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

net: phy: Fix PHY unbind crash

2017-08-11T15:49:37+00:00

commit 7b9a88a390dacb37b051a7b09b9a08f546edf5eb upstream.

The PHY library does not deal very well with bind and unbind events. The first
thing we would see is that we were not properly canceling the PHY state machine
workqueue, so we would be crashing while dereferencing phydev->drv since there
is no driver attached anymore.

Suggested-by: Russell King 
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

net: phy: Do not perform software reset for Generic PHY

2017-08-07T01:59:42+00:00

commit 0878fff1f42c18e448ab5b8b4f6a3eb32365b5b6 upstream.

The Generic PHY driver is a catch-all PHY driver and it should preserve
whatever prior initialization has been done by boot loader or firmware
agents. For specific PHY device configuration it is expected that a
specialized PHY driver would take over that role.

Resetting the generic PHY was a bad idea that has lead to several
complaints and downstream workarounds e.g: in OpenWrt/LEDE so restore
the behavior prior to 87aa9f9c61ad ("net: phy: consolidate PHY
reset in phy_init_hw()").

Reported-by: Felix Fietkau 
Fixes: 87aa9f9c61ad ("net: phy: consolidate PHY reset in phy_init_hw()")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

net: phy: use boolean dt properties for eee broken modes

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

[ Upstream commit 57f3986231bb2c69a55ccab1d2b30a00818027ac ]

The patches regarding eee-broken-modes was merged before all people
involved could find an agreement on the best way to move forward.

While we agreed on having a DT property to mark particular modes as broken,
the value used for eee-broken-modes mapped the phy register in very direct
way. Because of this, the concern is that it could be used to implement
configuration policies instead of describing a broken HW.

In the end, having a boolean property for each mode seems to be preferred
over one bit field value mapping the register (too) directly.

Cc: Florian Fainelli 
Signed-off-by: Jerome Brunet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net: phy: fix sign type error in genphy_config_eee_advert

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

[ Upstream commit 3bb9ab63276696988d8224f52db20e87194deb4b ]

In genphy_config_eee_advert, the return value of phy_read_mmd_indirect is
checked to know if the register could be accessed but the result is
assigned to a 'u32'.
Changing to 'int' to correctly get errors from phy_read_mmd_indirect.

Fixes: d853d145ea3e ("net: phy: add an option to disable EEE advertisement")
Reported-by: Julia Lawall 
Signed-off-by: Jerome Brunet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
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 PHY module checks and NULL deref in phy_attach_direct()

2017-06-17T04:41:52+00:00

[ Upstream commit 6d9f66ac7fec2a6ccd649e5909806dfe36f1fc25 ]

The Generic PHY drivers gets assigned after we checked that the current
PHY driver is NULL, so we need to check a few things before we can
safely dereference d->driver. This would be causing a NULL deference to
occur when a system binds to the Generic PHY driver. Update
phy_attach_direct() to do the following:

- grab the driver module reference after we have assigned the Generic
  PHY drivers accordingly, and remember we came from the generic PHY
  path

- update the error path to clean up the module reference in case the
  Generic PHY probe function fails

- split the error path involving phy_detacht() to avoid double free/put
  since phy_detach() does all the clean up

- finally, have phy_detach() drop the module reference count before we
  call device_release_driver() for the Generic PHY driver case

Fixes: cafe8df8b9bc ("net: phy: Fix lack of reference count on PHY driver")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net: phy: Fix lack of reference count on PHY driver

2017-06-17T04:41:52+00:00

[ Upstream commit cafe8df8b9bc9aa3dffa827c1a6757c6cd36f657 ]

There is currently no reference count being held on the PHY driver,
which makes it possible to remove the PHY driver module while the PHY
state machine is running and polling the PHY. This could cause crashes
similar to this one to show up:

[   43.361162] BUG: unable to handle kernel NULL pointer dereference at 0000000000000140
[   43.361162] IP: phy_state_machine+0x32/0x490
[   43.361162] PGD 59dc067
[   43.361162] PUD 0
[   43.361162]
[   43.361162] Oops: 0000 [#1] SMP
[   43.361162] Modules linked in: dsa_loop [last unloaded: broadcom]
[   43.361162] CPU: 0 PID: 1299 Comm: kworker/0:3 Not tainted 4.10.0-rc5+ #415
[   43.361162] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS Ubuntu-1.8.2-1ubuntu2 04/01/2014
[   43.361162] Workqueue: events_power_efficient phy_state_machine
[   43.361162] task: ffff880006782b80 task.stack: ffffc90000184000
[   43.361162] RIP: 0010:phy_state_machine+0x32/0x490
[   43.361162] RSP: 0018:ffffc90000187e18 EFLAGS: 00000246
[   43.361162] RAX: 0000000000000000 RBX: ffff8800059e53c0 RCX:
ffff880006a15c60
[   43.361162] RDX: ffff880006782b80 RSI: 0000000000000000 RDI:
ffff8800059e5428
[   43.361162] RBP: ffffc90000187e48 R08: ffff880006a15c40 R09:
0000000000000000
[   43.361162] R10: 0000000000000000 R11: 0000000000000000 R12:
ffff8800059e5428
[   43.361162] R13: ffff8800059e5000 R14: 0000000000000000 R15:
ffff880006a15c40
[   43.361162] FS:  0000000000000000(0000) GS:ffff880006a00000(0000)
knlGS:0000000000000000
[   43.361162] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   43.361162] CR2: 0000000000000140 CR3: 0000000005979000 CR4:
00000000000006f0
[   43.361162] Call Trace:
[   43.361162]  process_one_work+0x1b4/0x3e0
[   43.361162]  worker_thread+0x43/0x4d0
[   43.361162]  ? __schedule+0x17f/0x4e0
[   43.361162]  kthread+0xf7/0x130
[   43.361162]  ? process_one_work+0x3e0/0x3e0
[   43.361162]  ? kthread_create_on_node+0x40/0x40
[   43.361162]  ret_from_fork+0x29/0x40
[   43.361162] Code: 56 41 55 41 54 4c 8d 67 68 53 4c 8d af 40 fc ff ff
48 89 fb 4c 89 e7 48 83 ec 08 e8 c9 9d 27 00 48 8b 83 60 ff ff ff 44 8b
73 98 <48> 8b 90 40 01 00 00 44 89 f0 48 85 d2 74 08 4c 89 ef ff d2 8b

Keep references on the PHY driver module right before we are going to
utilize it in phy_attach_direct(), and conversely when we don't use it
anymore in phy_detach().

Signed-off-by: Mao Wenan 
[florian: rebase, rework commit message]
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller 

Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

phy: Don't increment MDIO bus refcount unless it's a different owner

2016-12-07T18:27:14+00:00

Commit 3e3aaf649416 ("phy: fix mdiobus module safety") fixed the way we
dealt with MDIO bus module reference count, but sort of introduced a
regression in that, if an Ethernet driver registers its own MDIO bus
driver, as is common, we will end up with the Ethernet driver's
module->refnct set to 1, thus preventing this driver from any removal.

Fix this by comparing the network device's device driver owner against
the MDIO bus driver owner, and only if they are different, increment the
MDIO bus module refcount.

Fixes: 3e3aaf649416 ("phy: fix mdiobus module safety")
Signed-off-by: Florian Fainelli 
Signed-off-by: David S. Miller

phy: fix device reference leaks

2016-11-07T18:17:29+00:00

Make sure to drop the reference taken by bus_find_device_by_name()
before returning from phy_connect() and phy_attach().

Note that both function still take a reference to the phy device
through phy_attach_direct().

Fixes: e13934563db0 ("[PATCH] PHY Layer fixup")
Cc: Florian Fainelli 
Signed-off-by: Johan Hovold 
Signed-off-by: David S. Miller

Revert "phy: add support for a reset-gpio specification"

2016-05-20T21:56:59+00:00

Commit da47b4572056 ("phy: add support for a reset-gpio specification")
causes the following xtensa qemu crash according to Guenter Roeck:

[    9.366256] libphy: ethoc-mdio: probed
[    9.367389]  (null): could not attach to PHY
[    9.368555]  (null): failed to probe MDIO bus
[    9.371540] Unable to handle kernel paging request at virtual address 0000001c
[    9.371540]  pc = d0320926, ra = 903209d1
[    9.375358] Oops: sig: 11 [#1]

This reverts commit da47b4572056487fd7941c26f73b3e8815ff712a.

Reported-by: Guenter Roeck 
Signed-off-by: Fabio Estevam 
Acked-by: Florian Fainelli 
Tested-by: Guenter Roeck 
Signed-off-by: David S. Miller