linux-stable.git/drivers/usb/core/hcd.c, branch v3.18

usb: Do not allow usb_alloc_streams on unconfigured devices

2014-11-03T23:26:15+00:00

This commit fixes the following oops:

[10238.622067] scsi host3: uas_eh_bus_reset_handler start
[10240.766164] usb 3-4: reset SuperSpeed USB device number 3 using xhci_hcd
[10245.779365] usb 3-4: device descriptor read/8, error -110
[10245.883331] usb 3-4: reset SuperSpeed USB device number 3 using xhci_hcd
[10250.897603] usb 3-4: device descriptor read/8, error -110
[10251.058200] BUG: unable to handle kernel NULL pointer dereference at  0000000000000040
[10251.058244] IP: [] xhci_check_streams_endpoint+0x91/0x140

[10251.059473] Call Trace:
[10251.059487]  [] xhci_calculate_streams_and_bitmask+0xbc/0x130
[10251.059520]  [] xhci_alloc_streams+0x10f/0x5a0
[10251.059548]  [] ? check_preempt_curr+0x75/0xa0
[10251.059575]  [] ? ttwu_do_wakeup+0x2c/0x100
[10251.059601]  [] ? ttwu_do_activate.constprop.111+0x66/0x70
[10251.059635]  [] usb_alloc_streams+0xab/0xf0
[10251.059662]  [] uas_configure_endpoints+0x128/0x150 [uas]
[10251.059694]  [] uas_post_reset+0x3c/0xb0 [uas]
[10251.059722]  [] usb_reset_device+0x1b9/0x2a0
[10251.059749]  [] uas_eh_bus_reset_handler+0xb2/0x190 [uas]
[10251.059781]  [] scsi_try_bus_reset+0x53/0x110
[10251.059808]  [] scsi_eh_bus_reset+0xf7/0x270


The problem is the following call sequence (simplified):

1) usb_reset_device
2)  usb_reset_and_verify_device
2)   hub_port_init
3)    hub_port_finish_reset
3)     xhci_discover_or_reset_device
        This frees xhci->devs[slot_id]->eps[ep_index].ring for all eps but 0
4)    usb_get_device_descriptor
       This fails
5)   hub_port_init fails
6)  usb_reset_and_verify_device fails, does not restore device config
7)  uas_post_reset
8)   xhci_alloc_streams
      NULL deref on the free-ed ring

This commit fixes this by not allowing usb_alloc_streams to continue if
the device is not configured.

Note that we do allow usb_free_streams to continue after a (logical)
disconnect, as it is necessary to explicitly free the streams at the xhci
controller level.

Cc: stable@vger.kernel.org
Signed-off-by: Hans de Goede 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: hcd: add generic PHY support

2014-09-29T15:54:02+00:00

Add the generic PHY support, analogous to the USB PHY support. Intended it to be
used with the PCI EHCI/OHCI drivers and the xHCI platform driver.

Signed-off-by: Sergei Shtylyov 
Signed-off-by: Yoshihiro Shimoda 
Signed-off-by: Greg Kroah-Hartman

usb: rename phy to usb_phy in HCD

2014-09-29T15:52:59+00:00

The USB PHY member of the HCD structure is renamed to 'usb_phy' and
modifications are done in all drivers accessing it.
This is in preparation to adding the generic PHY support.

Signed-off-by: Antoine Tenart 
[Sergei: added missing 'drivers/usb/misc/lvstest.c' file, resolved rejects,
updated changelog.]
Signed-off-by: Sergei Shtylyov 
Acked-by: Alan Stern 
Acked-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb: Add LED triggers for USB activity

2014-09-25T15:05:12+00:00

With this patch, USB activity can be signaled by blinking a LED. There
are two triggers, one for activity on USB host and one for USB gadget.

Both triggers should work with all host/device controllers. Tested only
with musb.

Performace: I measured performance overheads on ARM Cortex-A8 (TI
AM335x) running on 600 MHz.

Duration of usb_led_activity():
- with no LED attached to the trigger:        2 ± 1 µs
- with one GPIO LED attached to the trigger:  2 ± 1 µs or 8 ± 2 µs (two peaks in histogram)

Duration of functions calling usb_led_activity() (with this patch
applied and no LED attached to the trigger):
- __usb_hcd_giveback_urb():    10 - 25 µs
- usb_gadget_giveback_request(): 2 - 6 µs

Signed-off-by: Michal Sojka 
Acked-by: Felipe Balbi 
Tested-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb: hub: rename khubd to hub_wq in documentation and comments

2014-09-24T05:33:19+00:00

USB hub has started to use a workqueue instead of kthread. Let's update
the documentation and comments here and there.

This patch mostly just replaces "khubd" with "hub_wq". There are only few
exceptions where the whole sentence was updated. These more complicated
changes can be found in the following files:

	   Documentation/usb/hotplug.txt
	   drivers/net/usb/usbnet.c
	   drivers/usb/core/hcd.c
	   drivers/usb/host/ohci-hcd.c
	   drivers/usb/host/xhci.c

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: hub: rename usb_kick_khubd() to usb_kick_hub_wq()

2014-09-24T05:33:19+00:00

USB hub started to use a workqueue instead of kthread. Let's make it clear from
the function names.

Signed-off-by: Petr Mladek 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: Fixed a few typos

2014-09-24T05:15:18+00:00

Fixed typos in comments of various drivers/usb files

Signed-off-by: Mickael Maison 
Acked-by: Felipe Balbi 
Signed-off-by: Greg Kroah-Hartman

usb-core: Remove Fix mes in file hcd.c

2014-07-18T23:18:11+00:00

I am removing two fix mes in this file as after dicussing then it  seems
there is no reason to check against Null for usb_device as it can never
be NULL and this is check is therefore not needed.

Signed-off-by: Nicholas Krause 
Acked-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

usb: introduce port status lock

2014-05-27T23:51:50+00:00

In general we do not want khubd to act on port status changes that are
the result of in progress resets or USB runtime PM operations.
Specifically port power control testing has been able to trigger an
unintended disconnect in hub_port_connect_change(), paraphrasing:

	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
	    udev->state != USB_STATE_NOTATTACHED) {
		if (portstatus & USB_PORT_STAT_ENABLE) {
			/* Nothing to do */
		} else if (udev->state == USB_STATE_SUSPENDED &&
				udev->persist_enabled) {
			...
		} else {
			/* Don't resuscitate */;
		}
	}

...by falling to the "Don't resuscitate" path or missing
USB_PORT_STAT_CONNECTION because usb_port_resume() was in the middle of
modifying the port status.

So, we want a new lock to hold off khubd for a given port while the
child device is being suspended, resumed, or reset.  The lock ordering
rules are now usb_lock_device() => usb_lock_port().  This is mandated by
the device core which may hold the device_lock on the usb_device before
invoking usb_port_{suspend|resume} which in turn take the status_lock on
the usb_port.  We attempt to hold the status_lock for the duration of a
port_event() run, and drop/re-acquire it when needing to take the
device_lock.  The lock is also dropped/re-acquired during
hub_port_reconnect().

This patch also deletes hub->busy_bits as all use cases are now covered
by port PM runtime synchronization or the port->status_lock and it
pushes down usb_device_lock() into usb_remote_wakeup().

Acked-by: Alan Stern 
Signed-off-by: Dan Williams 
Signed-off-by: Greg Kroah-Hartman

usb: assign default peer ports for root hubs

2014-05-27T23:38:52+00:00

Assume that the peer of a superspeed port is the port with the same id
on the shared_hcd root hub.  This identification scheme is required of
external hubs by the USB3 spec [1].  However, for root hubs, tier mismatch
may be in effect [2].  Tier mismatch can only be enumerated via platform
firmware.  For now, simply perform the nominal association.

A new lock 'usb_port_peer_mutex' is introduced to synchronize port
device add/remove with peer lookups.  It protects peering against
changes to hcd->shared_hcd, hcd->self.root_hub, hdev->maxchild, and
port_dev->child pointers.

[1]: usb 3.1 section 10.3.3
[2]: xhci 1.1 appendix D

Cc: Alan Stern 
[alan: usb_port_peer_mutex locking scheme]
Acked-by: Alan Stern 
Signed-off-by: Dan Williams 
Signed-off-by: Greg Kroah-Hartman