linux-stable.git/drivers/usb/core, branch v3.18.46 Linux kernel stable tree USB: change bInterval default to 10 ms 2016-10-06T02:40:20+00:00 Alan Stern stern@rowland.harvard.edu 2016-09-16T14:24:26+00:00 8694542801332f0019b6a0f12bdf64a358057804 [ Upstream commit 08c5cd37480f59ea39682f4585d92269be6b1424 ] Some full-speed mceusb infrared transceivers contain invalid endpoint descriptors for their interrupt endpoints, with bInterval set to 0. In the past they have worked out okay with the mceusb driver, because the driver sets the bInterval field in the descriptor to 1, overwriting whatever value may have been there before. However, this approach was never sanctioned by the USB core, and in fact it does not work with xHCI controllers, because they use the bInterval value that was present when the configuration was installed. Currently usbcore uses 32 ms as the default interval if the value in the endpoint descriptor is invalid. It turns out that these IR transceivers don't work properly unless the interval is set to 10 ms or below. To work around this mceusb problem, this patch changes the endpoint-descriptor parsing routine, making the default interval value be 10 ms rather than 32 ms. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Wade Berrier <wberrier@gmail.com> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> 
[ Upstream commit 08c5cd37480f59ea39682f4585d92269be6b1424 ]

Some full-speed mceusb infrared transceivers contain invalid endpoint
descriptors for their interrupt endpoints, with bInterval set to 0.
In the past they have worked out okay with the mceusb driver, because
the driver sets the bInterval field in the descriptor to 1,
overwriting whatever value may have been there before.  However, this
approach was never sanctioned by the USB core, and in fact it does not
work with xHCI controllers, because they use the bInterval value that
was present when the configuration was installed.

Currently usbcore uses 32 ms as the default interval if the value in
the endpoint descriptor is invalid.  It turns out that these IR
transceivers don't work properly unless the interval is set to 10 ms
or below.  To work around this mceusb problem, this patch changes the
endpoint-descriptor parsing routine, making the default interval value
be 10 ms rather than 32 ms.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Wade Berrier <wberrier@gmail.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
USB: avoid left shift by -1 2016-09-12T22:59:55+00:00 Alan Stern stern@rowland.harvard.edu 2016-08-23T19:32:51+00:00 e066faf1b61036126cbc3163fa370d4247e880dc [ Upstream commit 53e5f36fbd2453ad69a3369a1db62dc06c30a4aa ] UBSAN complains about a left shift by -1 in proc_do_submiturb(). This can occur when an URB is submitted for a bulk or control endpoint on a high-speed device, since the code doesn't bother to check the endpoint type; normally only interrupt or isochronous endpoints have a nonzero bInterval value. Aside from the fact that the operation is illegal, it shouldn't matter because the result isn't used. Still, in theory it could cause a hardware exception or other problem, so we should work around it. This patch avoids doing the left shift unless the shift amount is >= 0. The same piece of code has another problem. When checking the device speed (the exponential encoding for interrupt endpoints is used only by high-speed or faster devices), we need to look for speed >= USB_SPEED_SUPER as well as speed == USB_SPEED HIGH. The patch adds this check. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Vittorio Zecca <zeccav@gmail.com> Tested-by: Vittorio Zecca <zeccav@gmail.com> Suggested-by: Bjørn Mork <bjorn@mork.no> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> 
[ Upstream commit 53e5f36fbd2453ad69a3369a1db62dc06c30a4aa ]

UBSAN complains about a left shift by -1 in proc_do_submiturb().  This
can occur when an URB is submitted for a bulk or control endpoint on
a high-speed device, since the code doesn't bother to check the
endpoint type; normally only interrupt or isochronous endpoints have
a nonzero bInterval value.

Aside from the fact that the operation is illegal, it shouldn't matter
because the result isn't used.  Still, in theory it could cause a
hardware exception or other problem, so we should work around it.
This patch avoids doing the left shift unless the shift amount is >= 0.

The same piece of code has another problem.  When checking the device
speed (the exponential encoding for interrupt endpoints is used only
by high-speed or faster devices), we need to look for speed >=
USB_SPEED_SUPER as well as speed == USB_SPEED HIGH.  The patch adds
this check.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Vittorio Zecca <zeccav@gmail.com>
Tested-by: Vittorio Zecca <zeccav@gmail.com>
Suggested-by: Bjørn Mork <bjorn@mork.no>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
usb: hub: Fix unbalanced reference count/memory leak/deadlocks 2016-08-31T23:26:30+00:00 Viresh Kumar viresh.kumar@linaro.org 2016-08-04T20:32:22+00:00 64a45a08814a6b1c2ce563b60cd5896fdbbb596c [ Upstream commit 6bb47e8ab98accb1319bd43c64966340ba3bba9a ] Memory leak and unbalanced reference count: If the hub gets disconnected while the core is still activating it, this can result in leaking memory of few USB structures. This will happen if we have done a kref_get() from hub_activate() and scheduled a delayed work item for HUB_INIT2/3. Now if hub_disconnect() gets called before the delayed work expires, then we will cancel the work from hub_quiesce(), but wouldn't do a kref_put(). And so the unbalance. kmemleak reports this as (with the commit e50293ef9775 backported to 3.10 kernel with other changes, though the same is true for mainline as well): unreferenced object 0xffffffc08af5b800 (size 1024): comm "khubd", pid 73, jiffies 4295051211 (age 6482.350s) hex dump (first 32 bytes): 30 68 f3 8c c0 ff ff ff 00 a0 b2 2e c0 ff ff ff 0h.............. 01 00 00 00 00 00 00 00 00 94 7d 40 c0 ff ff ff ..........}@.... backtrace: [<ffffffc0003079ec>] create_object+0x148/0x2a0 [<ffffffc000cc150c>] kmemleak_alloc+0x80/0xbc [<ffffffc000303a7c>] kmem_cache_alloc_trace+0x120/0x1ac [<ffffffc0006fa610>] hub_probe+0x120/0xb84 [<ffffffc000702b20>] usb_probe_interface+0x1ec/0x298 [<ffffffc0005d50cc>] driver_probe_device+0x160/0x374 [<ffffffc0005d5308>] __device_attach+0x28/0x4c [<ffffffc0005d3164>] bus_for_each_drv+0x78/0xac [<ffffffc0005d4ee0>] device_attach+0x6c/0x9c [<ffffffc0005d42b8>] bus_probe_device+0x28/0xa0 [<ffffffc0005d23a4>] device_add+0x324/0x604 [<ffffffc000700fcc>] usb_set_configuration+0x660/0x6cc [<ffffffc00070a350>] generic_probe+0x44/0x84 [<ffffffc000702914>] usb_probe_device+0x54/0x74 [<ffffffc0005d50cc>] driver_probe_device+0x160/0x374 [<ffffffc0005d5308>] __device_attach+0x28/0x4c Deadlocks: If the hub gets disconnected early enough (i.e. before INIT2/INIT3 are finished and the init_work is still queued), the core may call hub_quiesce() after acquiring interface device locks and it will wait for the work to be cancelled synchronously. But if the work handler is already running in parallel, it may try to acquire the same interface device lock and this may result in deadlock. Fix both the issues by removing the call to cancel_delayed_work_sync(). CC: <stable@vger.kernel.org> #4.4+ Fixes: e50293ef9775 ("USB: fix invalid memory access in hub_activate()") Reported-by: Manu Gautam <mgautam@codeaurora.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> 
[ Upstream commit 6bb47e8ab98accb1319bd43c64966340ba3bba9a ]

Memory leak and unbalanced reference count:

If the hub gets disconnected while the core is still activating it, this
can result in leaking memory of few USB structures.

This will happen if we have done a kref_get() from hub_activate() and
scheduled a delayed work item for HUB_INIT2/3. Now if hub_disconnect()
gets called before the delayed work expires, then we will cancel the
work from hub_quiesce(), but wouldn't do a kref_put(). And so the
unbalance.

kmemleak reports this as (with the commit e50293ef9775 backported to
3.10 kernel with other changes, though the same is true for mainline as
well):

unreferenced object 0xffffffc08af5b800 (size 1024):
  comm "khubd", pid 73, jiffies 4295051211 (age 6482.350s)
  hex dump (first 32 bytes):
    30 68 f3 8c c0 ff ff ff 00 a0 b2 2e c0 ff ff ff  0h..............
    01 00 00 00 00 00 00 00 00 94 7d 40 c0 ff ff ff  ..........}@....
  backtrace:
    [<ffffffc0003079ec>] create_object+0x148/0x2a0
    [<ffffffc000cc150c>] kmemleak_alloc+0x80/0xbc
    [<ffffffc000303a7c>] kmem_cache_alloc_trace+0x120/0x1ac
    [<ffffffc0006fa610>] hub_probe+0x120/0xb84
    [<ffffffc000702b20>] usb_probe_interface+0x1ec/0x298
    [<ffffffc0005d50cc>] driver_probe_device+0x160/0x374
    [<ffffffc0005d5308>] __device_attach+0x28/0x4c
    [<ffffffc0005d3164>] bus_for_each_drv+0x78/0xac
    [<ffffffc0005d4ee0>] device_attach+0x6c/0x9c
    [<ffffffc0005d42b8>] bus_probe_device+0x28/0xa0
    [<ffffffc0005d23a4>] device_add+0x324/0x604
    [<ffffffc000700fcc>] usb_set_configuration+0x660/0x6cc
    [<ffffffc00070a350>] generic_probe+0x44/0x84
    [<ffffffc000702914>] usb_probe_device+0x54/0x74
    [<ffffffc0005d50cc>] driver_probe_device+0x160/0x374
    [<ffffffc0005d5308>] __device_attach+0x28/0x4c

Deadlocks:

If the hub gets disconnected early enough (i.e. before INIT2/INIT3 are
finished and the init_work is still queued), the core may call
hub_quiesce() after acquiring interface device locks and it will wait
for the work to be cancelled synchronously. But if the work handler is
already running in parallel, it may try to acquire the same interface
device lock and this may result in deadlock.

Fix both the issues by removing the call to cancel_delayed_work_sync().

CC: <stable@vger.kernel.org> #4.4+
Fixes: e50293ef9775 ("USB: fix invalid memory access in hub_activate()")
Reported-by: Manu Gautam <mgautam@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
usb: quirks: Add no-lpm quirk for Elan 2016-08-22T16:23:09+00:00 Joseph Salisbury joseph.salisbury@canonical.com 2016-07-07T01:18:51+00:00 6ef4fa7aa0b734e59c57ae5e7ba6446b3dcff4cd [ Upstream commit 25b1f9acc452209ae0fcc8c1332be852b5c52f53 ] BugLink: http://bugs.launchpad.net/bugs/1498667 As reported in BugLink, this device has an issue with Linux Power Management so adding a quirk. This quirk was reccomended by Alan Stern: http://lkml.iu.edu/hypermail/linux/kernel/1606.2/05590.html Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> 
[ Upstream commit 25b1f9acc452209ae0fcc8c1332be852b5c52f53 ]

BugLink: http://bugs.launchpad.net/bugs/1498667

As reported in BugLink, this device has an issue with Linux Power
Management so adding a quirk.  This quirk was reccomended by Alan Stern:

http://lkml.iu.edu/hypermail/linux/kernel/1606.2/05590.html

Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
USB: quirks: Fix another ELAN touchscreen 2016-08-22T16:23:08+00:00 Adrien Vergé adrienverge@gmail.com 2015-11-24T15:02:04+00:00 84aec61c9b852c07b22756264f67c8f771ce7416 [ Upstream commit df36c5bede207f734e4750beb2b14fb892050280 ] Like other buggy models that had their fixes [1], the touchscreen with id 04f3:21b8 from ELAN Microelectronics needs the device-qualifier quirk. Otherwise, it fails to respond, blocks the boot for a random amount of time and pollutes dmesg with: [ 2887.373196] usb 1-5: new full-speed USB device number 41 using xhci_hcd [ 2889.502000] usb 1-5: unable to read config index 0 descriptor/start: -71 [ 2889.502005] usb 1-5: can't read configurations, error -71 [ 2889.654571] usb 1-5: new full-speed USB device number 42 using xhci_hcd [ 2891.783438] usb 1-5: unable to read config index 0 descriptor/start: -71 [ 2891.783443] usb 1-5: can't read configurations, error -71 [1]: See commits c68929f, 876af5d, d749947, a32c99e and dc703ec. Tested-by: Adrien Vergé <adrienverge@gmail.com> Signed-off-by: Adrien Vergé <adrienverge@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> 
[ Upstream commit df36c5bede207f734e4750beb2b14fb892050280 ]

Like other buggy models that had their fixes [1], the touchscreen with
id 04f3:21b8 from ELAN Microelectronics needs the device-qualifier
quirk. Otherwise, it fails to respond, blocks the boot for a random
amount of time and pollutes dmesg with:

[ 2887.373196] usb 1-5: new full-speed USB device number 41 using xhci_hcd
[ 2889.502000] usb 1-5: unable to read config index 0 descriptor/start: -71
[ 2889.502005] usb 1-5: can't read configurations, error -71
[ 2889.654571] usb 1-5: new full-speed USB device number 42 using xhci_hcd
[ 2891.783438] usb 1-5: unable to read config index 0 descriptor/start: -71
[ 2891.783443] usb 1-5: can't read configurations, error -71

[1]: See commits c68929f, 876af5d, d749947, a32c99e and dc703ec.

Tested-by: Adrien Vergé <adrienverge@gmail.com>
Signed-off-by: Adrien Vergé <adrienverge@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
USB: don't free bandwidth_mutex too early 2016-07-12T12:47:15+00:00 Alan Stern stern@rowland.harvard.edu 2016-06-27T14:23:10+00:00 0c0ad079718231c754af426fccdfe35526c88d5d [ Upstream commit ab2a4bf83902c170d29ba130a8abb5f9d90559e1 ] The USB core contains a bug that can show up when a USB-3 host controller is removed. If the primary (USB-2) hcd structure is released before the shared (USB-3) hcd, the core will try to do a double-free of the common bandwidth_mutex. The problem was described in graphical form by Chung-Geol Kim, who first reported it: ================================================= At *remove USB(3.0) Storage sequence <1> --> <5> ((Problem Case)) ================================================= VOLD ------------------------------------|------------ (uevent) ________|_________ |<1> | |dwc3_otg_sm_work | |usb_put_hcd | |peer_hcd(kref=2)| |__________________| ________|_________ |<2> | |New USB BUS #2 | | | |peer_hcd(kref=1) | | | --(Link)-bandXX_mutex| | |__________________| | ___________________ | |<3> | | |dwc3_otg_sm_work | | |usb_put_hcd | | |primary_hcd(kref=1)| | |___________________| | _________|_________ | |<4> | | |New USB BUS #1 | | |hcd_release | | |primary_hcd(kref=0)| | | | | |bandXX_mutex(free) |<- |___________________| (( VOLD )) ______|___________ |<5> | | SCSI | |usb_put_hcd | |peer_hcd(kref=0) | |*hcd_release | |bandXX_mutex(free*)|<- double free |__________________| ================================================= This happens because hcd_release() frees the bandwidth_mutex whenever it sees a primary hcd being released (which is not a very good idea in any case), but in the course of releasing the primary hcd, it changes the pointers in the shared hcd in such a way that the shared hcd will appear to be primary when it gets released. This patch fixes the problem by changing hcd_release() so that it deallocates the bandwidth_mutex only when the _last_ hcd structure referencing it is released. The patch also removes an unnecessary test, so that when an hcd is released, both the shared_hcd and primary_hcd pointers in the hcd's peer will be cleared. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Chung-Geol Kim <chunggeol.kim@samsung.com> Tested-by: Chung-Geol Kim <chunggeol.kim@samsung.com> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> 
[ Upstream commit ab2a4bf83902c170d29ba130a8abb5f9d90559e1 ]

The USB core contains a bug that can show up when a USB-3 host
controller is removed.  If the primary (USB-2) hcd structure is
released before the shared (USB-3) hcd, the core will try to do a
double-free of the common bandwidth_mutex.

The problem was described in graphical form by Chung-Geol Kim, who
first reported it:

=================================================
     At *remove USB(3.0) Storage
     sequence <1> --> <5> ((Problem Case))
=================================================
                                  VOLD
------------------------------------|------------
                                 (uevent)
                            ________|_________
                           |<1>               |
                           |dwc3_otg_sm_work  |
                           |usb_put_hcd       |
                           |peer_hcd(kref=2)|
                           |__________________|
                            ________|_________
                           |<2>               |
                           |New USB BUS #2    |
                           |                  |
                           |peer_hcd(kref=1)  |
                           |                  |
                         --(Link)-bandXX_mutex|
                         | |__________________|
                         |
    ___________________  |
   |<3>                | |
   |dwc3_otg_sm_work   | |
   |usb_put_hcd        | |
   |primary_hcd(kref=1)| |
   |___________________| |
    _________|_________  |
   |<4>                | |
   |New USB BUS #1     | |
   |hcd_release        | |
   |primary_hcd(kref=0)| |
   |                   | |
   |bandXX_mutex(free) |<-
   |___________________|
                               (( VOLD ))
                            ______|___________
                           |<5>               |
                           |      SCSI        |
                           |usb_put_hcd       |
                           |peer_hcd(kref=0)  |
                           |*hcd_release      |
                           |bandXX_mutex(free*)|<- double free
                           |__________________|

=================================================

This happens because hcd_release() frees the bandwidth_mutex whenever
it sees a primary hcd being released (which is not a very good idea
in any case), but in the course of releasing the primary hcd, it
changes the pointers in the shared hcd in such a way that the shared
hcd will appear to be primary when it gets released.

This patch fixes the problem by changing hcd_release() so that it
deallocates the bandwidth_mutex only when the _last_ hcd structure
referencing it is released.  The patch also removes an unnecessary
test, so that when an hcd is released, both the shared_hcd and
primary_hcd pointers in the hcd's peer will be cleared.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Chung-Geol Kim <chunggeol.kim@samsung.com>
Tested-by: Chung-Geol Kim <chunggeol.kim@samsung.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
usb: quirks: Add no-lpm quirk for Acer C120 LED Projector 2016-07-11T15:10:15+00:00 Hans de Goede hdegoede@redhat.com 2016-05-19T15:12:20+00:00 45af7b850fc89e65c8923a0f6c76b3532e6384cb [ Upstream commit 32cb0b37098f4beeff5ad9e325f11b42a6ede56c ] The Acer C120 LED Projector is a USB-3 connected pico projector which takes both its power and video data from USB-3. In combination with some hubs this device does not play well with lpm, so disable lpm for it. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> 
[ Upstream commit 32cb0b37098f4beeff5ad9e325f11b42a6ede56c ]

The Acer C120 LED Projector is a USB-3 connected pico projector which
takes both its power and video data from USB-3.

In combination with some hubs this device does not play well with
lpm, so disable lpm for it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
usb: quirks: Fix sorting 2016-07-11T15:10:09+00:00 Hans de Goede hdegoede@redhat.com 2016-05-19T15:12:19+00:00 9b30454e5b934f8b84cc6953eed1901e05e26fcd [ Upstream commit 81099f97bd31e25ff2719a435b1860fc3876122f ] Properly sort all the entries by vendor id. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> 
[ Upstream commit 81099f97bd31e25ff2719a435b1860fc3876122f ]

Properly sort all the entries by vendor id.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
USB: leave LPM alone if possible when binding/unbinding interface drivers 2016-06-03T15:30:33+00:00 Alan Stern stern@rowland.harvard.edu 2016-04-29T19:25:17+00:00 dc0c1b6e75882998d048a19498b1a219a453531c [ Upstream commit 6fb650d43da3e7054984dc548eaa88765a94d49f ] When a USB driver is bound to an interface (either through probing or by claiming it) or is unbound from an interface, the USB core always disables Link Power Management during the transition and then re-enables it afterward. The reason is because the driver might want to prevent hub-initiated link power transitions, in which case the HCD would have to recalculate the various LPM parameters. This recalculation takes place when LPM is re-enabled and the new parameters are sent to the device and its parent hub. However, if the driver does not want to prevent hub-initiated link power transitions then none of this work is necessary. The parameters don't need to be recalculated, and LPM doesn't need to be disabled and re-enabled. It turns out that disabling and enabling LPM can be time-consuming, enough so that it interferes with user programs that want to claim and release interfaces rapidly via usbfs. Since the usbfs kernel driver doesn't set the disable_hub_initiated_lpm flag, we can speed things up and get the user programs to work by leaving LPM alone whenever the flag isn't set. And while we're improving the way disable_hub_initiated_lpm gets used, let's also fix its kerneldoc. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Matthew Giassa <matthew@giassa.net> CC: Mathias Nyman <mathias.nyman@intel.com> CC: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> 
[ Upstream commit 6fb650d43da3e7054984dc548eaa88765a94d49f ]

When a USB driver is bound to an interface (either through probing or
by claiming it) or is unbound from an interface, the USB core always
disables Link Power Management during the transition and then
re-enables it afterward.  The reason is because the driver might want
to prevent hub-initiated link power transitions, in which case the HCD
would have to recalculate the various LPM parameters.  This
recalculation takes place when LPM is re-enabled and the new
parameters are sent to the device and its parent hub.

However, if the driver does not want to prevent hub-initiated link
power transitions then none of this work is necessary.  The parameters
don't need to be recalculated, and LPM doesn't need to be disabled and
re-enabled.

It turns out that disabling and enabling LPM can be time-consuming,
enough so that it interferes with user programs that want to claim and
release interfaces rapidly via usbfs.  Since the usbfs kernel driver
doesn't set the disable_hub_initiated_lpm flag, we can speed things up
and get the user programs to work by leaving LPM alone whenever the
flag isn't set.

And while we're improving the way disable_hub_initiated_lpm gets used,
let's also fix its kerneldoc.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Matthew Giassa <matthew@giassa.net>
CC: Mathias Nyman <mathias.nyman@intel.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
usb: core: hub: hub_port_init lock controller instead of bus 2016-06-03T15:30:30+00:00 Chris Bainbridge chris.bainbridge@gmail.com 2016-04-25T12:48:38+00:00 42798984faa3d1a83cfc4f4a5ab99f13e6782ef9 [ Upstream commit feb26ac31a2a5cb88d86680d9a94916a6343e9e6 ] The XHCI controller presents two USB buses to the system - one for USB2 and one for USB3. The hub init code (hub_port_init) is reentrant but only locks one bus per thread, leading to a race condition failure when two threads attempt to simultaneously initialise a USB2 and USB3 device: [ 8.034843] xhci_hcd 0000:00:14.0: Timeout while waiting for setup device command [ 13.183701] usb 3-3: device descriptor read/all, error -110 On a test system this failure occurred on 6% of all boots. The call traces at the point of failure are: Call Trace: [<ffffffff81b9bab7>] schedule+0x37/0x90 [<ffffffff817da7cd>] usb_kill_urb+0x8d/0xd0 [<ffffffff8111e5e0>] ? wake_up_atomic_t+0x30/0x30 [<ffffffff817dafbe>] usb_start_wait_urb+0xbe/0x150 [<ffffffff817db10c>] usb_control_msg+0xbc/0xf0 [<ffffffff817d07de>] hub_port_init+0x51e/0xb70 [<ffffffff817d4697>] hub_event+0x817/0x1570 [<ffffffff810f3e6f>] process_one_work+0x1ff/0x620 [<ffffffff810f3dcf>] ? process_one_work+0x15f/0x620 [<ffffffff810f4684>] worker_thread+0x64/0x4b0 [<ffffffff810f4620>] ? rescuer_thread+0x390/0x390 [<ffffffff810fa7f5>] kthread+0x105/0x120 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200 [<ffffffff81ba183f>] ret_from_fork+0x3f/0x70 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200 Call Trace: [<ffffffff817fd36d>] xhci_setup_device+0x53d/0xa40 [<ffffffff817fd87e>] xhci_address_device+0xe/0x10 [<ffffffff817d047f>] hub_port_init+0x1bf/0xb70 [<ffffffff811247ed>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff817d4697>] hub_event+0x817/0x1570 [<ffffffff810f3e6f>] process_one_work+0x1ff/0x620 [<ffffffff810f3dcf>] ? process_one_work+0x15f/0x620 [<ffffffff810f4684>] worker_thread+0x64/0x4b0 [<ffffffff810f4620>] ? rescuer_thread+0x390/0x390 [<ffffffff810fa7f5>] kthread+0x105/0x120 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200 [<ffffffff81ba183f>] ret_from_fork+0x3f/0x70 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200 Which results from the two call chains: hub_port_init usb_get_device_descriptor usb_get_descriptor usb_control_msg usb_internal_control_msg usb_start_wait_urb usb_submit_urb / wait_for_completion_timeout / usb_kill_urb hub_port_init hub_set_address xhci_address_device xhci_setup_device Mathias Nyman explains the current behaviour violates the XHCI spec: hub_port_reset() will end up moving the corresponding xhci device slot to default state. As hub_port_reset() is called several times in hub_port_init() it sounds reasonable that we could end up with two threads having their xhci device slots in default state at the same time, which according to xhci 4.5.3 specs still is a big no no: "Note: Software shall not transition more than one Device Slot to the Default State at a time" So both threads fail at their next task after this. One fails to read the descriptor, and the other fails addressing the device. Fix this in hub_port_init by locking the USB controller (instead of an individual bus) to prevent simultaneous initialisation of both buses. Fixes: 638139eb95d2 ("usb: hub: allow to process more usb hub events in parallel") Link: https://lkml.org/lkml/2016/2/8/312 Link: https://lkml.org/lkml/2016/2/4/748 Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com> Cc: stable <stable@vger.kernel.org> Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sasha.levin@oracle.com> 
[ Upstream commit feb26ac31a2a5cb88d86680d9a94916a6343e9e6 ]

The XHCI controller presents two USB buses to the system - one for USB2
and one for USB3. The hub init code (hub_port_init) is reentrant but
only locks one bus per thread, leading to a race condition failure when
two threads attempt to simultaneously initialise a USB2 and USB3 device:

[    8.034843] xhci_hcd 0000:00:14.0: Timeout while waiting for setup device command
[   13.183701] usb 3-3: device descriptor read/all, error -110

On a test system this failure occurred on 6% of all boots.

The call traces at the point of failure are:

Call Trace:
 [<ffffffff81b9bab7>] schedule+0x37/0x90
 [<ffffffff817da7cd>] usb_kill_urb+0x8d/0xd0
 [<ffffffff8111e5e0>] ? wake_up_atomic_t+0x30/0x30
 [<ffffffff817dafbe>] usb_start_wait_urb+0xbe/0x150
 [<ffffffff817db10c>] usb_control_msg+0xbc/0xf0
 [<ffffffff817d07de>] hub_port_init+0x51e/0xb70
 [<ffffffff817d4697>] hub_event+0x817/0x1570
 [<ffffffff810f3e6f>] process_one_work+0x1ff/0x620
 [<ffffffff810f3dcf>] ? process_one_work+0x15f/0x620
 [<ffffffff810f4684>] worker_thread+0x64/0x4b0
 [<ffffffff810f4620>] ? rescuer_thread+0x390/0x390
 [<ffffffff810fa7f5>] kthread+0x105/0x120
 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200
 [<ffffffff81ba183f>] ret_from_fork+0x3f/0x70
 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200

Call Trace:
 [<ffffffff817fd36d>] xhci_setup_device+0x53d/0xa40
 [<ffffffff817fd87e>] xhci_address_device+0xe/0x10
 [<ffffffff817d047f>] hub_port_init+0x1bf/0xb70
 [<ffffffff811247ed>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff817d4697>] hub_event+0x817/0x1570
 [<ffffffff810f3e6f>] process_one_work+0x1ff/0x620
 [<ffffffff810f3dcf>] ? process_one_work+0x15f/0x620
 [<ffffffff810f4684>] worker_thread+0x64/0x4b0
 [<ffffffff810f4620>] ? rescuer_thread+0x390/0x390
 [<ffffffff810fa7f5>] kthread+0x105/0x120
 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200
 [<ffffffff81ba183f>] ret_from_fork+0x3f/0x70
 [<ffffffff810fa6f0>] ? kthread_create_on_node+0x200/0x200

Which results from the two call chains:

hub_port_init
 usb_get_device_descriptor
  usb_get_descriptor
   usb_control_msg
    usb_internal_control_msg
     usb_start_wait_urb
      usb_submit_urb / wait_for_completion_timeout / usb_kill_urb

hub_port_init
 hub_set_address
  xhci_address_device
   xhci_setup_device

Mathias Nyman explains the current behaviour violates the XHCI spec:

 hub_port_reset() will end up moving the corresponding xhci device slot
 to default state.

 As hub_port_reset() is called several times in hub_port_init() it
 sounds reasonable that we could end up with two threads having their
 xhci device slots in default state at the same time, which according to
 xhci 4.5.3 specs still is a big no no:

 "Note: Software shall not transition more than one Device Slot to the
  Default State at a time"

 So both threads fail at their next task after this.
 One fails to read the descriptor, and the other fails addressing the
 device.

Fix this in hub_port_init by locking the USB controller (instead of an
individual bus) to prevent simultaneous initialisation of both buses.

Fixes: 638139eb95d2 ("usb: hub: allow to process more usb hub events in parallel")
Link: https://lkml.org/lkml/2016/2/8/312
Link: https://lkml.org/lkml/2016/2/4/748
Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>