has been set. Assert that this is the case so that we catch filesystems
who are using naked VOP_LOCKs in illegal cases.
Sponsored by: Isilon Systems, Inc.
considered to be as good as an exclusive lock, although there is still a
possibility of someone acquiring a VOP LOCK while xlock is held.
Sponsored by: Isilon Systems, Inc.
List devfs_dirents rather than vnodes off their shared struct cdev, this
saves a pointer field in the vnode at the expense of a field in the
devfs_dirent. There are often 100 times more vnodes so this is bargain.
In addition it makes it harder for people to try to do stypid things like
"finding the vnode from cdev".
Since DEVFS handles all VCHR nodes now, we can do the vnode related
cleanup in devfs_reclaim() instead of in dev_rel() and vgonel().
Similarly, we can do the struct cdev related cleanup in dev_rel()
instead of devfs_reclaim().
rename idestroy_dev() to destroy_devl() for consistency.
Add LIST_ENTRY de_alias to struct devfs_dirent.
Remove v_specnext from struct vnode.
Change si_hlist to si_alist in struct cdev.
String new devfs vnodes' devfs_dirent on si_alist when
we create them and take them off in devfs_reclaim().
Fix devfs_revoke() accordingly. Also don't clear fields
devfs_reclaim() will clear when called from vgone();
Let devfs_reclaim() call dev_rel() instead of vgonel().
Move the usecount tracking from dev_rel() to devfs_reclaim(),
and let dev_rel() take a struct cdev argument instead of vnode.
Destroy SI_CHEAPCLONE devices in dev_rel() (instead of
devfs_reclaim()) when they are no longer used. (This
should maybe happen in devfs_close() instead.)
a socket from a regular socket to a listening socket able to accept new
connections. As part of this state transition, solisten() calls into the
protocol to update protocol-layer state. There were several bugs in this
implementation that could result in a race wherein a TCP SYN received
in the interval between the protocol state transition and the shortly
following socket layer transition would result in a panic in the TCP code,
as the socket would be in the TCPS_LISTEN state, but the socket would not
have the SO_ACCEPTCONN flag set.
This change does the following:
- Pushes the socket state transition from the socket layer solisten() to
to socket "library" routines called from the protocol. This permits
the socket routines to be called while holding the protocol mutexes,
preventing a race exposing the incomplete socket state transition to TCP
after the TCP state transition has completed. The check for a socket
layer state transition is performed by solisten_proto_check(), and the
actual transition is performed by solisten_proto().
- Holds the socket lock for the duration of the socket state test and set,
and over the protocol layer state transition, which is now possible as
the socket lock is acquired by the protocol layer, rather than vice
versa. This prevents additional state related races in the socket
layer.
This permits the dual transition of socket layer and protocol layer state
to occur while holding locks for both layers, making the two changes
atomic with respect to one another. Similar changes are likely require
elsewhere in the socket/protocol code.
Reported by: Peter Holm <peter@holm.cc>
Review and fixes from: emax, Antoine Brodin <antoine.brodin@laposte.net>
Philosophical head nod: gnn
only call the protocol's pru_rcvd() if the protocol has the flag
PR_WANTRCVD set. This brings that instance of pru_rcvd() into line with
the rest, which do check the flag.
MFC after: 3 days
of the global UNIX domain socket mutex: no protection is needed that
early in the setup of the UNIX domain socket and socket structures.
MFC after: 3 days
patch from kan@).
Pull bufobj_invalbuf() out of vinvalbuf() and make g_vfs call it on
close. This is not yet a generally safe function, but for this very
specific use it is safe. This solves the problem with buffers not
being flushed by unmount or after failed mount attempts.
so->so_options when solisten() will succeed, rather than setting it
conditionally based on there not being queued sockets in the completed
socket queue. Otherwise, if the protocol exposes new sockets via the
completed queue before solisten() completes, the listen() system call
will succeed, but the socket and protocol state will be out of sync.
For TCP, this didn't happen in practice, as the TCP code will panic if
a new connection comes in after the tcpcb has been transitioned to a
listening state but the socket doesn't have SO_ACCEPTCONN set.
This is historical behavior resulting from bitrot since 4.3BSD, in which
that line of code was associated with the conditional NULL'ing of the
connection queue pointers (one-time initialization to be performed
during the transition to a listening socket), which are now initialized
separately.
Discussed with: fenner, gnn
MFC after: 3 days
driver. This used to be handled by cpufreq_drv_settings() but it's
useful to get the type/flags separately from getting the settings.
(For example, you don't have to pass an array of cf_setting just to find
the driver type.)
Use this new method in our in-tree drivers to detect reliably if acpi_perf
is present and owns the hardware. This simplifies logic in drivers as well
as fixing a bug introduced in my last commit where too many drivers attached.
soref() to also covering the update of so_state. While no other user
threads can update the socket state here as it's not yet hooked up to
the file descriptor array yet, the protocol could also frob the
socket state here, leading to a lost update to the so_state field.
No reported instances of this bug (as yet).
MFC after: 3 days
connection status before inserting the new socket into the listen
socket's accept queue, or there might be a race in which another thread
wakes up when the accept lock is released, and sees the socket before its
state is set correctly. The wakeup still occurs after the accept lock is
released. There have been no diagnoses of this bug in real-world systems
(as yet).
MFC after: 3 days
statement from some files, so re-add it for the moment, until the
related legalese is sorted out. This change affects:
sys/kern/kern_mbuf.c
sys/vm/memguard.c
sys/vm/memguard.h
sys/vm/uma.h
sys/vm/uma_core.c
sys/vm/uma_dbg.c
sys/vm/uma_dbg.h
sys/vm/uma_int.h
the rate for the 100% state once. Afterwards, use that value for deriving
states. This should fix the problem where the calibrated frequency was
different once a switch was done, giving a different set of levels each
time. Also, properly search for the right cpufreqX device when detaching.
override the current freq level temporarily and restore it when the
higher priority condition is past. Note that only the first overridden
value is saved. Callers pass NULL to CPUFREQ_SET to restore the saved
level. Priorities are not yet used so this commit should have no effect.
are not added to the list(s) of available settings. However, other drivers
can call the CPUFREQ_DRV_SETTINGS() method on those devices directly to
get info about available settings.
Update the acpi_perf(4) driver to use this flag in the presence of
"functional fixed hardware." Thus, future drivers like Powernow can
query acpi_perf for platform info but perform frequency transitions
themselves.
on dev.cpu.0 will affect all of the CPUs together. In the future,
independent control will be supported but this is good enough for now.
Check that the timecounter isn't TSC before switching (from Colin Percival.)
former is callable from user space and the latter from the kernel one. Make
kernel version take additional argument which tells if the respective call
should check for additional restrictions for sending signals to suid/sugid
applications or not.
Make all emulation layers using non-checked version, since signal numbers in
emulation layers can have different meaning that in native mode and such
protection can cause misbehaviour.
As a result remove LIBTHR from the signals allowed to be delivered to a
suid/sugid application.
Requested (sorta) by: rwatson
MFC after: 2 weeks
This information will be very useful for people who are tuning applications
which have a dependence on IPC mechanisms.
The following OIDs were documented:
Message queues:
kern.ipc.msgmax
kern.ipc.msgmni
kern.ipc.msgmnb
kern.ipc.msgtlq
kern.ipc.msgssz
kern.ipc.msgseg
Semaphores:
kern.ipc.semmap
kern.ipc.semmni
kern.ipc.semmns
kern.ipc.semmnu
kern.ipc.semmsl
kern.ipc.semopm
kern.ipc.semume
kern.ipc.semusz
kern.ipc.semvmx
kern.ipc.semaem
Shared memory:
kern.ipc.shmmax
kern.ipc.shmmin
kern.ipc.shmmni
kern.ipc.shmseg
kern.ipc.shmall
kern.ipc.shm_use_phys
kern.ipc.shm_allow_removed
kern.ipc.shmsegs
These new descriptions can be viewed using sysctl -d
PR: kern/65219
Submitted by: Dan Nelson <dnelson at allantgroup dot com> (modified)
No objections: developers@
Descriptions reviewed by: gnn
MFC after: 1 week
suid application. The problem is that Linux applications using old Linux
threads (pre-NPTL) use signal 32 (linux SIGRTMIN) for communication between
thread-processes. If such an linux application is installed suid or sgid
and security.bsd.conservative_signals=1 (default), then permission will be
denied to send such a signal and the application will freeze.
I believe the same will be true for native applications that use libthr,
since libthr uses SIGTHR for implementing conditional variables.
PR: 72922
Submitted by: Andriy Gapon <avg@icyb.net.ua>
MFC after: 2 weeks
list, set `curr_callout' to NULL. This ensures that we won't attempt
to cancel the current callout if the original callout structure
gets recycled while we wait to acquire Giant.
This is reported to fix an intermittent syscons problem that was
introduced by revision 1.96.
do not need to perform an extra memory fetch in the Packet (Mbuf+Cluster)
constructor to initialize the reference counter anymore. The reference
counts are located in a separate memory region (in the slab header,
because this zone is UMA_ZONE_REFCNT), so the memory fetch resulted very
often in a cache miss. Additionally, and perhaps more significantly,
optimize the free mbuf+cluster (packet) case, which is very common, to
no longer require an atomic operation on free (to verify the reference
counter) if the reference on the cluster has never been increased (also
very common). Reduces an atomic on mbuf free on average.
Original patch submitted by: Gerrit Nagelhout <gnagelhout@sandvine.com>
