- If there aren't spinlocks held, but there are problems with old
sleeplocks, they are not reported.
- If the spinlock found is not the only one, problems are not reported.
Fix these 2 problems.
Reported by: tegge
and ffs_lock. This cannot catch situations where holdcnt is incremented
not by curthread, but I think it is useful.
Reviewed by: tegge, attilio
Tested by: pho
MFC after: 2 weeks
MNTK_UNMOUNT before, and mnt_mtx is used as interlock. vfs_busy() always
tries to obtain a shared lock on mnt_lock, the other user is unmount who
tries to drain it, setting MNTK_UNMOUNT before.
Reviewed by: tegge, attilio
Tested by: pho
MFC after: 2 weeks
realtimer_expire() to not rearm the timer, otherwise there is a chance
that a callout will be left there and be tiggered in future unexpectly.
Bug reported by: tegge@
not the string formatted at the time of CTRX() call. Stack_ktr(9) uses
an on-stack buffer for the symbol name, that is supplied as an argument
to ktr. As result, stack_ktr() traces show garbage or cause page faults.
Fix stack_ktr() by using pointer to module symbol table that is supposed
to have a longer lifetime.
Tested by: pho
MFC after: 1 week
credentials from inp_cred which is also available after the
socket is gone.
Switch cr_canseesocket consumers to cr_canseeinpcb.
This removes an extra acquisition of the socket lock.
Reviewed by: rwatson
MFC after: 3 months (set timer; decide then)
PCPU_PTR() curthread can migrate on another CPU and get incorrect
results.
- Fix a similar race into witness_warn().
- Fix the interlock's checks bypassing by correctly using the appropriate
children even when the lock_list chunk to be explored is not the first
one.
- Allow witness_warn() to work with spinlocks too.
Bugs found by: tegge
Submitted by: jhb, tegge
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
- Change the ddb(4) commands to be more useful (by thompsa@):
- `show ttys' is now called `show all ttys'. This command will now
also display the address where the TTY data structure resides.
- Add `show tty <addr>', which dumps the TTY in a readable form.
- Place an upper bound on the TTY buffer sizes. Some drivers do not want
to care about baud rates. Protect these drivers by preventing the TTY
buffers from getting enormous. Right now we'll just clamp it to 64K,
which is pretty high, taking into account that these buffers are only
used by the built-in discipline.
- Only call ttydev_leave() when needed. Back in April/May the TTY
reference counting mechanism was a little different, which required us
to call ttydev_leave() each time we finished a cdev operation.
Nowadays we only need to call ttydev_leave() when we really mark it as
being closed.
- Improve return codes of read() and write() on TTY device nodes.
- Make sure we really wake up all blocked threads when the driver calls
tty_rel_gone(). There were some possible code paths where we didn't
properly wake up any readers/writers.
- Add extra assertions to prevent sleeping on a TTY that has been
abandoned by the driver.
- Use ttydev_cdevsw as a more reliable method to figure out whether a
device node is a real TTY device node.
Obtained from: //depot/projects/mpsafetty/...
Reviewed by: thompsa
this eliminates some problems of locking, e.g, a thread lock is needed
but can not be used at that time. Only the process lock is needed now
for new field.
In particular following functions KPI results modified:
- bufobj_invalbuf()
- bufsync()
and BO_SYNC() "virtual method" of the buffer objects set.
Main consumers of bufobj functions are affected by this change too and,
in particular, functions which changed their KPI are:
- vinvalbuf()
- g_vfs_close()
Due to the KPI breakage, __FreeBSD_version will be bumped in a later
commit.
As a side note, please consider just temporary the 'curthread' argument
passing to VOP_SYNC() (in bufsync()) as it will be axed out ASAP
Reviewed by: kib
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
designed drivers would never hit, but was exposed in diving into
another problem...
When expanding the devclass array, free the old memory after updating
the pointer to the new memory. For the following single race case,
this helps:
allocate new memory
copy to new memory
free old memory
<interrupt> read pointer to freed memory
update pointer to new memory
Now we do
allocate new memory
copy to new memory
update pointer to new memory
free old memory
Which closes this problem, but doesn't even begin to address the
multicpu races, which all should be covered by Giant at the moment,
but likely aren't completely.
Note: reviewers were ok with this fix, but suggested the use case
wasn't one we wanted to encourage.
Reviewed by: jhb, scottl.
have_interp to TRUE. This allows the code in image activator to try
/libexec/ld-elf.so.1 as interpreter when newinterp is not found to
execute.
Reviewed by: peter
MFC after: 2 weeks (together with r175105)
descriptor pointer in unp_freerights: we can no longer recurse into
unp_gc due to unp_gc being invoked in a deferred way, but it's still
a good idea.
MFC after: 3 days
no data is ready, return 0 rather than blocking or returning EAGAIN.
This is consistent with the behavior of soreceive_generic (soreceive)
in earlier versions of FreeBSD, and restores this behavior for UDP.
Discussed with: jhb, sam
MFC after: 3 days
improperly invoking sosend(), soreceive(), and sopoll() instead of
attach either specialized or _generic() versions of those functions
to their pru_sosend, pru_soreceive, and pru_sopoll protosw methods.
MFC after: 3 days
booting from an MFS root (e.g. from an install CD) firmware_mountroot
can be called twice with the second call happening before the task
callback occurs; this results in the task structure contents being
corrupted because it was declared static.
Submitted by: marius (original version)
- Staticize and locally prototype functions uipc_ctloutput(), unp_dispose(),
unp_init(), and unp_externalize(), none of which have been required
outside of uipc_usrreq.c since uipc_proto.c was removed.
- Remove stale prototype for uipc_usrreq(), which has not existed in the
code since 1997
- Forward declare and staticize uipc_usrreqs structure in uipc_usrreq.c and
not un.h.
- Comment on why uipc_connect2() is still non-static -- it is used directly
by fifofs.
- Remove stale comments, tidy up whitespace.
MFC after: 3 days (where applicable)
from the vimage project, as per plan established at devsummit 08/08:
http://wiki.freebsd.org/Image/Notes200808DevSummit
Introduce INIT_VNET_*() initializer macros, VNET_FOREACH() iterator
macros, and CURVNET_SET() context setting macros, all currently
resolving to NOPs.
Prepare for virtualization of selected SYSCTL objects by introducing a
family of SYSCTL_V_*() macros, currently resolving to their global
counterparts, i.e. SYSCTL_V_INT() == SYSCTL_INT().
Move selected #defines from sys/sys/vimage.h to newly introduced header
files specific to virtualized subsystems (sys/net/vnet.h,
sys/netinet/vinet.h etc.).
All the changes are verified to have zero functional impact at this
point in time by doing MD5 comparision between pre- and post-change
object files(*).
(*) netipsec/keysock.c did not validate depending on compile time options.
Implemented by: julian, bz, brooks, zec
Reviewed by: julian, bz, brooks, kris, rwatson, ...
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
to store the socket address stored in the first mbuf in a packet chain.
This reduces contention on the lock and CPU system time in certain UDP
workloads.
Tested by: ps
Reviewed by: rwatson
MFC after: 1 week
- Update or remove comments that were left over from the original
soreceive_generic() implementation. Quite a few were misleading in the
context of the new code.
- Since soreceive_dgram() has a simpler structure, replace several gotos
with a while loop making the invariants more clear.
- In the blocking while loop, don't try to handle cases incompatible with
the loop invariant (since m is always NULL, don't check for and handle
non-NULL).
- Don't drop and re-acquire the socket buffer lock unnecessarily after
sbwait() returns, which may help reduce lock contention (etc).
- Assume PR_ATOMIC since we assert it at the top of the function.
MFC after: 3 days
setting TDF_INPANIC then it will never be rescheduled again. Wrap
setting the panic condition with the critical section.
Noted and reviewed by: tegge
MFC after: 1 week
The uminor() and umajor() functions have the same use in kernel space as
the minor() and major() functions in userspace. If we ever get rid of
the minor() function in kernel space, we could decide to just expose
minor() and major() to kernel space, making uminor() and umajor()
redundant.
There are two reasons why we want to have uminor() and umajor() in
<sys/types.h>:
- Having them close together prevents them from diverting. Even though
it's unlikely the definitions will change, it's a good habit to have
them at the same place.
- They don't really belong in kern_conf.c. kern_conf.c has been
liberated from dealing with device major and minor number handling.
The device_ids(9) manpage now lists the wrong #include's, because it
should only list <sys/types.h> now. I'm leaving it as it is now, because
I wonder if we should document them anyway. We're probably better off
documenting minor(3) and major(3).
After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.
This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.
Reviewed by: kib
I've had some reports in the past that opening an already opened TTY
through, for example, /dev/tty can fail with random error codes. Looking
at ttydev_open(), I can see there is a way `error' is returned without
initialising it. Even though I haven't had any confirmation this fixes
the bug, I'll fix it anyway.
Reported by: Andrzej Tobola <ato iem pw edu pl>
To prevent any further confusion about device minor and unit numbers,
we'd better just refer to device unit numbers. Many people still think
the numbers we show inside devfs have any relation to the numbers passed
to make_dev(9), which is not the case.
Discussed with: kib
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.
We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().
Reviewed by: kib
- Instead of using a syscall slot (370) just to get a function prototype
for lkmressys(), add an explicit function prototype to <sys/sysent.h>.
This also removes unused special case checks for 'lkmressys' from
makesyscalls.sh.
- Instead of having magic logic in makesyscalls.sh to only generate a
function prototype the first time 'lkmnosys' is seen, make 'NODEF'
always not generate a function prototype and include an explicit
prototype for 'lkmnosys' in <sys/sysent.h>.
- As a result of the fix in (2), update the LKM syscall entries in
the freebsd32 syscall table to use 'lkmnosys' rather than 'nosys'.
- Use NOPROTO for the __syscall() entry (198) in the native ABI. This
avoids the need for magic logic in makesyscalls.h to only generate
a function prototype the first time 'nosys' is encountered.
variable wait routines. DROP_GIANT() already manages that state in the
Giant interlock case.
- Assert that Giant is held when it is passed as a sleep interlock.
unmounts. When we upgrade a vnode lock from shared to exclusive during
a name cache lookup, fail the lookup with EBADF if the vnode is invalidated
while we are waiting for the exclusive lock.
Also, for correctness (though I'm not sure it can occur in practice),
downgrade an exclusively locked vnode if it should be share locked.
Tested by: pho
