cycle the PHY do auto-negotiation, generate interrupt and set
auto-negotiation complete flag. Interrupt is handled by PHY state machine but
doesn't update link state because PHY is in PHY_READY state. After some time
MAC bring up, start and request PHY to do auto-negotiation. If there are no new
settings to advertise genphy_config_aneg() doesn't start PHY auto-negotiation.
PHY continue to stay in auto-negotiation complete state and doesn't fire
interrupt. At the same time PHY state machine expect that PHY started
auto-negotiation and is waiting for interrupt from PHY and it won't get it.

Fixes: 321beec5047a ("net: phy: Use interrupts when available in NOLINK state")
Signed-off-by: Alexander Kochetkov 
Cc: stable  # v4.9+
Tested-by: Roger Quadros 
Tested-by: Alexandre Belloni 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: phy: handle state correctly in phy_stop_machine

2017-05-03T15:36:34+00:00

[ Upstream commit 49d52e8108a21749dc2114b924c907db43358984 ]

If the PHY is halted on stop, then do not set the state to PHY_UP.  This
ensures the phy will be restarted later in phy_start when the machine is
started again.

Fixes: 00db8189d984 ("This patch adds a PHY Abstraction Layer to the Linux Kernel, enabling ethernet drivers to remain as ignorant as is reasonable of the connected PHY's design and operation details.")
Signed-off-by: Nathan Sullivan 
Signed-off-by: Brad Mouring 
Acked-by: Xander Huff 
Acked-by: Kyle Roeschley 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: phy: Avoid deadlock during phy_error()

2017-03-22T11:43:32+00:00

[ Upstream commit eab127717a6af54401ba534790c793ec143cd1fc ]

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 
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: phy: Trigger state machine on state change and not polling.

2016-10-13T16:03:47+00:00

The phy_start() is used to indicate the PHY is now ready to do its
work. The state is changed, normally to PHY_UP which means that both
the MAC and the PHY are ready.

If the phy driver is using polling, when the next poll happens, the
state machine notices the PHY is now in PHY_UP, and kicks off
auto-negotiation, if needed.

If however, the PHY is using interrupts, there is no polling. The phy
is stuck in PHY_UP until the next interrupt comes along. And there is
no reason for the PHY to interrupt.

Have phy_start() schedule the state machine to run, which both speeds
up the polling use case, and makes the interrupt use case actually
work.

This problems exists whenever there is a state change which will not
cause an interrupt. Trigger the state machine in these cases,
e.g. phy_error().

Signed-off-by: Andrew Lunn 
Cc: Kyle Roeschley 
Tested-by: Kyle Roeschley 
Signed-off-by: David S. Miller

Revert "phy: IRQ cannot be shared"

2016-08-25T23:53:47+00:00

This reverts:
  commit 33c133cc7598 ("phy: IRQ cannot be shared")

On hardware with multiple PHY devices hooked up to the same IRQ line, allow
them to share it.

Sergei Shtylyov says:
  "I'm not sure now what was the reason I concluded that the IRQ sharing
  was impossible... most probably I thought that the kernel IRQ handling
  code exited the loop over the IRQ actions once IRQ_HANDLED was returned
  -- which is obviously not so in reality..."

Signed-off-by: Xander Huff 
Signed-off-by: Nathan Sullivan 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-05-15T17:32:48+00:00

The nf_conntrack_core.c fix in 'net' is not relevant in 'net-next'
because we no longer have a per-netns conntrack hash.

The ip_gre.c conflict as well as the iwlwifi ones were cases of
overlapping changes.

Conflicts:
	drivers/net/wireless/intel/iwlwifi/mvm/tx.c
	net/ipv4/ip_gre.c
	net/netfilter/nf_conntrack_core.c

Signed-off-by: David S. Miller