src-test2/sys/dev/usb/usb_dev.c, branch release/11.0.0

Check for signals when locking the USB enumeration thread from

2016-05-25T07:48:36Z

userspace, so that USB applications can be killed if an enumeration thread should be stuck for various reasons. MFC after: 1 week

dev/usb: minor spelling fixes in comments.

2016-05-02T17:44:03Z

No functional change. Reviewed by: hselasky

Don't wait forever for USB data to be flushed.

2015-06-05T06:06:07Z

MFC after: 1 week

Resolve a special case deadlock: When two or more threads are

2015-01-13T16:37:43Z

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

When we fail to get a USB reference we should just return, because

2014-10-03T16:09:46Z

there are no more references held. MFC after: 3 days

Pull in r267961 and r267973 again. Fix for issues reported will follow.

2014-06-28T03:56:17Z

Revert r267961, r267973:

2014-06-27T22:05:21Z

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

Extend the meaning of the CTLFLAG_TUN flag to automatically check if

2014-06-27T16:33:43Z

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

Resolve a deadlock setting the USB configuration index from userspace

2014-06-08T20:10:29Z

on USB HUBs by moving the code into the USB explore threads. The deadlock happens because child devices of the USB HUB don't have the expected reference count when called from outside the explore thread. Only the HUB device itself, which the IOCTL interface locks, gets the correct reference count. MFC after: 3 days

Try to resolve a possible deadlock when detaching USB devices which

2014-03-20T13:53:24Z

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 MFC after: 1 week