There are unfortunately a number of situations where vap->iv_bss is changed
or freed by some code in net80211. Because multiple threads can concurrently
be doing work (and the vap->iv_bss access isn't at all done behind any kind
of lock), it's quite possible that:
* a change will occur in one thread - eg, by a call through
ieee80211_sta_join1();
* a state change occurs in another thread - eg an RX is scheduled
in the ath tasklet and it calls ieee80211_input_mimo_all(), which
does dereference vap->iv_bss;
* these two executing concurrently, causing things to explode.
Another instance is ath_beacon_alloc() which takes an ieee80211_node *.
It's called with the vap->iv_bss node from ath_newstate(). If the node has
changed in the meantime (say it's been freed elsewhere) the reference
that it grabbed _before_ refcounting it may be stale.
I would _prefer_ that these sorts of things were serialised somewhere but
that may be a bit much to ask. Instead, the best we can (currently) hope
is that the underlying bss node is still (somewhat) valid.
There is a related PR (kern/164382) described by the first case above.
That should be fixed by properly serialising the RX path and reset path
so an RX can't occur at the same time as the vap free/shutdown path.
This is inspired by some related fixes in r212127.
PR: kern/165060
starting up before the previous script finishes. This prevents an
infinite number of them from piling up and slowing a system down.
Since all the refactoring to make this happen required churning the
indenting of most of this file, make the indentation more consistent.
Reviewed by: simon
MFC after: 1 week
The reasoning behind this, is that if we are consistent in our
documentation about the uint*_t stuff, people will be less tempted to
write new code that uses the non-standard types.
I am not going to bump the man page dates, as these changes can be
considered style nits. The meaning of the man pages is unaffected.
MFC after: 1 month
The main benefit is that watchdogd would shutdown after most of other
daemons/servers and thus, for example, would remedy a system hang caused
by unlucky X server shutdown.
Reviewed by: dougb (earlier version)
MFC after: 2 weeks
According to POSIX, -a is equal to -bdlprtTu. It seems this is not true
in practice, as -b normally restricts the output to BOOT_TIME entries
and all implementations that I know of don't.
This has the following advantages:
- During boot, the BOOT_TIME record is now written right after the file
systems become writable, but before users are allowed to log in. This
means that they can't cause `hidden logins' by logging in right before
init(8) kicks in.
- The pututxline(3) function may potentially block on file locking,
though this is very rare to occur. By placing it in an rc script, the
user can still kill it with ^C if needed.
- Most importantly: jails don't use init(8). This means that a force
reboot of a system running jails will leave stale entries in the
accounting database of the jails individually.
Ignore the NAT_T extension types so we can at least dump the SADB from
the in-base libipsec/setkey without error when NAT_T support is present
in the kernel, though not printing the additional information yet.
However in case there is no NAT_T support in kernel still consider them
to be an error.
MFC after: 8 weeks
At first, I added a utility called utxrm(8) to remove stale entries from
the user accounting database. It seems there are cases in which we need
to perform different operations on the database as well. Simply rename
utxrm(8) to utx(8) and place the old code under the "rm" command.
In addition to "rm", this tool supports "boot" and "shutdown", which are
going to be used by an rc-script which I am going to commit separately.
for a shared mapping and marking the entry for inheritance.
Other thread might execute vmspace_fork() in between (e.g. by fork(2)),
resulting in the mapping becoming private.
Noted and reviewed by: alc
MFC after: 1 week
be the same chip):
- The I/O port resource may not be available with these. However, given
that we actually only need this resource for some controllers that
require their firmware to be up- and downloaded (which excludes the
SAS1078{,DE}) just handle failure to allocate this resource gracefully
when possible. While at it, generally put non-fatal resource allocation
failures under bootverbose.
- SAS1078{,DE} use a different hard reset protocol.
- Add workarounds for the 36GB physical address limitation of scatter/
gather elements of these controllers.
Tested by: Slawa Olhovchenkov
PR: 149220 (remaining part)
If the utmpx database gets updated while an application is reading it,
there is a chance the reading application processes partially
overwritten entries. To solve this, make sure we always read a multiple
of sizeof(struct futx) at a time.
MFC after: 2 weeks
of rcorder. Somehow in the intervening period addswap got moved to the
very end, which is almost certainly not what we want.
This change moves it to right after kld so that for users who need it,
they'll get it ASAP.
conditional code parts not used by or applicable to FreeBSD.
The new implementation is supposed to be able to cope with changes to
the 'l' versions of the msghdr structs now used as well as to if_data
allowing future changes without breaking things.
This restores carp(4) config support in HEAD after r231504.
Reviewed by: glebius, brooks
MFC After: 3 months
on extended and extensible structs if_msghdrl and ifa_msghdrl. This
will allow us to extend both the msghdrl structs and eventually if_data
in the future without breaking the ABI.
Bump __FreeBSD_version to allow ports to more easily detect the new API.
Reviewed by: glebius, brooks
MFC after: 3 days
both 64bit and 32bit binaries, not for 64bit only.
The set of the flag is not neccessary there, because the only current
user of the cpu_set_user_tls() is create_thread(), which calls
cpu_set_upcall() before and cpu_set_upcall() itself sets PCB_FULL_IRET.
Change the function for consistency and preserve existing KPI for now.
MFC after: 1 week
