linux-stable.git/drivers/net/phy/phy.c, branch linux-4.12.y

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

2017-09-20T06:22:09+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

net: phy: Correctly process PHY_HALTED in phy_stop_machine()

2017-08-11T15:33:59+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 missing SPEED_14000

2017-06-09T13:53:25+00:00

Fixes: 0d7e2d2166f6 ("IB/ipoib: add get_link_ksettings in ethtool")
Signed-off-by: Joe Perches 
Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

net: phy: fix kernel-doc warnings

2017-06-05T15:28:50+00:00

Fix kernel-doc warnings (typo) in drivers/net/phy/phy.c:

..//drivers/net/phy/phy.c:259: warning: No description found for parameter 'features'
..//drivers/net/phy/phy.c:259: warning: Excess function parameter 'feature' description in 'phy_lookup_setting'

Signed-off-by: Randy Dunlap 
Reviewed-by: Andrew Lunn 
Signed-off-by: David S. Miller

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

2017-04-27T02:39:08+00:00

Signed-off-by: David S. Miller

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

2017-04-26T18:32:00+00:00

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

net: phy: simplify phy_supported_speeds()

2017-04-17T17:25:07+00:00

Simplify the loop in phy_supported_speeds().

Signed-off-by: Russell King 
Signed-off-by: David S. Miller

net: phy: improve phylib correctness for non-autoneg settings

2017-04-17T17:25:07+00:00

phylib has some undesirable behaviour when forcing a link mode through
ethtool.  phylib uses this code:

	idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
			features);

to find an index in the settings table.  phy_find_setting() starts at
index 0, and scans upwards looking for an exact speed and duplex match.
When it doesn't find it, it returns MAX_NUM_SETTINGS - 1, which is
10baseT-Half duplex.

phy_find_valid() then scans from the point (and effectively only checks
one entry) before bailing out, returning MAX_NUM_SETTINGS - 1.

phy_sanitize_settings() then sets ->speed to SPEED_10 and ->duplex to
DUPLEX_HALF whether or not 10baseT-Half is supported or not.  This goes
against all the comments against these functions, and 10baseT-Half may
not even be supported by the hardware.

Rework these functions, introducing a new method of scanning the table.
There are two modes of lookup that phylib wants: exact, and inexact.

- in exact mode, we return either an exact match or failure
- in inexact mode, we return an exact match if it exists, a match at
  the highest speed that is not greater than the requested speed
  (ignoring duplex), or failing that, the lowest supported speed, or
  failure.

The biggest difference is that we always check whether the entry is
supported before further consideration, so all unsupported entries are
not considered as candidates.

This results in arguably saner behaviour, better matches the comments,
and is probably what users would expect.

This becomes important as ethernet speeds increase, PHYs exist which do
not support the 10Mbit speeds, and half-duplex is likely to become
obsolete - it's already not even an option on 10Gbit and faster links.

Signed-off-by: Russell King 
Signed-off-by: David S. Miller

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

2017-04-06T15:24:51+00:00

Mostly simple cases of overlapping changes (adding code nearby,
a function whose name changes, for example).

Signed-off-by: David S. Miller

phy/ethtool: Add missing SPEED_ strings

2017-04-05T13:36:06+00:00

Add all the currently available SPEED_ strings.

Signed-off-by: Joe Perches 
Signed-off-by: David S. Miller