sched: Fix some kernel-doc warnings

When building the htmldocs (in verbose mode), scripts/kernel-doc
reports the follwing type of warnings:

  Warning(kernel/sched/core.c:936): No description found for return value of 'task_curr'
  ...

Fix those by:

 - adding the missing descriptions
 - using "Return" sections for the descriptions

Signed-off-by: Yacine Belkadi <yacine.belkadi.1@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1373654747-2389-1-git-send-email-yacine.belkadi.1@gmail.com
[ While at it, fix the cpupri_set() explanation. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
iio:trigger: Fix use_count race condition

When using more than one trigger consumer it can happen that multiple threads
perform a read-modify-update cycle on 'use_count' concurrently. This can cause
updates to be lost and use_count can get stuck at non-zero value, in which case
the IIO core assumes that at least one thread is still running and will wait for
it to finish before running any trigger handlers again. This effectively renders
the trigger disabled and a reboot is necessary before it can be used again. To
fix this make use_count an atomic variable. Also set it to the number of
consumers before starting the first consumer, otherwise it might happen that
use_count drops to 0 even though not all consumers have been run yet.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Tested-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
iio: ti_am335x_adc: Fix wrong samples received on 1st read

Previously we tried to read data form ADC even before ADC sequencer
finished sampling. This led to wrong samples.
We now wait on ADC status register idle bit to be set.

Signed-off-by: Patil, Rachna <rachna@ti.com>
Signed-off-by: Zubair Lutfullah <zubair.lutfullah@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
KVM: s390: move kvm_guest_enter,exit closer to sie

Any uaccess between guest_enter and guest_exit could trigger a page fault,
the page fault handler would handle it as a guest fault and translate a
user address as guest address.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: s390: fix pfmf non-quiescing control handling

Fix the test within handle_pfmf() if the host has the NQ key-setting
facility installed.
Right now the code would incorrectly generate a program check in the
guest if the NQ control bit for a pfmf request was set and if the host
has the NQ key-setting facility installed.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
staging: zcache: fix "zcache=" kernel parameter

Commit 835f2f5 ("staging: zcache: enable zcache to be built/loaded as
a module") introduced an incorrect handling of "zcache=" parameter.

Inside zcache_comp_init() function, zcache_comp_name variable is
checked for being empty. If not empty, the above variable is tested
for being compatible with Crypto API. Unfortunately, after that
function ends unconditionally (by the "goto out" directive) and returns:
- non-zero value if verification succeeded, wrongly indicating an error
- zero value if verification failed, falsely informing that function
  zcache_comp_init() ended properly.

A solution to this problem is as following:
1. Move the "goto out" directive inside the "if (!ret)" statement
2. In case that crypto_has_comp() returned 0, change the value of ret
   to non-zero before "goto out" to indicate an error.

This patch replaces an earlier one from Michal Hocko (based on report
from Cristian Rodriguez):

	http://permalink.gmane.org/gmane.linux.kernel.mm/102484

It also addressed the same issue but didn't fix the zcache_comp_init()
for case when the compressor data passed to "zcache=" option was invalid
or unsupported.

Signed-off-by: Piotr Sarna <p.sarna@partner.samsung.com>
[bzolnier: updated patch description]
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: stable <stable@vger.kernel.org> # 3.10
Cc: Cristian Rodriguez <crrodriguez@opensuse.org>
Cc: Bob Liu <bob.liu@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sched: Ensure update_cfs_shares() is called for parents of continuously-running tasks

We typically update a task_group's shares within the dequeue/enqueue
path.  However, continuously running tasks sharing a CPU are not
subject to these updates as they are only put/picked.  Unfortunately,
when we reverted f269ae046 (in 17bc14b7), we lost the augmenting
periodic update that was supposed to account for this; resulting in a
potential loss of fairness.

To fix this, re-introduce the explicit update in
update_cfs_rq_blocked_load() [called via entity_tick()].

Reported-by: Max Hailperin <max@gustavus.edu>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/n/tip-9545m3apw5d93ubyrotrj31y@git.kernel.org
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
mutex: Fix w/w mutex deadlock injection

The check needs to be for > 1, because ctx->acquired is already incremented.
This will prevent ww_mutex_lock_slow from returning -EDEADLK and not locking
the mutex. It caused a lot of false gpu lockups on radeon with
CONFIG_DEBUG_WW_MUTEX_SLOWPATH=y because a function that shouldn't be able
to return -EDEADLK did.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/51F775B5.201@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
nl80211: fix another nl80211_fam.attrbuf race

This is similar to the race Linus had reported, but in this case
it's an older bug: nl80211_prepare_wdev_dump() uses the wiphy
index in cb->args[0] as it is and thus parses the message over
and over again instead of just once because 0 is the first valid
wiphy index. Similar code in nl80211_testmode_dump() correctly
offsets the wiphy_index by 1, do that here as well.

Cc: stable@vger.kernel.org
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cifs: extend the buffer length enought for sprintf() using

For cifs_set_cifscreds() in "fs/cifs/connect.c", 'desc' buffer length
is 'CIFSCREDS_DESC_SIZE' (56 is less than 256), and 'ses->domainName'
length may be "255 + '\0'".

The related sprintf() may cause memory overflow, so need extend related
buffer enough to hold all things.

It is also necessary to be sure of 'ses->domainName' must be less than
256, and define the related macro instead of hard code number '256'.

Signed-off-by: Chen Gang <gang.chen@asianux.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Scott Lovenberg <scott.lovenberg@gmail.com>
CC: <stable@vger.kernel.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Do not attempt to do cifs operations reading symlinks with SMB2

When use of symlinks is enabled (mounting with mfsymlinks option) to
non-Samba servers, we always tried to use cifs, even when we
were mounted with SMB2 or SMB3, which causes the server to drop the
network connection.

This patch separates out the protocol specific operations for cifs from
the code which recognizes symlinks, and fixes the problem where
with SMB2 mounts we attempt cifs operations to open and read
symlinks.  The next patch will add support for SMB2 for opening
and reading symlinks.  Additional followon patches will address
the similar problem creating symlinks.

Signed-off-by: Steve French <smfrench@gmail.com>
cifs: file: initialize oparms.reconnect before using it

In the cifs_reopen_file function, if the following statement is
asserted:

(tcon->unix_ext && cap_unix(tcon->ses) &&
            (CIFS_UNIX_POSIX_PATH_OPS_CAP &
            (tcon->fsUnixInfo.Capability)))

and we succeed to open with cifs_posix_open, the function jumps
to the label reopen_success and checks for oparms.reconnect
which is not initialized.

This issue has been reported by scan.coverity.com

Signed-off-by: Andi Shyti <andi@etezian.org>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
usb: core: don't try to reset_device() a port that got just disconnected

The USB hub driver's event handler contains a check to catch SuperSpeed
devices that transitioned into the SS.Inactive state and tries to fix
them with a reset. It decides whether to do a plain hub port reset or
call the usb_reset_device() function based on whether there was a device
attached to the port.

However, there are device/hub combinations (found with a JetFlash
Transcend mass storage stick (8564:1000) on the root hub of an Intel
LynxPoint PCH) which can transition to the SS.Inactive state on
disconnect (and stay there long enough for the host to notice). In this
case, above-mentioned reset check will call usb_reset_device() on the
stale device data structure. The kernel will send pointless LPM control
messages to the no longer connected device address and can even cause
several 5 second khubd stalls on some (buggy?) host controllers, before
finally accepting the device's fate amongst a flurry of error messages.

This patch makes the choice of reset dependent on the port status that
has just been read from the hub in addition to the existence of an
in-kernel data structure for the device, and only proceeds with the more
extensive reset if both are valid.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
usb: xhci: add missing dma-mapping.h includes

A randconfig build hit the following build errors because xhci.c and
xhci-mem.c use dma mapping functions but don't include
<linux/dma-mapping.h>. Add the missing includes to fix the build errors.

drivers/usb/host/xhci.c In function 'xhci_gen_setup':
drivers/usb/host/xhci.c +4872 : error: implicit declaration of function 'dma_set_mask'
drivers/usb/host/xhci.c +4872 : error: implicit declaration of function 'DMA_BIT_MASK'

drivers/usb/host/xhci-mem.c In function 'xhci_free_stream_ctx':
drivers/usb/host/xhci-mem.c +435 : error: implicit declaration of function 'dma_free_coherent'
drivers/usb/host/xhci-mem.c In function 'xhci_alloc_stream_ctx':
drivers/usb/host/xhci-mem.c +463 : error: implicit declaration of function 'dma_alloc_coherent'

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
cifs: fix bad error handling in crypto code

Jarod reported an Oops like when testing with fips=1:

CIFS VFS: could not allocate crypto hmacmd5
CIFS VFS: could not crypto alloc hmacmd5 rc -2
CIFS VFS: Error -2 during NTLMSSP authentication
CIFS VFS: Send error in SessSetup = -2
BUG: unable to handle kernel NULL pointer dereference at 000000000000004e
IP: [<ffffffff812b5c7a>] crypto_destroy_tfm+0x1a/0x90
PGD 0
Oops: 0000 [#1] SMP
Modules linked in: md4 nls_utf8 cifs dns_resolver fscache kvm serio_raw virtio_balloon virtio_net mperf i2c_piix4 cirrus drm_kms_helper ttm drm i2c_core virtio_blk ata_generic pata_acpi
CPU: 1 PID: 639 Comm: mount.cifs Not tainted 3.11.0-0.rc3.git0.1.fc20.x86_64 #1
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
task: ffff88007bf496e0 ti: ffff88007b080000 task.ti: ffff88007b080000
RIP: 0010:[<ffffffff812b5c7a>]  [<ffffffff812b5c7a>] crypto_destroy_tfm+0x1a/0x90
RSP: 0018:ffff88007b081d10  EFLAGS: 00010282
RAX: 0000000000001f1f RBX: ffff880037422000 RCX: ffff88007b081fd8
RDX: 000000000000001f RSI: 0000000000000006 RDI: fffffffffffffffe
RBP: ffff88007b081d30 R08: ffff880037422000 R09: ffff88007c090100
R10: 0000000000000000 R11: 00000000fffffffe R12: fffffffffffffffe
R13: ffff880037422000 R14: ffff880037422000 R15: 00000000fffffffe
FS:  00007fc322f4f780(0000) GS:ffff88007fc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 000000000000004e CR3: 000000007bdaa000 CR4: 00000000000006e0
Stack:
 ffffffff81085845 ffff880037422000 ffff8800375e7400 ffff880037422000
 ffff88007b081d48 ffffffffa0176022 ffff880037422000 ffff88007b081d60
 ffffffffa015c07b ffff880037600600 ffff88007b081dc8 ffffffffa01610e1
Call Trace:
 [<ffffffff81085845>] ? __cancel_work_timer+0x75/0xf0
 [<ffffffffa0176022>] cifs_crypto_shash_release+0x82/0xf0 [cifs]
 [<ffffffffa015c07b>] cifs_put_tcp_session+0x8b/0xe0 [cifs]
 [<ffffffffa01610e1>] cifs_mount+0x9d1/0xad0 [cifs]
 [<ffffffffa014ff50>] cifs_do_mount+0xa0/0x4d0 [cifs]
 [<ffffffff811ab6e9>] mount_fs+0x39/0x1b0
 [<ffffffff811c466f>] vfs_kern_mount+0x5f/0xf0
 [<ffffffff811c6a9e>] do_mount+0x23e/0xa20
 [<ffffffff811c66e6>] ? copy_mount_options+0x36/0x170
 [<ffffffff811c7303>] SyS_mount+0x83/0xc0
 [<ffffffff8165c8d9>] system_call_fastpath+0x16/0x1b
Code: eb 9e 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 66 66 90 55 48 89 e5 41 55 41 54 49 89 fc 53 48 83 ec 08 48 85 ff 74 46 <48> 83 7e 48 00 48 8b 5e 50 74 4b 48 89 f7 e8 83 fc ff ff 4c 8b
RIP  [<ffffffff812b5c7a>] crypto_destroy_tfm+0x1a/0x90
 RSP <ffff88007b081d10>
CR2: 000000000000004e

The cifs code allocates some crypto structures. If that fails, it
returns an error, but it leaves the pointers set to their PTR_ERR
values. Then later when it tries to clean up, it sees that those values
are non-NULL and then passes them to the routine that frees them.

Fix this by setting the pointers to NULL after collecting the error code
in this situation.

Cc: Sachin Prabhu <sprabhu@redhat.com>
Reported-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
cifs: set sb->s_d_op before calling d_make_root()

Currently, the s_root dentry doesn't get its d_op pointer set to
anything. This breaks lookups in the root of case-insensitive mounts
since that relies on having d_hash and d_compare routines that know to
treat the filename as case-insensitive.

cifs.ko has been broken this way for a long time, but commit 1c929cfe6
("switch cifs"), added a cryptic comment which is removed in the patch
below, which makes me wonder if this was done deliberately for some
reason. It's not clear to me why we'd want the s_root not to have d_op
set properly.

It may have something to do with d_automount or d_revalidate on the
root, but my suspicion in looking over the code is that Al was just
trying to preserve the existing behavior when changing this code over to
use s_d_op.

This patch changes it so that we set s_d_op before calling d_make_root
and removes the comment. I tested mounting, accessing and unmounting
several types of shares (including DFS referrals) and everything still
seemed to work OK afterward. I could be missing something however, so
please do let me know if I am.

Reported-by: Jan-Marek Glogowski <glogow@fbihome.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
mac80211: fix infinite loop in ieee80211_determine_chantype

Commit "3d9646d mac80211: fix channel selection bug" introduced a possible
infinite loop by moving the out target above the chandef_downgrade
while loop.  When we downgrade to NL80211_CHAN_WIDTH_20_NOHT, we jump
back up to re-run the while loop...indefinitely.  Replace goto with
break and carry on.  This may not be sufficient to connect to the AP,
but will at least keep the cpu from livelocking.  Thanks to Derek Atkins
as an extra pair of debugging eyes.

Cc: stable@kernel.org
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: don't wait for TX status forever

TX status notification can get lost, or the frames could
get stuck on the queue, so don't wait for the callback
from the driver forever and instead time out after half
a second.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: ignore HT primary channel while connected

While we're connected, the AP shouldn't change the primary channel
in the HT information. We checked this, and dropped the connection
if it did change it.

Unfortunately, this is causing problems on some APs, e.g. on the
Netgear WRT610NL: the beacons seem to always contain a bad channel
and if we made a connection using a probe response (correct data)
we drop the connection immediately and can basically not connect
properly at all.

Work around this by ignoring the HT primary channel information in
beacons if we're already connected.

Also print out more verbose messages in the other situations to
help diagnose similar bugs quicker in the future.

Cc: stable@vger.kernel.org [3.10]
Acked-by: Andy Isaacson <adi@hexapodia.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: fix P2P GO interface teardown

When a P2P GO interface goes down, cfg80211 doesn't properly
tear it down, leading to warnings later. Add the GO interface
type to the enumeration to tear it down like AP interfaces.
Otherwise, we leave it pending and mac80211's state can get
very confused, leading to warnings later.

Cc: stable@vger.kernel.org
Reported-by: Ilan Peer <ilan.peer@intel.com>
Tested-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>