When detaching device trees parent devices must be detached prior to
detaching its children. This is because parent devices can have
pointers to the child devices in their softcs which are not
invalidated by device_delete_child(). This can cause use after free
issues and panic().
Device drivers implementing trees, must ensure its detach function
detaches or deletes all its children before returning.
While at it remove now redundant device_detach() calls before
device_delete_child() and device_delete_children(), mostly in
the USB controller drivers.
Tested by: Jan Henrik Sylvester <me@janh.de>
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D8070
MFC after: 2 weeks
mutexes or using any callouts when active.
Trying to lock a mutex when KDB is active or the scheduler is stopped
can result in infinite wait loops. The same goes for calling callout
related functions which in turn lock mutexes.
If the USB controller at which a USB keyboard is connected is idle
when KDB is entered, polling the USB keyboard via USB will always
succeed. Else polling may fail depending on which state the USB
subsystem and USB interrupt handler is in. This is unavoidable unless
KDB can wait for USB interrupt threads to complete before stalling the
CPU(s).
Tested by: Bruce Evans <bde@freebsd.org>
MFC after: 4 weeks
by reviving the SX control request lock and refining which lock
protects the common scratch area in "struct usb_device".
The SX control request lock was removed by r246759 because it caused a
lock order reversal with the USB enumeration lock inside
usbd_transfer_setup() as a function of r246616. It was thought that
reducing the number of locks would resolve the LOR, but because some
USB device drivers use usbd_do_request_flags() inside callback
functions, like in taskqueues, a deadlock may occur when these are
drained from device_detach(). By restoring the SX control request
lock usbd_do_request_flags() is allowed to complete its execution
when a USB device driver is detaching. By using the SX control request
lock to protect the scratch area, the LOR introduced by r246616 is
also resolved.
Bump the FreeBSD version while at it to force recompilation of all USB
kernel modules.
Found by: avos@
MFC after: 1 week
- Move all files related to the LinuxKPI into sys/compat/linuxkpi and
its subfolders.
- Update sys/conf/files and some Makefiles to use new file locations.
- Added description of COMPAT_LINUXKPI to sys/conf/NOTES which in turn
adds the LinuxKPI to all LINT builds.
- The LinuxKPI can be added to the kernel by setting the
COMPAT_LINUXKPI option. The OFED kernel option no longer builds the
LinuxKPI into the kernel. This was done to keep the build rules for
the LinuxKPI in sys/conf/files simple.
- Extend the LinuxKPI module to include support for USB by moving the
Linux USB compat from usb.ko to linuxkpi.ko.
- Bump the FreeBSD_version.
- A universe kernel build has been done.
Reviewed by: np @ (cxgb and cxgbe related changes only)
Sponsored by: Mellanox Technologies
like RPI-B and RPI-2.
Description of problem:
USB transfers can process data in their callbacks sometimes causing
unacceptable latency for other USB transfers. Separate BULK completion
callbacks from CONTROL, INTERRUPT and ISOCHRONOUS callbacks, and give
BULK completion callbacks lesser execution priority than the
others. This way USB audio won't be interfered by heavy USB ethernet
usage for example.
Further serve USB transfer completion in a round robin fashion,
instead of only serving the most CPU hungry. This has been done by
adding a third flag to USB transfer queue structure which keeps track
of looping callbacks. The "command" callback function then decides
what to do when looping.
MFC after: 2 weeks
simultaneously detaching kernel drivers on the same USB device we can
get stuck in the "usb_wait_pending_ref_locked()" function because the
conditions needed for allowing detach are not met. The "destroy_dev()"
function waits for all system calls involving the given character
device to return. Character device system calls may lock the USB
enumeration lock, which is also held when "destroy_dev()" is
called. This can sometimes lead to a deadlock not noticed by
WITNESS. The current solution is to ensure the calling thread is the
only one holding the USB enumeration lock and prevent other threads
from getting refs while a USB device detach is ongoing. This turned
out not to be sufficient. To solve this deadlock we could use
"destroy_dev_sched()" to schedule the device destruction in the
background, but then we don't know when it is safe to free() the
private data of the character device. Instead a callback function is
executed by the USB explore process to kill off any leftover USB
character devices synchronously after the USB device explore code is
finished and the USB enumeration lock is no longer locked. This makes
porting easier and also ensures us that character devices must
eventually go away after a USB device detach.
While at it ensure that "flag_iserror" is only written when "priv_mtx"
is locked, which is protecting it.
MFC after: 5 days
These changes prevent sysctl(8) from returning proper output,
such as:
1) no output from sysctl(8)
2) erroneously returning ENOMEM with tools like truss(1)
or uname(1)
truss: can not get etype: Cannot allocate memory
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.
Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
shutdown by putting the former under !rebooting and turning the latter into
debug messages.
Reviewed by: hps
MFC after: 1 week
Sponsored by: Bally Wulff Games & Entertainment GmbH
create character devices. The deadlock can happen if an application is
issuing IOCTLs which require USB refcounting, at the same time the USB
device is detaching.
There is already a counter in place in the USB device structure to
detect this situation, but it was not always checked ahead of invoking
functions that might destroy character devices, like detach, set
configuration, set alternate interface or detach active kernel driver.
Reported by: Daniel O'Connor <doconnor@gsoft.com.au>
MFC after: 1 week
with USB device detach when using character device handles. This also
includes LibUSB. It turns out that "usb_close()" cannot always get a
reference to clean up its USB transfers and such, if called during the
kernel USB device detach.
Analysis by: hselasky @
Reported by: Juergen Lock <nox@jelal.kn-bremen.de>
MFC after: 1 week
found in High Speed USB HUBs which translate from High Speed USB into
FULL or LOW speed USB. In some rare cases SPLIT transactions might get
lost, which might leave the TT in an unknown state. Whenever we detect
such an error try to issue either a clear TT buffer request, or if
that is not possible reset the whole TT.
MFC after: 1 week
in reduced memory systems.
- Split allocation and freeing of the configuration descriptor into a separate
function, so that the configuration descriptor can be made fixed size
to save memory allocations. This applies for both device and host mode.
Else they won't enumerate at all:
hw.usb.full_ddesc=1
- Reduce the USB descriptor read timeout from 1000ms to
500ms. Typical value for LOW speed devices is 50-100ms.
- Enumerate USB device a maximum of 3 times when a port
connection change event is detected, before giving up.
MFC after: 1 month
enumeration lock. Make sure all callers of usbd_enum_lock() check the return
value. Remove the control transfer specific lock. Bump the FreeBSD version
number, hence external USB modules may need to be recompiled due to a USB
device structure change.
MFC after: 1 week
so that simultaneous access cannot happen. Protect scratch area using
the enumeration lock. Also reduce stack usage in usbd_transfer_setup()
by moving some big stack members to the scratch area. This saves around
200 bytes of stack.
- Fix a whitespace.
MFC after: 1 week
into the FreeBSD boot loader, typically for non-USB aware BIOSes, EFI systems
or embedded platforms. This is also useful for out of the system compilation
of the FreeBSD USB stack for various purposes. The USB kernel files can
now optionally include a global header file which should include all needed
definitions required to compile the FreeBSD USB stack. When the global USB
header file is included, no other USB header files will be included by
default.
Add new file containing the USB stack configuration for the
FreeBSD loader build.
Replace some __FBSDID()'s by /* $FreeBSD$ */ comments. Now all
USB files follow the same style.
Use cases:
- console in loader via USB
- loading kernel via USB
Discussed with: Hiroki Sato, hrs @ EuroBSDCon
in SUPER-speed mode, USB 3.0.
This feature has not been tested yet, due to lack of hardware.
This feature is useful when implementing protocols like UASP,
USB attached SCSI which promises higher USB mass storage throughput.
This patch also implements support for hardware processing of endpoints
for increased performance. The switching to hardware processing
of an endpoint is done via a callback to the USB controller driver. The
stream feature is implemented like a variant of a hardware USB protocol.
USB controller drivers implementing device mode needs to be updated to
implement the new "xfer_stall" USB controller method and remove the
"xfer" argument from the "set_stall" method.
The API's toward existing USB drivers are preserved. To setup a USB transfer
in stream mode, set the "stream_id" field of the USB config structure to
the desired value.
The maximum number of BULK streams is currently hardcoded and limited to 8
via a define in usb_freebsd.h.
All USB drivers should be re-compiled after this change.
LibUSB will be updated next week to support streams mode. A new IOCTL to
setup BULK streams as already been implemented. The ugen device nodes
currently only supports stream ID zero.
The FreeBSD version has been bumped.
MFC after: 2 weeks
which does not support the no synchronize cache SCSI command.
The __FreeBSD_version version macro has been bumped and
external kernel modules needs to be recompiled after
this patch.
Approved by: re (kib)
MFC after: 1 week
PR: usb/160299
device having the same name like a previous one is not created before the old
one is gone. This fixes some panics due to asserts in the devfs code which
were added recently.
Approved by: re (kib)
MFC after: 1 week
dynamically loaded device drivers get a chance to run their event hooks.
- Decouple the USB suspend and resume lock from witness. It produces some
false warnings due to reusing the lock name among multiple devices.
MFC after: 3 days
This brings USB bus more in line with how newbus is supposed to be used.
Also, because of the two-pass probing the following message was produced
by devd in default configuration when almost any USB device was
connected:
Unknown USB device: vendor <> product <> bus <>
This should be fixed now.
Note that many USB device drivers pass some information from probe
method to attach method via ivars. For this to continue working we rely
on the fact that the subr_bus code calls probe method of a winning driver
again before calling its attach method in the case where multiple
drivers claim to support a device. This is done because device
description is set in successful probe methods and we want to get a correct
device description from a winning driver. So now this logic is re-used
for setting ivars too.
Reviewed by: hselasky
MFC after: 1 month
hence existing applications like webcamd are expecting that.
This problem was introduced by SVN change 214221 where cdev=
was replaced by ugen= by accident. Solve this problem by
redefining cdev= in devd notifications.
MFC after 3 days.
Approved by: thompsa (mentor)
