When using the remove sysfs file, the device configuration is set to -1
(unconfigured). This eventually unbind drivers with the bandwidth_mutex
held. Some drivers may call functions that hold said mutex, like
usb_reset_device. This is the case for rtl8187, for example. This will
lead to the same process holding the mutex twice, which deadlocks.
Besides, according to Alan Stern:
"The deadlock problem probably could be handled somehow, but there's a
separate issue: Until the usb_disable_device call finishes unbinding
the drivers, the drivers are free to continue using their allocated
bandwidth. We musn't change the bandwidth allocations until after the
unbinding is done. So this patch is indeed necessary."
Unbinding the driver before holding the bandwidth_mutex solves the
problem. If any operation after that fails, drivers are not bound again.
But that would be a problem anyway that the user may solve resetting the
device configuration to one that works, just like he would need to do in
most other failure cases.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fake "address-of" expressions that evaluate to NULL generally confuse
readers and can provoke compiler warnings. This patch (as1412)
removes three such fake expressions, using "#ifdef"s in their place.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a race condition in two utility routines
related to the removal/unlinking of urbs from an anchor.
If two threads are concurrently accessing the same anchor,
both could end up with the same urb - thinking they are
the exclusive owner.
Alan Stern pointed out a related issue in
usb_unlink_anchored_urbs:
"The URB isn't removed from the anchor until it completes
(as a by-product of completion, in fact), which might not
be for quite some time after the unlink call returns.
In the meantime, the subroutine will keep trying to unlink
it, over and over again."
Cc: stable <stable@kernel.org>
Cc: Oliver Neukum <oneukum@suse.de>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1410) makes a slight change to the strategy used for
choosing a default configuration. Currently we skip configs whose
first interface is RNDIS, if the kernel wasn't built with the
corresponding driver. This risks losing access to the other
interfaces in those configs. In addition, if there is only one config
then we will end up not configuring the device at all.
This changes the logic; now such configurations will be skipped only
if there is at least one other config.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Adam Kropelin <akropel1@rochester.rr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The Logitech Harmony 700 series needs an extra delay during
initialization. This patch adds a USB quirk which enables such a delay
and adds the device to the quirks list.
Signed-off-by: Phil Dibowitz <phil@ipom.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Enable MSI/MSI-X supporting in xhci driver.
Provide the mechanism to fall back using MSI and Legacy IRQs
if MSI-X IRQs register failed.
Signed-off-by: Dong Nguyen <Dong.Nguyen@amd.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>,
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If we use the HCD_LOCAL_MEM flag and dma_declare_coherent_memory() to
enforce the host controller's local memory utilization we also need to
disable native scatter-gather support, otherwise hcd_alloc_coherent() in
map_urb_for_dma() is called with urb->transfer_buffer == NULL, that
triggers a NULL pointer dereference.
We can also consider to add a WARN_ON() and return an error code to
better catch this problem in the future.
At the moment no driver seems to hit this bug, so I should
consider this a low-priority fix.
Signed-off-by: Andrea Righi <arighi@develer.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1386) adds runtime-PM support for PCI-based USB host
controllers. By default autosuspend is disallowed; the user must
enable it by writing "auto" to the controller's power/control sysfs
attribute.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1395) adds code to hcd_pci_suspend() for handling wakeup
races. This is another general race pattern, similar to the "open
vs. unregister" race we're all familiar with. Here, the race is
between suspending a device and receiving a wakeup request from one of
the device's suspended children.
In particular, if a root-hub wakeup is requested at about the same
time as the corresponding USB controller is suspended, and if the
controller is enabled for wakeup, then the controller should either
fail to suspend or else wake right back up again.
During system sleep this won't happen very much, especially since host
controllers generally aren't enabled for wakeup during sleep. However
it is definitely an issue for runtime PM. Something like this will be
needed to prevent the controller from autosuspending while waiting for
a root-hub resume to take place. (That is, in fact, the common case,
for which there is an extra test.)
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1385) adds a "do_wakeup" parameter to the pci_suspend
method used by PCI-based host controller drivers. ehci-hcd in
particular needs to know whether or not to enable wakeup when
suspending a controller. Although that information is currently
available through device_may_wakeup(), when support is added for
runtime suspend this will no longer be true.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1384) moves the resume_common() routine in hcd-pci.c a
little higher in the source file to avoid forward references in an
upcoming patch. It also replaces the "hibernated" argument with a
more general "event" argument, which will be useful when the routine
is called during a runtime resume.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1383) takes the powermac-specific code from the PCI HCD
glue layer and encapsulates it in its own subroutine.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1393) converts several of the single-bit fields in
struct usb_hcd to atomic flags. This is for safety's sake; not all
CPUs can update bitfield values atomically, and these flags are used
in multiple contexts.
The flag fields that are set only during registration or removal can
remain as they are, since non-atomic accesses at those times will not
cause any problems.
(Strictly speaking, the authorized_default flag should become atomic
as well. I didn't bother with it because it gets changed only via
sysfs. It can be done later, if anyone wants.)
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
And audit all the users. None needed the BKL. That was easy
because there was only very few around.
Tested with allmodconfig build on x86-64
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
From: Andi Kleen <ak@linux.intel.com>
The code this is attempting to lock against does not use the BKL,
so it's not needed.
Most likely this code is still broken/racy (Al Viro also thinks so),
but removing the BKL should not make it worse than before.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
With this patch, the LPM capable EHCI host controller can put device
into L1 sleep state which is a mode that can enter/exit quickly, and
reduce power consumption.
Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1391) fixes a problem that can occur when USB host
controller hardware is hot-unplugged. If no interrupts are generated
by the unplug then the HCD may not realize that the controller is
gone, and the subsequent unbind may hang waiting for interrupts that
never arrive.
The solution (for PCI-based controllers) is to call the HCD's
interrupt handler at the start of usb_hcd_pci_remove(). If the
hardware is gone, the handler will realize this when it tries to read
the controller's status register.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1390) fixes a problem that crops up when a UHCI host
controller is unbound from uhci-hcd while there are still some active
URBs. The URBs have to be unlinked when the root hub is unregistered,
and uhci-hcd relies upon root-hub status polls as part of its
unlinking procedure. But usb_hcd_poll_rh_status() won't make those
status calls if hcd->rh_registered is clear, and the flag is cleared
_before_ the unregistration takes place.
Since hcd->rh_registered is used for other things and needs to be
cleared early, the solution is to add a new flag (rh_pollable) and use
it instead. It gets cleared _after_ the root hub is unregistered.
Now that the status polls don't end too soon, we have to make sure
they also don't occur too late -- after the root hub's usb_device
structure or the HCD's private structures are deallocated. Therefore
the patch adds usb_get_device() and usb_put_device() calls to protect
the root hub structure, and it adds an extra del_timer_sync() to
prevent the root-hub timer from causing an unexpected status poll.
This additional complexity would not be needed if the HCD framework
had provided separate stop() and release() callbacks instead of just
stop(). This lack could be fixed at some future time (although it
would require changes to every host controller driver); when that
happens this patch won't be needed any more.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1389) fixes some errors in the failure pathway of
usb_add_hcd(). The actions it takes ought to be exactly the same as
those taken by usb_remove_hcd(), but they aren't.
In one case (removal of the usb_bus_attr_group), the two routines are
brought into agreement by changing usb_remove_hcd(). All the other
discrepancies are fixed by changing usb_add_hcd().
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When an attempt is made to read the interface strings of the Artisman
Watchdog USB dongle (idVendor:idProduct 04b4:0526) an error is written
to the dmesg log (uhci_result_common: failed with status 440000) and the
dongle resets itself, resulting in a disconnect/reconnect loop.
Adding the dongle to the list of devices in quirks.c, with the same
quirk Alan Stern's previous patch for the Saitek Cyborg Gold 3D
joystick, stops the device from resetting and allows it to be used with
no problems.
Signed-off-by: Paul Mortier <mortier@btinternet.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Without this fix, a USB 3.0 port is downgraded to full speed after a port
reset of a configured device. The USB 3.0 terminations will be disabled
permanently, and USB 3.0 devices will always enumerate as full speed
devices, until the host controller is unplugged (if it is an ExpressCard)
or the computer is rebooted.
Fajun Chen traced this traced the speed downgrade issue to the port reset
and the interpretation of port status in USB hub driver code. The hub
code was not testing for the port being a SuperSpeed port, and it fell
through to the else case of Full Speed.
The following patch adds SuperSpeed mapping from the port status, and
fixes the speed downgrade issue.
Reported-by: Fajun Chen <fajun.chen@seagate.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
