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
function. Many existing clients don't understand POLLNVAL and instead
relies on an error code from the read(), write() or ioctl() system
call. Also make sure we wakeup any client pollers before the cuse
server is closing, so they don't wait forever for an event.
Before this change, the current code handles SIOCGIFADDR the same
way with SIOCSIFADDR, which involves full arp_ifinit, et al. They
should be unnecessary for SIOCGIFADDR case.
Differential Revision: https://reviews.freebsd.org/D1508
Reviewed by: glebius
MFC after: 2 weeks
Instead of reusing the same reg parsing code, create one, common function
that puts reg contents to the resource list. Address cells and size cells
are passed rather than acquired here so that any bus can have different
default values.
Obtained from: Semihalf
Reviewed by: andrew, ian, nwhitehorn
Sponsored by: The FreeBSD Foundation
driver name and NIC driver softc via the device(9) tree,
instead of going dirty through the ifnet(9) layer.
Differential Revision: D1506
Reviewed by: imp, jhb
if_ixl to version 1.3.0, if_ixlv to version 1.2.0
- Major change in both drivers is to add RSS support
- In ixl fix some interface speed related issues, dual
speed was not changing correctly, KR/X media was not
displaying correctly (this has a workaround until a
more robust media handling is in place)
- Add a warning when using Dell NPAR and the speed is
less than 10G
- Wrap a queue hung message in IXL_DEBUG, as it is non-fatal,
and without tuning can display excessively
MFC after: 1 week
Only i386 and amd64 provide a non-trivial __getcontextx(). Use a common
trivial implementation in gen/ for other architectures, rather than
copying the file to each MD subdirectory.
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1472
use ifqueue at all. Second, there is no point in this lockless check.
Either positive or negative result of the check could be incorrect after
a tick.
Reviewed by: tuexen
Sponsored by: Nginx, Inc.
use ifqueue at all. Second, there is no point in this lockless check.
Either positive or negative result of the check could be incorrect after
a tick.
Sponsored by: Nginx, Inc.
legitimacy of removal is proved by the fact that implementation contained
a critical bug: the response allocated was sizeof(pointer), while should
had been 2*sizeof(struct ng_cisco_ipaddr). The reason for ng_iface(4) to
support ng_cisco(4) message isn't explained anywhere, and code comes from
original Whistle import.
Sponsored by: Nginx, Inc.
a) assumed that ifqueue length is measured in bytes, instead of packets
b) assumed that any interface has working ifqueue
c) incremented global counter instead of ifi_oqdrops
Sponsored by: Nginx, Inc.
DCTCP congestion control algorithm aims to maximise throughput and minimise
latency in data center networks by utilising the proportion of Explicit
Congestion Notification (ECN) marked packets received from capable hardware as a
congestion signal.
Highlights:
Implemented as a mod_cc(4) module.
ECN (Explicit congestion notification) processing is done differently from
RFC3168.
Takes one-sided DCTCP into consideration where only one of the sides is using
DCTCP and other is using standard ECN.
IETF draft: http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00
Thesis report by Midori Kato: https://eggert.org/students/kato-thesis.pdf
Submitted by: Midori Kato <katoon@sfc.wide.ad.jp> and
Lars Eggert <lars@netapp.com>
with help and modifications from
hiren
Differential Revision: https://reviews.freebsd.org/D604
Reviewed by: gnn
For /dev/mem, when requested physical address is not accessible by the
direct map, do temporal remaping with the caching attribute
'uncached'. Limit the accessible addresses by MAXPHYADDR, since the
architecture disallowes writing non-zero into reserved bits of ptes
(or setting garbage into NX).
For /dev/kmem, only access existing kernel mappings for direct map
region. For all other addresses, obtain a physical address of the
mapping and fall back to the /dev/mem mechanism. This ensures that
/dev/kmem i/o does not fault even if the accessed region is changed in
parallel, by using either direct map or temporal mapping.
For both devices, operate on one page by iteration. Do not return
error if any bytes were moved around, return the (partial) bytes count
to userspace.
Reviewed by: alc
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
unnecessary filter configuration code in nge_init_locked().
While I'm here add a check for driver running state for multicast
filter handling. Also remove unnecessary assignment to error
variable since it is cleared in the function entry.
Suggested by: brad@OpenBSD.org
Features by CPUID as CPUID.80000008H:EAX[7:0], into variable cpu_maxphyaddr.
Reviewed by: alc
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
