Automatic kernel fuzzing revealed a recursive locking violation in
usb-storage:
============================================
WARNING: possible recursive locking detected
5.18.0 #3 Not tainted
--------------------------------------------
kworker/1:3/1205 is trying to acquire lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230
but task is already holding lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230
...
stack backtrace:
CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:2988 [inline]
check_deadlock kernel/locking/lockdep.c:3031 [inline]
validate_chain kernel/locking/lockdep.c:3816 [inline]
__lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053
lock_acquire kernel/locking/lockdep.c:5665 [inline]
lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230
usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109
r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622
usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:545 [inline]
device_remove+0x11f/0x170 drivers/base/dd.c:537
__device_release_driver drivers/base/dd.c:1222 [inline]
device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248
usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627
usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118
usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114
This turned out not to be an error in usb-storage but rather a nested
device reset attempt. That is, as the rtl8712 driver was being
unbound from a composite device in preparation for an unrelated USB
reset (that driver does not have pre_reset or post_reset callbacks),
its ->remove routine called usb_reset_device() -- thus nesting one
reset call within another.
Performing a reset as part of disconnect processing is a questionable
practice at best. However, the bug report points out that the USB
core does not have any protection against nested resets. Adding a
reset_in_progress flag and testing it will prevent such errors in the
future.
Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/
Cc: stable@vger.kernel.org
Reported-and-tested-by: Rondreis <linhaoguo86@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The host needs to tell the device the exit latencies using the SET_SEL
request before device initiated link powermanagement can be enabled.
The exit latency values do not change after enumeration, it's enough
to set them once. So do like Windows 10 and issue the SET_SEL request
once just before setting the configuration.
This is also the sequence described in USB 3.2 specs "9.1.2 Bus
enumeration". SET_SEL is issued once before the Set Configuration
request, and won't be cleared by the Set Configuration,
Set Interface or ClearFeature (STALL) requests.
Only warm reset, hot reset, set Address 0 clears the exit latencies.
See USB 3.2 section 9.4.14 Table 9-10 Device parameters and events
Add udev->lpm_devinit_allow, and set it if SET_SEL was successful.
If not set, then don't try to enable device initiated LPM
We used to issue a SET_SEL request every time lpm is enabled for either
U1 or U2 link states, meaning a SET_SEL was issued twice after every
Set Configuration and Set Interface requests, easily accumulating to
over 15 SET_SEL requets during a USB3 webcam enumeration.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220506161807.3369439-1-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rework the body of usb_maxpacket() and just rely on the
usb_pipe_endpoint() helper function to retrieve the host endpoint
instead of doing it by hand.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20220317035514.6378-10-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that all users of usb_maxpacket() have been migrated to only use
two arguments, remove the third variadic argument which was introduced
for the transition.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20220317035514.6378-9-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a transitional patch with the ultimate goal of changing the
prototype of usb_maxpacket() from:
| static inline __u16
| usb_maxpacket(struct usb_device *udev, int pipe, int is_out)
into:
| static inline u16 usb_maxpacket(struct usb_device *udev, int pipe)
The third argument of usb_maxpacket(): is_out gets removed because it
can be derived from its second argument: pipe using
usb_pipeout(pipe). Furthermore, in the current version,
ubs_pipeout(pipe) is called regardless in order to sanitize the is_out
parameter.
In order to make a smooth change, we first deprecate the is_out
parameter by simply ignoring it (using a variadic function) and will
remove it later, once all the callers get updated.
The body of the function is reworked accordingly and is_out is
replaced by usb_pipeout(pipe). The WARN_ON() calls become unnecessary
and get removed.
Finally, the return type is changed from __u16 to u16 because this is
not a UAPI function.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20220317035514.6378-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no more users for the function.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20211223082432.45653-1-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move the "removable" attribute from USB to core in order to allow it to be
supported by other subsystem / buses. Individual buses that want to support
this attribute can populate the removable property of the device while
enumerating it with the 3 possible values -
- "unknown"
- "fixed"
- "removable"
Leaving the field unchanged (i.e. "not supported") would mean that the
attribute would not show up in sysfs for that device. The UAPI (location,
symantics etc) for the attribute remains unchanged.
Move the "removable" attribute from USB to the device core so it can be
used by other subsystems / buses.
By default, devices do not have a "removable" attribute in sysfs.
If a subsystem or bus driver wants to support a "removable" attribute, it
should call device_set_removable() before calling device_register() or
device_add(), e.g.:
device_set_removable(dev, DEVICE_REMOVABLE);
device_register(dev);
The possible values and the resulting sysfs attribute contents are:
DEVICE_REMOVABLE_UNKNOWN -> "unknown"
DEVICE_REMOVABLE -> "removable"
DEVICE_FIXED -> "fixed"
Convert the USB "removable" attribute to use this new device core
functionality. There should be no user-visible change in the location or
semantics of attribute for USB devices.
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rajat Jain <rajatja@google.com>
Link: https://lore.kernel.org/r/20210524171812.18095-1-rajatja@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Introducing usb_for_each_port(). It works the same way as
usb_for_each_dev(), but instead of going through every USB
device in the system, it walks through the USB ports in the
system.
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210407065555.88110-4-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's been almost twenty years since the interface "private data" pointer
was removed in favour of using the driver-data pointer of struct device.
Let's rename the driver-data parameter of usb_driver_claim_interface()
so that it better reflects how it's used.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210318155406.22399-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB devices cannot perform DMA and hence have no dma_mask set in their
device structure. Therefore importing dmabuf into a USB-based driver
fails, which breaks joining and mirroring of display in X11.
For USB devices, pick the associated USB controller as attachment device.
This allows the DRM import helpers to perform the DMA setup. If the DMA
controller does not support DMA transfers, we're out of luck and cannot
import. Our current USB-based DRM drivers don't use DMA, so the actual
DMA device is not important.
Tested by joining/mirroring displays of udl and radeon under Gnome/X11.
v8:
* release dmadev if device initialization fails (Noralf)
* fix commit description (Noralf)
v7:
* fix use-before-init bug in gm12u320 (Dan)
v6:
* implement workaround in DRM drivers and hold reference to
DMA device while USB device is in use
* remove dev_is_usb() (Greg)
* collapse USB helper into usb_intf_get_dma_device() (Alan)
* integrate Daniel's TODO statement (Daniel)
* fix typos (Greg)
v5:
* provide a helper for USB interfaces (Alan)
* add FIXME item to documentation and TODO list (Daniel)
v4:
* implement workaround with USB helper functions (Greg)
* use struct usb_device->bus->sysdev as DMA device (Takashi)
v3:
* drop gem_create_object
* use DMA mask of USB controller, if any (Daniel, Christian, Noralf)
v2:
* move fix to importer side (Christian, Daniel)
* update SHMEM and CMA helpers for new PRIME callbacks
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 6eb0233ec2 ("usb: don't inherity DMA properties for USB devices")
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org> # v5.10+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210303133229.3288-1-tzimmermann@suse.de
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
They need to specify how memory is to be allocated,
as control messages need to work in contexts that require GFP_NOIO.
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Link: https://lore.kernel.org/r/20200923134348.23862-9-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
New core functions to make sending/receiving USB control messages easier
and saner.
In discussions, it turns out that the large majority of users of
usb_control_msg() do so in potentially incorrect ways. The most common
issue is where a "short" message is received, yet never detected
properly due to "incorrect" error handling.
Handle all of this in the USB core with two new functions to try to make
working with USB control messages simpler.
No more need for dynamic data, messages can be on the stack, and only
"complete" send/receive will work without causing an error.
Link: https://lore.kernel.org/r/20200914153756.3412156-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
snd_usb_pipe_sanity_check() is a great function, so let's move it into
the USB core so that other parts of the kernel, including the USB core,
can call it.
Name it usb_pipe_type_check() to match the existing
usb_urb_ep_type_check() call, which now uses this function.
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Eli Billauer <eli.billauer@gmail.com>
Cc: Emiliano Ingrassia <ingrassia@epigenesys.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Tsoy <alexander@tsoy.me>
Cc: "Geoffrey D. Bennett" <g@b4.vu>
Cc: Jussi Laako <jussi@sonarnerd.net>
Cc: Nick Kossifidis <mickflemm@gmail.com>
Cc: Dmitry Panchenko <dmitry@d-systems.ee>
Cc: Chris Wulff <crwulff@gmail.com>
Cc: Jesus Ramos <jesus-ramos@live.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200914153756.3412156-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB is a HOST/DEVICE protocol, as per the specification and all
documentation. Fix up terms that are not applicable to make things
match up with the terms used through the rest of the USB stack.
Acked-by: Felipe Balbi <balbi@kernel.org>
Link: https://lore.kernel.org/r/20200701171555.3198836-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix kernel-doc warnings in <linux/usb.h>:
../include/linux/usb.h:713: warning: Function parameter or member 'use_generic_driver' not described in 'usb_device'
../include/linux/usb.h:1253: warning: Function parameter or member 'match' not described in 'usb_device_driver'
../include/linux/usb.h:1253: warning: Function parameter or member 'id_table' not described in 'usb_device_driver'
Also drop an extra blank line and fix indentation.
Fixes: 77419aa403 ("USB: Fallback to generic driver when specific driver fails")
Fixes: 88b7381a93 ("USB: Select better matching USB drivers when available")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Bastien Nocera <hadess@hadess.net>
Link: https://lore.kernel.org/r/7014bab2-268c-69f6-7ef5-57fbd45c8b08@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200220132017.GA29262@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If ->probe fails for a device specific driver, ask the driver core to
reprobe us, after having flagged the device for the generic driver to be
forced.
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-6-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that USB device drivers can reuse code from the generic USB device
driver, we need to make sure that they get selected rather than the
generic driver. Add an id_table and match vfunc to the usb_device_driver
struct, which will get used to select a better matching driver at
->probe time.
This is a similar mechanism to that used in the HID drivers, with the
generic driver being selected unless there's a better matching one found
in the registered drivers (see hid_generic_match() in
drivers/hid/hid-generic.c).
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-5-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The kernel currenly has only 2 usb_device_drivers, one generic one, one
that completely replaces the generic one to make USB devices usable over
a network.
Use the newly exported generic driver functions when a driver declares
to want them run, in addition to its own code. This makes it possible to
write drivers that extend the generic USB driver.
Note that this patch is not enough for another driver to automatically
get selected.
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-3-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The usb core is the only major place in the kernel that checks for
a non-NULL device dma_mask to see if a device is DMA capable. This
is generally a bad idea, as all major busses always set up a DMA mask,
even if the device is not DMA capable - in fact bus layers like PCI
can't even know if a device is DMA capable at enumeration time. This
leads to lots of workaround in HCD drivers, and also prevented us from
setting up a DMA mask for platform devices by default last time we
tried.
Replace this guess with an explicit HCD_DMA that is set by drivers that
appear to have DMA support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190816062435.881-4-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The USB buffer allocation code is the only place in the usb core (and in
fact the whole kernel) that uses is_device_dma_capable, while the URB
mapping code uses the uses_dma flag in struct usb_bus. Switch the buffer
allocation to use the uses_dma flag used by the rest of the USB code,
and create a helper in hcd.h that checks this flag as well as the
CONFIG_HAS_DMA to simplify the caller a bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190811080520.21712-3-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core supports dev_groups for individual drivers,
expose that pointer to struct usb_device_driver to make it easier for USB
drivers to also use it.
Yes, users of usb_device_driver are much rare, but there are instances
already that use custom sysfs files, so adding this support will make
things easier for those drivers. usbip is one example, hubs might be
another one.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190806144502.17792-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Now that the driver core supports dev_groups for individual drivers,
expose that pointer to struct usb_driver to make it easier for USB
drivers to also use it.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190806144502.17792-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Clear_TT_Buffer request sent to the hub includes the address of
the LS/FS child device in wValue field. usb_hub_clear_tt_buffer()
uses udev->devnum to set the address wValue. This won't work for
devices connected to xHC.
For other host controllers udev->devnum is the same as the address of
the usb device, chosen and set by usb core. With xHC the controller
hardware assigns the address, and won't be the same as devnum.
Here we add devaddr in "struct usb_device" for
usb_hub_clear_tt_buffer() to use.
Signed-off-by: Jim Lin <jilin@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the big set of USB and PHY driver patches for 5.2-rc1
There is the usual set of:
- USB gadget updates
- PHY driver updates and additions
- USB serial driver updates and fixes
- typec updates and new chips supported
- mtu3 driver updates
- xhci driver updates
- other tiny driver updates
Nothing really interesting, just constant forward progress.
All of these have been in linux-next for a while with no reported
issues. The usb-gadget and usb-serial trees were merged a bit "late",
but both of them had been in linux-next before they got merged here last
Friday.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY updates from Greg KH:
"Here is the big set of USB and PHY driver patches for 5.2-rc1
There is the usual set of:
- USB gadget updates
- PHY driver updates and additions
- USB serial driver updates and fixes
- typec updates and new chips supported
- mtu3 driver updates
- xhci driver updates
- other tiny driver updates
Nothing really interesting, just constant forward progress.
All of these have been in linux-next for a while with no reported
issues. The usb-gadget and usb-serial trees were merged a bit "late",
but both of them had been in linux-next before they got merged here
last Friday"
* tag 'usb-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (206 commits)
USB: serial: f81232: implement break control
USB: serial: f81232: add high baud rate support
USB: serial: f81232: clear overrun flag
USB: serial: f81232: fix interrupt worker not stop
usb: dwc3: Rename DWC3_DCTL_LPM_ERRATA
usb: dwc3: Fix default lpm_nyet_threshold value
usb: dwc3: debug: Print GET_STATUS(device) tracepoint
usb: dwc3: Do core validation early on probe
usb: dwc3: gadget: Set lpm_capable
usb: gadget: atmel: tie wake lock to running clock
usb: gadget: atmel: support USB suspend
usb: gadget: atmel_usba_udc: simplify setting of interrupt-enabled mask
dwc2: gadget: Fix completed transfer size calculation in DDMA
usb: dwc2: Set lpm mode parameters depend on HW configuration
usb: dwc2: Fix channel disable flow
usb: dwc2: Set actual frame number for completed ISOC transfer
usb: gadget: do not use __constant_cpu_to_le16
usb: dwc2: gadget: Increase descriptors count for ISOC's
usb: introduce usb_ep_type_string() function
usb: dwc3: move synchronize_irq() out of the spinlock protected block
...
The syzkaller fuzzer reported a bug in the USB hub driver which turned
out to be caused by a negative runtime-PM usage counter. This allowed
a hub to be runtime suspended at a time when the driver did not expect
it. The symptom is a WARNING issued because the hub's status URB is
submitted while it is already active:
URB 0000000031fb463e submitted while active
WARNING: CPU: 0 PID: 2917 at drivers/usb/core/urb.c:363
The negative runtime-PM usage count was caused by an unfortunate
design decision made when runtime PM was first implemented for USB.
At that time, USB class drivers were allowed to unbind from their
interfaces without balancing the usage counter (i.e., leaving it with
a positive count). The core code would take care of setting the
counter back to 0 before allowing another driver to bind to the
interface.
Later on when runtime PM was implemented for the entire kernel, the
opposite decision was made: Drivers were required to balance their
runtime-PM get and put calls. In order to maintain backward
compatibility, however, the USB subsystem adapted to the new
implementation by keeping an independent usage counter for each
interface and using it to automatically adjust the normal usage
counter back to 0 whenever a driver was unbound.
This approach involves duplicating information, but what is worse, it
doesn't work properly in cases where a USB class driver delays
decrementing the usage counter until after the driver's disconnect()
routine has returned and the counter has been adjusted back to 0.
Doing so would cause the usage counter to become negative. There's
even a warning about this in the USB power management documentation!
As it happens, this is exactly what the hub driver does. The
kick_hub_wq() routine increments the runtime-PM usage counter, and the
corresponding decrement is carried out by hub_event() in the context
of the hub_wq work-queue thread. This work routine may sometimes run
after the driver has been unbound from its interface, and when it does
it causes the usage counter to go negative.
It is not possible for hub_disconnect() to wait for a pending
hub_event() call to finish, because hub_disconnect() is called with
the device lock held and hub_event() acquires that lock. The only
feasible fix is to reverse the original design decision: remove the
duplicate interface-specific usage counter and require USB drivers to
balance their runtime PM gets and puts. As far as I know, all
existing drivers currently do this.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-and-tested-by: syzbot+7634edaea4d0b341c625@syzkaller.appspotmail.com
CC: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By moving one field around in 'struct urb' we reduce the size of the
structure by 8 bytes.
Before the patch on x86_64 the overall size of the structure as reported
by pahole was:
/* size: 192, cachelines: 3, members: 30 */
/* sum members: 184, holes: 2, sum holes: 8 */
After the patch we now have:
/* size: 184, cachelines: 3, members: 30 */
/* last cacheline: 56 bytes */
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When reading an extra descriptor, we need to properly check the minimum
and maximum size allowed, to prevent from invalid data being sent by a
device.
Reported-by: Hui Peng <benquike@gmail.com>
Reported-by: Mathias Payer <mathias.payer@nebelwelt.net>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hui Peng <benquike@gmail.com>
Signed-off-by: Mathias Payer <mathias.payer@nebelwelt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the USB hub core waits for 50 ms after enumerating the
device. This was added to help "some high speed devices" to
enumerate (b789696af8 "[PATCH] USB: relax usbcore reset timings").
On some devices, the time-to-active is important, so we provide
a per-port option to reduce the time to what the USB specification
requires: 10 ms.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The "old" enumeration scheme is considerably faster (it takes
~244ms instead of ~356ms to get the descriptor).
It is currently only possible to use the old scheme globally
(/sys/module/usbcore/parameters/old_scheme_first), which is not
desirable as the new scheme was introduced to increase compatibility
with more devices.
However, in our case, we care about time-to-active for a specific
USB device (which we make the firmware for), on a specific port
(that is pogo-pin based: not a standard USB port). This new
sysfs option makes it possible to use the old scheme on a single
port only.
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB 3.2 specification adds Dual-lane support, doubling the maximum
SuperSpeedPlus data rate from 10Gbps to 20Gbps.
Dual-lane takes into use a second set of rx and tx wires/pins in the
Type-C cable and connector.
Add "rx_lanes" and "tx_lanes" variables to struct usb_device to store
the numer of lanes in use. Number of lanes can be read using the extended
port status hub request that was introduced in USB 3.1.
Extended port status rx and tx lane count are zero based, maximum
lanes supported by non inter-chip (SSIC) USB 3.2 is 2 (dual lane) with
rx and tx lane count symmetric. SSIC devices support asymmetric lanes
up to 4 lanes per direction.
If extended port status is not available then default to one lane.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB SS and SSP hubs provide wHubDelay values on their hub descriptor
which we should inform the USB Device about.
The USB Specification 3.0 explains, on section 9.4.11, how to
calculate the value and how to issue the request. Note that a
USB_REQ_SET_ISOCH_DELAY is valid on all device states (Default,
Address, Configured), we just *chose* to issue it from Address state
right after successfully fetching the USB Device Descriptor.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The URB_NO_FSBR flag has never really been used. It was introduced as
a potential way for UHCI to minimize PCI bus usage (by not attempting
full-speed bulk and control transfers more than once per frame), but
the flag was not set by any drivers.
There's no point in keeping it around. This patch simplifies the API
by removing it. Unfortunately, it does have to be kept as part of the
usbfs ABI, but at least we can document in
include/uapi/linux/usbdevice_fs.h that it doesn't do anything.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no big surprising changes in this cycle, yet not too
boring, either. The biggest change from diffstat POV is the removal
of the legacy OSS driver codes that have been already disabled for a
long time. This will bring a few trivial merge conflicts.
As new features in ASoC side, there are two things: a new AC97 bus
implementation and AMD Stony platform support. Both include the
relevant changes shared with other subsystems, e.g. AC97 MFD changes
and DRM AMD changes.
Some other highlighted topics are:
- A bunch of USB-audio drivers got the hardening against the malicious
device accesses with a new helper code for endpoint sanity check.
- Lots of cleanups for ASoC Intel platform code, including support for
their open source audio firmware.
- Continued ASoC core componentization works.
- Support for scaling MCLK with sample rate in ASoC simple-card.
- Stabler PCM hot-unplug capability, especially for ASoC usages.
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Merge tag 'sound-4.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound updates from Takashi Iwai:
"There are no big surprising changes in this cycle, yet not too boring,
either. The biggest change from diffstat POV is the removal of the
legacy OSS driver codes that have been already disabled for a long
time. This will bring a few trivial merge conflicts.
As new features in ASoC side, there are two things: a new AC97 bus
implementation and AMD Stony platform support. Both include the
relevant changes shared with other subsystems, e.g. AC97 MFD changes
and DRM AMD changes.
Some other highlighted topics are:
- A bunch of USB-audio drivers got the hardening against the
malicious device accesses with a new helper code for endpoint
sanity check
- Lots of cleanups for ASoC Intel platform code, including support
for their open source audio firmware
- Continued ASoC core componentization works
- Support for scaling MCLK with sample rate in ASoC simple-card
- Stabler PCM hot-unplug capability, especially for ASoC usages"
* tag 'sound-4.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (302 commits)
Documentation: sound: hd-audio: notes.rst
ASoC: bcm2835: Support left/right justified and DSP modes
ASoC: bcm2835: Enforce full symmetry
ASoC: bcm2835: Support additional samplerates up to 384kHz
ASoC: bcm2835: Add support for TDM modes
ASoC: add mclk-fs support to audio graph card
ASoC: add mclk-fs to audio graph card binding
ASoC: rt5514: work around link error
ASoC: rt5514: mark PM functions as __maybe_unused
ASoC: rt5663: Check the JD status in the button pushing
ASoC: amd: Modified DMA transfer Mechanism for Playback
ASoC: rt5645: Wait for 400msec before concluding on value of RT5645_VENDOR_ID2
ASoC: sun4i-codec: fixed 32bit audio capture support for H3/H2+
ASoC: da7213: add support for DSP modes
ASoC: sun8i-codec: Add a comment on the LRCK inversion
ASoC: sun8i-codec: Set the BCLK divider
ASoC: rt5663: Delay and retry reading rt5663 ID register
ASoC: amd: use do_div rather than 64 bit division to fix 32 bit builds
ASoC: cs42l56: Fix reset GPIO name in example DT binding
ASoC: rt5514-spi: check irq status to schedule data copy in resume function
...
Here is the big set of USB and PHY driver updates for 4.15-rc1.
There is the usual amount of gadget and xhci driver updates, along with
phy and chipidea enhancements. There's also a lot of SPDX tags and
license boilerplate cleanups as well, which provide some churn in the
diffstat.
Other major thing is the typec code that moved out of staging and into
the "real" part of the drivers/usb/ tree, which was nice to see happen.
All of these have been in linux-next with no reported issues for a
while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY updates from Greg KH:
"Here is the big set of USB and PHY driver updates for 4.15-rc1.
There is the usual amount of gadget and xhci driver updates, along
with phy and chipidea enhancements. There's also a lot of SPDX tags
and license boilerplate cleanups as well, which provide some churn in
the diffstat.
Other major thing is the typec code that moved out of staging and into
the "real" part of the drivers/usb/ tree, which was nice to see
happen.
All of these have been in linux-next with no reported issues for a
while"
* tag 'usb-4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (263 commits)
usb: gadget: f_fs: Fix use-after-free in ffs_free_inst
USB: usbfs: compute urb->actual_length for isochronous
usb: core: message: remember to reset 'ret' to 0 when necessary
USB: typec: Remove remaining redundant license text
USB: typec: add SPDX identifiers to some files
USB: renesas_usbhs: rcar?.h: add SPDX tags
USB: chipidea: ci_hdrc_tegra.c: add SPDX line
USB: host: xhci-debugfs: add SPDX lines
USB: add SPDX identifiers to all remaining Makefiles
usb: host: isp1362-hcd: remove a couple of redundant assignments
USB: adutux: remove redundant variable minor
usb: core: add a new usb_get_ptm_status() helper
usb: core: add a 'type' parameter to usb_get_status()
usb: core: introduce a new usb_get_std_status() helper
usb: core: rename usb_get_status() 'type' argument to 'recip'
usb: core: add Status Type definitions
USB: gadget: Remove redundant license text
USB: gadget: function: Remove redundant license text
USB: gadget: udc: Remove redundant license text
USB: gadget: legacy: Remove redundant license text
...
The biggest thing this release has been the conversion of the AC98 bus
to the driver model, that's been a long time coming so thanks to Robert
Jarzmik for his dedication there. Due to there being some AC97 MFD
there's a few fairly large changes in input and the MFD layer, mainly to
the wm97xx driver.
There's also some drivers/drm changes to support the new AMD Stoney
platform, these are shared with the DRM subsystem and should be being
merged via both.
Within the subsystem the overwhelming bulk of the changes is in the
Intel drivers which continue to need lots of cleanups and fixes, this
release they've also gained support for their open source firmware.
There's also some large changs in the core as Morimoto-san continues to
mirror operations into the component level in preparation for conversion
of drivers to that.
- The AC97 bus has finally caught up with the driver model thanks to
some dedicated and persistent work from Robert Jarzmik.
- Continued work from Morimoto-san on moving us towards being able to
use components for everything.
- Lots of cleanups for the Intel platform code, including support for
their open source audio firmware.
- Support for scaling MCLK with sample rate in simple-card.
- Support for AMD Stoney platform.
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Merge tag 'asoc-v4.15' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v4.15
The biggest thing this release has been the conversion of the AC98 bus
to the driver model, that's been a long time coming so thanks to Robert
Jarzmik for his dedication there. Due to there being some AC97 MFD
there's a few fairly large changes in input and the MFD layer, mainly to
the wm97xx driver.
There's also some drivers/drm changes to support the new AMD Stoney
platform, these are shared with the DRM subsystem and should be being
merged via both.
Within the subsystem the overwhelming bulk of the changes is in the
Intel drivers which continue to need lots of cleanups and fixes, this
release they've also gained support for their open source firmware.
There's also some large changs in the core as Morimoto-san continues to
mirror operations into the component level in preparation for conversion
of drivers to that.
- The AC97 bus has finally caught up with the driver model thanks to
some dedicated and persistent work from Robert Jarzmik.
- Continued work from Morimoto-san on moving us towards being able to
use components for everything.
- Lots of cleanups for the Intel platform code, including support for
their open source audio firmware.
- Support for scaling MCLK with sample rate in simple-card.
- Support for AMD Stoney platform.
Drivers who are interested in the PTM status stype, should use this
new helper to make sure they issue the correct GetStatus message.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new 'type' parameter will allows interested drivers to request
for PTM status or Standard status.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This new helper is a simple wrapper around usb_get_status(). This
patch is in preparation to adding support for fetching PTM_STATUS
types. No functional changes.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This makes it a lot clearer that we're expecting a recipient as the
argument. A follow-up patch will use the argument 'type' as the status
type selector (standard or ptm).
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds a new helper function to perform a sanity check of the
given URB to see whether it contains a valid endpoint. It's a light-
weight version of what usb_submit_urb() does, but without the kernel
warning followed by the stack trace, just returns an error code.
Especially for a driver that doesn't parse the descriptor but fills
the URB with the fixed endpoint (e.g. some quirks for non-compliant
devices), this kind of check is preferable at the probe phase before
actually submitting the urb.
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Since when we got rid of usbfs, the /proc/bus/usb is now
elsewhere. Fix references for it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several drivers have implemented their endpoint look-up loops in such a
way that they have picked the last endpoint descriptor of the specified
type should more than one such descriptor exist.
To avoid any regressions, add corresponding helpers to lookup endpoints
by searching the endpoint descriptors in reverse order.
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>