Being a hash table, hlist is the best option.

There is currently some ugliness were we treat "->next == NULL" as
a special case to avoid having to initialise the whole array.
This change nicely gets rid of that case.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Code like:

  switch(xxx) {
  case -error1:
  case -error2:
     ..
     return;
  case 0:
     stuff;
  }

  can more naturally be written:

  if (xxx < 0)
      return;

  stuff;
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The idmap code manages request deferal by waiting for a reply from
userspace rather than putting the NFS request on a queue to be retried
from the start.
Now that the common deferal code does this there is no need for the
special code in idmap.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Now that a slight delay in getting a reply to an upcall doesn't
require deferring of requests, request deferral for all NFSv4
requests - the concept doesn't really fit with the v4 model.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

If we drop a request in the sunrpc layer, either due kmalloc failure,
or due to a cache miss when we could not queue the request for later
replay, then close the connection to encourage the client to retry sooner.

Note that if the drop happens in the NFS layer, NFSERR_JUKEBOX
(aka NFS4ERR_DELAY) is returned to guide the client concerning
replay.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The last_close field of a cache_detail is initialized to zero, so the
condition

	detail->last_close < seconds_since_boot() - 30

may be false even for a cache that was never opened.

However, we want to immediately fail upcalls to caches that were never
opened: in the case of the auth_unix_gid cache, especially, which may
never be opened by mountd (if the --manage-gids option is not set), we
want to fail the upcall immediately.  Otherwise client requests will be
dropped unnecessarily on reboot.

Also document these conditions.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Without some client-side fixes, server testing is currently difficult.

The NFSv4 client's callback server calls svc_gss_principal(), which
is defined in the auth_rpcgss.ko

The NFSv4 server has the same dependency, and in addition calls
svcauth_gss_flavor(), gss_mech_get_by_pseudoflavor(),
gss_pseudoflavor_to_service() and gss_mech_put() from the same module.

The module auth_rpcgss itself has no dependencies aside from sunrpc,
so we only need to select RPCSEC_GSS.
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Hi,

An NFS client executes a statfs("file", &buff) call.
"file" exists / existed, the client has read / written it,
but it has already closed it.

user_path(pathname, &path) looks up "file" successfully in the
directory-cache  and restarts the aging timer of the directory-entry.
Even if "file" has already been removed from the server, because the
lookupcache=positive option I use, keeps the entries valid for a while.

nfs_statfs() returns ESTALE if "file" has already been removed from the
server.

If the user application repeats the statfs("file", &buff) call, we
are stuck: "file" remains young forever in the directory-cache.
Signed-off-by: Zoltan Menyhart  <Zoltan.Menyhart@bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

The maximum size of the authcache is now set to 1024 (10 bits),
but on our server we need at least 4096 (12 bits). Increase
MAX_HASHTABLE_BITS to 14. This is a maximum of 16384 entries,
each containing a pointer (8 bytes on x86_64). This is
exactly the limit of kmalloc() (128K).
Signed-off-by: Miquel van Smoorenburg <mikevs@xs4all.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

spkm3 miss returning error to up layer when import security context,
it may be return ok though it has failed to import security context.
Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

krb5 miss returning error to up layer when import security context,
it may be return ok though it has failed to import security context.
Signed-off-by: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The do_vfs_lock function on fs/nfs/file.c is only called if NLM is
not being used, via the -onolock mount option. Therefore it cannot
really be "out of sync with lock manager" when the local locking
function called returns an error, as there will be no corresponding
call to the NLM. For details, simply check the if/else on do_setlk
and do_unlk on fs/nfs/file.c.
Signed-Off-By: Fabio Olive Leite <fleite@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

This is just a minor cleanup: net/sunrpc/clnt.c clarifies the rpc client
state machine by commenting each state and by laying out the functions
implementing each state in the order that each state is normally
executed (in the absence of errors).

The previous patch "Fix null dereference in call_allocate" changed the
order of the states.  Move the functions and update the comments to
reflect the change.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

There is a race between rpc_info_open and rpc_release_client()
in that nothing stops a process from opening the file after
the clnt->cl_kref goes to zero.

Fix this by using atomic_inc_unless_zero()...
Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

If rpc_queue_upcall() adds a new upcall to the rpci->pipe list just
after rpc_pipe_release calls rpc_purge_list(), but before it calls
gss_pipe_release (as rpci->ops->release_pipe(inode)), then the latter
will free a message without deleting it from the rpci->pipe list.

We will be left with a freed object on the rpc->pipe list.  Most
frequent symptoms are kernel crashes in rpc.gssd system calls on the
pipe in question.
Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

In call_allocate we need to reach the auth in order to factor au_cslack
into the allocation.

As of a17c2153 "SUNRPC: Move the bound
cred to struct rpc_rqst", call_allocate attempts to do this by
dereferencing tk_client->cl_auth, however this is not guaranteed to be
defined--cl_auth can be zero in the case of gss context destruction (see
rpc_free_auth).

Reorder the client state machine to bind credentials before allocating,
so that we can instead reach the auth through the cred.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Fix docbook templates that reference files that do not contain the
expected kernel-doc notation.

Fixes these warnings:

  Warning(arch/x86/include/asm/unaligned.h): no structured comments found
  Warning(lib/vsprintf.c): no structured comments found

These cause errors in the generated html output, like below, so drop
these lines.

  Name
  arch/x86/include/asm/unaligned.h - Document generation inconsistency
  Oops
  Warning
  The template for this document tried to insert the structured comment from the file arch/x86/include/asm/unaligned.h at this point, but none was found. This dummy section is inserted to allow generation to continue.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When you don't use !E or !I but only !F, then it's very easy to miss
including some functions, structs etc.  in documentation.  To help
finding which ones were missed, allow printing out the unused ones as
warnings.

For example, using this on mac80211 yields a lot of warnings like this:

  Warning: didn't use docs for DOC: mac80211 workqueue
  Warning: didn't use docs for ieee80211_max_queues
  Warning: didn't use docs for ieee80211_bss_change
  Warning: didn't use docs for ieee80211_bss_conf

when generating the documentation for it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

There are valid attributes that could have upper case letters, but we
still want to remove, like for example
	__attribute__((aligned(NETDEV_ALIGN)))
as encountered in the wireless code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM / Hibernate: Avoid hitting OOM during preallocation of memory
  PM QoS: Correct pr_debug() misuse and improve parameter checks
  PM: Prevent waiting forever on asynchronous resume after failing suspend

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] fix use-after-free in scsi_init_io()
  [SCSI] sd: fix medium-removal bug
  [SCSI] qla2xxx: Update version number to 8.03.04-k0.
  [SCSI] qla2xxx: Check for empty slot in request queue before posting Command type 6 request.
  [SCSI] qla2xxx: Cover UNDERRUN case where SCSI status is set.
  [SCSI] qla2xxx: Correctly set fw hung and complete only waiting mbx.
  [SCSI] qla2xxx: Reset seconds_since_last_heartbeat correctly.
  [SCSI] qla2xxx: make rport deletions explicit during vport removal
  [SCSI] qla2xxx: Fix vport delete issues
  [SCSI] sd, sym53c8xx: Remove warnings after vsprintf %pV introducation.
  [SCSI] Fix warning: zero-length gnu_printf format string
  [SCSI] hpsa: disable doorbell reset on reset_devices
  [SCSI] be2iscsi: Fix for Login failure
  [SCSI] fix bio.bi_rw handling

There is a problem in hibernate_preallocate_memory() that it calls
preallocate_image_memory() with an argument that may be greater than
the total number of available non-highmem memory pages.  If that's
the case, the OOM condition is guaranteed to trigger, which in turn
can cause significant slowdown to occur during hibernation.

To avoid that, make preallocate_image_memory() adjust its argument
before calling preallocate_image_pages(), so that the total number of
saveable non-highem pages left is not less than the minimum size of
a hibernation image.  Change hibernate_preallocate_memory() to try to
allocate from highmem if the number of pages allocated by
preallocate_image_memory() is too low.

Modify free_unnecessary_pages() to take all possible memory
allocation patterns into account.
Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Tested-by: M. Vefa Bicakci <bicave@superonline.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (28 commits)
  ipheth: remove incorrect devtype to WWAN
  MAINTAINERS: Add CAIF
  sctp: fix test for end of loop
  KS8851: Correct RX packet allocation
  udp: add rehash on connect()
  net: blackhole route should always be recalculated
  ipv4: Suppress lockdep-RCU false positive in FIB trie (3)
  niu: Fix kernel buffer overflow for ETHTOOL_GRXCLSRLALL
  ipvs: fix active FTP
  gro: Re-fix different skb headrooms
  via-velocity: Turn scatter-gather support back off.
  ipv4: Fix reverse path filtering with multipath routing.
  UNIX: Do not loop forever at unix_autobind().
  PATCH: b44 Handle RX FIFO overflow better (simplified)
  irda: off by one
  3c59x: Fix deadlock in vortex_error()
  netfilter: discard overlapping IPv6 fragment
  ipv6: discard overlapping fragment
  net: fix tx queue selection for bridged devices implementing select_queue
  bonding: Fix jiffies overflow problems (again)
  ...

Fix up trivial conflicts due to the same cgroup API thinko fix going
through both Andrew and the networking tree.  However, there were small
differences between the two, with Andrew's version generally being the
nicer one, and the one I merged first. So pick that one.

Conflicts in: include/linux/cgroup.h and kernel/cgroup.c

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc: Kill all BKL usage.

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, tsc: Fix a preemption leak in restore_sched_clock_state()
  sched: Move sched_avg_update() to update_cpu_load()

Doh, a real life genuine preemption leak..

This caused a suspend failure.

Reported-bisected-and-tested-by-the-invaluable: Jeff Chua <jeff.chua.linux@gmail.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Nico Schottelius <nico-linux-20100709@schottelius.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Florian Pritz <flo@xssn.at>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: <stable@kernel.org> # Greg, please apply after: cd7240c0 ("x86, tsc, sched: Recompute cyc2ns_offset's during resume from")
sleep states
LKML-Reference: <1284150773.402.122.camel@laptop>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

* 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel:
  drm/i915: don't enable self-refresh on Ironlake
  drm/i915: Double check that the wait_request is not pending before warning
  Revert "drm/i915: Warn if we run out of FIFO space for a mode"
  Revert "drm/i915: Allow LVDS on pipe A on gen4+"
  Revert "drm/i915: Enable RC6 on Ironlake."

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: log IO completion workqueue is a high priority queue
  xfs: prevent reading uninitialized stack memory

A real life genuine preemption leak..
Reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Correct some pr_debug() misuse and add a stronger parameter check to
pm_qos_write() for the ASCII hex value case.  Thanks to Dan Carpenter
for pointing out the problem!
Signed-off-by: mark gross <markgross@thegnar.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

The workqueue implementation in 2.6.36-rcX has changed, resulting
in the workqueues no longer having dedicated threads for work
processing. This has caused severe livelocks under heavy parallel
create workloads because the log IO completions have been getting
held up behind metadata IO completions.  Hence log commits would
stall, memory allocation would stall because pages could not be
cleaned, and lock contention on the AIL during inode IO completion
processing was being seen to slow everything down even further.

By making the log Io completion workqueue a high priority workqueue,
they are queued ahead of all data/metadata IO completions and
processed before the data/metadata completions. Hence the log never
gets stalled, and operations needed to clean memory can continue as
quickly as possible. This avoids the livelock conditions and allos
the system to keep running under heavy load as per normal.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>

An execve with a very large total of argument/environment strings
can take a really long time in the execve system call.  It runs
uninterruptibly to count and copy all the strings.  This change
makes it abort the exec quickly if sent a SIGKILL.

Note that this is the conservative change, to interrupt only for
SIGKILL, by using fatal_signal_pending().  It would be perfectly
correct semantics to let any signal interrupt the string-copying in
execve, i.e. use signal_pending() instead of fatal_signal_pending().
We'll save that change for later, since it could have user-visible
consequences, such as having a timer set too quickly make it so that
an execve can never complete, though it always happened to work before.
Signed-off-by: Roland McGrath <roland@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds a preemption point during the copying of the argument and
environment strings for execve, in copy_strings().  There is already
a preemption point in the count() loop, so this doesn't add any new
points in the abstract sense.

When the total argument+environment strings are very large, the time
spent copying them can be much more than a normal user time slice.
So this change improves the interactivity of the rest of the system
when one process is doing an execve with very large arguments.
Signed-off-by: Roland McGrath <roland@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The CONFIG_STACK_GROWSDOWN variant of setup_arg_pages() does not
check the size of the argument/environment area on the stack.
When it is unworkably large, shift_arg_pages() hits its BUG_ON.
This is exploitable with a very large RLIMIT_STACK limit, to
create a crash pretty easily.

Check that the initial stack is not too large to make it possible
to map in any executable.  We're not checking that the actual
executable (or intepreter, for binfmt_elf) will fit.  So those
mappings might clobber part of the initial stack mapping.  But
that is just userland lossage that userland made happen, not a
kernel problem.
Signed-off-by: Roland McGrath <roland@redhat.com>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'kvm-updates/2.6.36' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Perform hardware_enable in CPU_STARTING callback
  KVM: i8259: fix migration
  KVM: fix i8259 oops when no vcpus are online
  KVM: x86 emulator: fix regression with cmpxchg8b on i386 hosts

Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  tracing: t_start: reset FTRACE_ITER_HASH in case of seek/pread
  perf symbols: Fix multiple initialization of symbol system
  perf: Fix CPU hotplug
  perf, trace: Fix module leak
  tracing/kprobe: Fix handling of C-unlike argument names
  tracing/kprobes: Fix handling of argument names
  perf probe: Fix handling of arguments names
  perf probe: Fix return probe support
  tracing/kprobe: Fix a memory leak in error case
  tracing: Do not allow llseek to set_ftrace_filter

Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership
of the parent process's session keyring whether or not the parent has a session
keyring [CVE-2010-2960].

This results in the following oops:

  BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0
  IP: [<ffffffff811ae4dd>] keyctl_session_to_parent+0x251/0x443
  ...
  Call Trace:
   [<ffffffff811ae2f3>] ? keyctl_session_to_parent+0x67/0x443
   [<ffffffff8109d286>] ? __do_fault+0x24b/0x3d0
   [<ffffffff811af98c>] sys_keyctl+0xb4/0xb8
   [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b

if the parent process has no session keyring.

If the system is using pam_keyinit then it mostly protected against this as all
processes derived from a login will have inherited the session keyring created
by pam_keyinit during the log in procedure.

To test this, pam_keyinit calls need to be commented out in /etc/pam.d/.
Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Tavis Ormandy <taviso@cmpxchg8b.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>