due to the vm object being locked.
When a process writes large amounts of data to a file, the vm object associated
with that file can contain most of the physical pages on the machine. If the
process is preempted while holding the lock on the vm object, pagedaemon would
be able to move very few pages from PQ_INACTIVE to PQ_CACHE or from PQ_ACTIVE
to PQ_INACTIVE, resulting in unlimited cleaning of dirty pages belonging to
other vm objects.
Temporarily unlock the page queues lock while locking vm objects to avoid lock
order violation. Detect and handle relevant page queue changes.
This change depends on both the lock portion of struct vm_object and normal
struct vm_page being type stable.
Reviewed by: alc
to atomically return either an existing set of IP multicast options for the
PCB, or a newlly allocated set with default values. The inpcb is returned
locked. This function may sleep.
Call ip_moptions() to acquire a reference to a PCB's socket options, and
perform the update of the options while holding the PCB lock. Release the
lock before returning.
Remove garbage collection of multicast options when values return to the
default, as this complicates locking substantially. Most applications
allocate a socket either to be multicast, or not, and don't tend to keep
around sockets that have previously been used for multicast, then used for
unicast.
This closes a number of race conditions involving multiple threads or
processes modifying the IP multicast state of a socket simultaenously.
MFC after: 7 days
list lock, as there has been a report that an alternative lock order
is getting introduced. This should help ferret it out.
Reported by: Ed Maste <emaste at phaedrus dot sandvine dot ca>
device driver, owned by the network stack, or initialized by the device
driver before attach and read-only from then on.
Not all device drivers and network stack components currently follow
these rules, especially with respect to IFF_UP, and a few exceptions
with IFF_ALLMULTI.
MFC after: 7 days
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.
Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.
Reviewed by: pjd, bz
MFC after: 7 days
and move both flags from ifnet.if_flags to ifnet.if_drv_flags, making
and documenting the locking of these flags the responsibility of the
device driver, not the network stack. The flags for these two fields
will be mutually exclusive so that they can be exposed to user space as
though they were stored in the same variable.
Provide #defines to provide the old names #ifndef _KERNEL, so that user
applications (such as ifconfig) can use the old flag names. Using the
old names in a device driver will result in a compile error in order to
help device driver writers adopt the new model.
When exposing the interface flags to user space, via interface ioctls
or routing sockets, or the two fields together. Since the driver flags
cannot currently be set for user space, no new logic is currently
required to handle this case.
Add some assertions that general purpose network stack routines, such
as if_setflags(), are not improperly used on driver-owned flags.
With this change, a large number of very minor network stack races are
closed, subject to correct device driver locking. Most were likely
never triggered.
Driver sweep to follow; many thanks to pjd and bz for the line-by-line
review they gave this patch.
Reviewed by: pjd, bz
MFC after: 7 days
- Push 'i' into the only block where it is used.
- Remove redundant check for rt being NULL. If rt_check() hasn't
returned an error, then rt is valid.
Reviewed by: gnn
from the port number (if any exists). This unbreaks
env HTTP_PROXY="http://localhost:3128/" portsnap fetch
While I'm here, list both the host and the port in the error message
output if getaddrinfo() fails, since either of them could be responsible
for the failure.
than what we already have" message. [1]
When operating with the undocumented --debug option, replace "xargs
phttpget" with "xargs -t phttpget", since that might conceivably help
debugging.
Noticed by: simon [1]
m_copym(m, 0, M_COPYALL, how).
This is required for strict alignment architectures where we align the IP
header in the input path but m_copym() will create an unaligned copy in
bridge_broadcast(). m_copypacket() preserves alignment of the first mbuf.
Noticed by: Petri Simolin
Approved by: mlaier (mentor)
MFC after: 3 days
not holding any non-sleep-able-locks locks when copyin is called.
This gets executed un-conditionally since we have no function
to wire the buffer in this direction.
Pointed out by: truckman
MFC after: 1 week
the timeout routine.
- Fix locking in detach.
- Add locking in shutdown.
- Don't mess with the PCI command register in resume, the PCI bus driver
already does this for us.
- Add locking to the non-serial ifmedia routines.
- Fix locking in ioctl.
- Remove spls and support for 4.x.
MFC after: 1 week
fast, lightweight, and generally good way for users to keep their
ports trees up to date.
This is version 0.9.4 from the ports tree (sysutils/portsnap) with
the following changes:
1. The experimental pipelined http code is enabled. No seatbelts
in -CURRENT. (^_^)
2. The working directory has moved from /usr/local/portsnap to
/var/db/portsnap (as discussed on -arch two days ago).
3. Portsnap now fetches a list of mirrors (distributed as DNS SRV
records) and selects one randomly. This should help to avoid the
uneven loading which plagues the cvsup mirror network.
4. The license is now 2-clause BSD instead of 3-clause BSD.
5. Various incidental changes to make portsnap fit into the base
system's build mechanics.
X-MFC-After: 6.0-RELEASE
X-MFC-Before: 5.5-RELEASE
X-MFC-To: RELENG_6, RELENG_5, ports
discussed on: -arch and several other places
"yes please" from: simon, remko, flz, Diane Bruce
thinks this is a great idea: bsdimp
Hopes he didn't forget any files: cperciva
event handler, dev_clone, which accepts a credential argument.
Implementors of the event can ignore it if they're not interested,
and most do. This avoids having multiple event handler types and
fall-back/precedence logic in devfs.
This changes the kernel API for /dev cloning, and may affect third
party packages containg cloning kernel modules.
Requested by: phk
MFC after: 3 days
I copied strcasecmp() from userland to the kernel and it didn't worked!
I started to debug the problem and I find out that this line:
while (tolower(*us1) == tolower(*us2++)) {
was adding _3_ bytes to 'us2' pointer. Am I loosing my minds here?!...
No, in-kernel tolower() is a macro which uses its argument three times.
Bad tolower(9), no cookie.
the buffer has not been wired and we are holding any non-sleep-able locks,
drop a witness warning. If the buffer has not been wired, it is possible
that the writing of the data can sleep, especially if the page is not in
memory. This can result in a number of different locking issues, including
dead locks.
MFC after: 1 week
Discussed with: rwatson
Reviewed by: jhb
