Since we clear QUEUE_STARTED in rt2x00queue_stop_queue(), following
call to rt2x00queue_pause_queue() reduce to noop, i.e we do not
stop queue in mac80211.

To fix that introduce rt2x00queue_pause_queue_nocheck() function,
which will stop queue in mac80211 directly.

Note that rt2x00_start_queue() explicitly set QUEUE_PAUSED bit.

Note also that reordering operations i.e. first call to
rt2x00queue_pause_queue() and then clear QUEUE_STARTED bit, will race
with rt2x00queue_unpause_queue(), so calling ieee80211_stop_queue()
directly is the only available solution to fix the problem without
major rework.

Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

When the brcmfmac device is physically removed cfg80211 gives a
warning upon unregistering the net device (see below).

[23052.390197] WARNING: CPU: 0 PID: 30 at net/wireless/core.c:937 cfg80211_netdev_notifier_call+0x164/0x600 [cfg80211]()
[23052.400843] Modules linked in: brcmfmac(O) brcmutil(O) cfg80211(O) pl2303 usbserial binfmt_misc snd_hda_codec_hdmi snd_hda_codec_idt snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event lpc_ich snd_seq snd_timer snd_seq_device snd psmouse mfd_core serio_raw soundcore snd_page_alloc intel_ips dell_laptop dell_wmi sparse_keymap dcdbas nouveau ttm drm_kms_helper drm i2c_algo_bit mxm_wmi ahci libahci sdhci_pci firewire_ohci firewire_core sdhci crc_itu_t mmc_core intel_agp intel_gtt e1000e ptp pps_core agpgart video [last unloaded: brcmfmac]
[23052.452987] CPU: 0 PID: 30 Comm: khubd Tainted: G           O 3.11.0-rc1-wl-testing-lockdep-00002-g41cc093-dirty #1
[23052.463480] Hardware name: Dell Inc. Latitude E6410/07XJP9, BIOS A07 02/15/2011
[23052.470852]  00000000 00000000 f4efdc18 c1522e3d f845bed2 f4efdc48 c103fbe4 c16a9254
[23052.478762]  00000000 0000001e f845bed2 000003a9 f841da44 f841da44 f3790004 f25539c0
[23052.486741]  e2700200 f4efdc58 c103fc22 00000009 00000000 f4efdcc0 f841da44 00000002
[23052.494712] Call Trace:
[23052.497165]  [<c1522e3d>] dump_stack+0x4b/0x66
[23052.501685]  [<c103fbe4>] warn_slowpath_common+0x84/0xa0
[23052.507085]  [<f841da44>] ? cfg80211_netdev_notifier_call+0x164/0x600 [cfg80211]
[23052.514542]  [<f841da44>] ? cfg80211_netdev_notifier_call+0x164/0x600 [cfg80211]
[23052.521981]  [<c103fc22>] warn_slowpath_null+0x22/0x30
[23052.527191]  [<f841da44>] cfg80211_netdev_notifier_call+0x164/0x600 [cfg80211]
[23052.534494]  [<c150abe8>] ? packet_notifier+0xc8/0x1d0
[23052.539703]  [<c150abfc>] ? packet_notifier+0xdc/0x1d0
[23052.544880]  [<c150ab20>] ? packet_seq_stop+0x30/0x30
[23052.550002]  [<c152d655>] notifier_call_chain+0x45/0x60
[23052.555298]  [<c106839f>] raw_notifier_call_chain+0x1f/0x30
[23052.560963]  [<c143c693>] call_netdevice_notifiers_info+0x33/0x70
[23052.567153]  [<c1459869>] ? qdisc_destroy+0x99/0xb0
[23052.572116]  [<c143c6e3>] call_netdevice_notifiers+0x13/0x20
[23052.577861]  [<c143df93>] rollback_registered_many+0xf3/0x1d0
[23052.583687]  [<c1524cfc>] ? mutex_lock_nested+0x25c/0x350
[23052.589150]  [<c143e0f4>] rollback_registered+0x24/0x40
[23052.594445]  [<c143e15f>] unregister_netdevice_queue+0x4f/0xb0
[23052.600344]  [<c143e299>] unregister_netdev+0x19/0x30
[23052.605484]  [<f865b38f>] brcmf_del_if+0xbf/0x160 [brcmfmac]
[23052.611223]  [<f865b7ae>] brcmf_detach+0x5e/0xd0 [brcmfmac]
[23052.616881]  [<f8667413>] brcmf_usb_disconnect+0x63/0xa0 [brcmfmac]
[23052.623217]  [<c13e09aa>] usb_unbind_interface+0x4a/0x180

When the device is physically connected the driver sends a disassoc
command to the device and response triggers the driver to inform cfg80211
about it. However, with the device removed the disassoc command fails.
This patch adds a call to cfg80211_disconnected() when that command fails.

The warning was added by commit below and also cleans up, but better
doing it in the driver if only to get rid of the warning.

commit f9bef3df
Author: Ben Greear <greearb@candelatech.com>
Date:   Wed Jun 19 14:06:26 2013 -0700

    wireless: check for dangling wdev->current_bss pointer

Cc: Ben Greear <greearb@candelatech.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Both type and pkt_len variables are in host endian and these should be in
Little Endian in the payload.
Signed-off-by: Tomasz Moń <desowin@gmail.com>
Acked-by: Bing Zhao <bzhao@marvell.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

To avoid ending up in a NULL-pointer access, the function
brcmf_txflowblock_if() should only be called for interfaces
that have a netdev associated with it.
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

If the transmit fails because there are no hanger slots or
any other reason and the packet was an EAPOL packet the
pending counter should be decreased although it was not
transmitted so the driver does not end up in a dead-lock.
Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Building driver wil6210 in 3.10 and 3.11 kernels yields the following errors:

  CC [M]  drivers/net/wireless/ath/wil6210/debugfs.o
drivers/net/wireless/ath/wil6210/debugfs.c: In function 'wil_print_ring':
drivers/net/wireless/ath/wil6210/debugfs.c:163:11: error: pointer targets in passing argument 5 of 'hex_dump_to_buffer' differ in signedness [-Werror=pointer-sign]
           false);
           ^
In file included from include/linux/kernel.h:13:0,
                 from include/linux/cache.h:4,
                 from include/linux/time.h:4,
                 from include/linux/stat.h:18,
                 from include/linux/module.h:10,
                 from drivers/net/wireless/ath/wil6210/debugfs.c:17:
include/linux/printk.h:361:13: note: expected 'char *' but argument is of type 'unsigned char *'
 extern void hex_dump_to_buffer(const void *buf, size_t len,
             ^
drivers/net/wireless/ath/wil6210/debugfs.c: In function 'wil_txdesc_debugfs_show':
drivers/net/wireless/ath/wil6210/debugfs.c:429:10: error: pointer targets in passing argument 5 of 'hex_dump_to_buffer' differ in signedness [-Werror=pointer-sign]
          sizeof(printbuf), false);
          ^
In file included from include/linux/kernel.h:13:0,
                 from include/linux/cache.h:4,
                 from include/linux/time.h:4,
                 from include/linux/stat.h:18,
                 from include/linux/module.h:10,
                 from drivers/net/wireless/ath/wil6210/debugfs.c:17:
include/linux/printk.h:361:13: note: expected 'char *' but argument is of type 'unsigned char *'
 extern void hex_dump_to_buffer(const void *buf, size_t len,
             ^
cc1: all warnings being treated as errors
make[5]: *** [drivers/net/wireless/ath/wil6210/debugfs.o] Error 1
make[4]: *** [drivers/net/wireless/ath/wil6210] Error 2
make[3]: *** [drivers/net/wireless/ath] Error 2
make[2]: *** [drivers/net/wireless] Error 2
make[1]: *** [drivers/net] Error 2
make: *** [drivers] Error 2

These errors are fixed by changing the type of the buffer from "unsigned char *" to "char *".
Reported-by: Thomas Fjellstrom <thomas@fjellstrom.ca>
Tested-by: Thomas Fjellstrom <thomas@fjellstrom.ca>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>  [3.10]
Cc: Thomas Fjellstrom <thomas@fjellstrom.ca>
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

In monitor mode, priv->vif is NULL, but at one point in the receive path we
blindly attempt to dereference it.  Add a test to prevent this.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Currently ath9k_htc will reboot firmware only if interface was
ever started. Which lead to the problem in case where interface
was never started but module need to be reloaded.

This patch will partially fix bug "ath9k_htc: Target is unresponsive"
https://github.com/qca/open-ath9k-htc-firmware/issues/1

Reproduction case:
- plug adapter
- make sure nothing will touch it. Stop Networkmanager or blacklist mac address of this adapter.
- rmmod ath9k_htc; sleep 1; modprobe ath9k_htc
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Currently we configure harwdare and clock, only after
interface start. In this case, if we reload module or
reboot PC without configuring adapter, firmware will freeze.
There is no software way to reset adpter.

This patch add initial configuration and set it in
disabled state, to avoid this freeze. Behaviour of this patch
should be similar to: ifconfig wlan0 up; ifconfig wlan0 down.

Bug: https://github.com/qca/open-ath9k-htc-firmware/issues/1Tested-by: Bo Shi <cnshibo@gmail.com>
Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

During tear down (e.g. mwifiex_sdio_remove during system suspend),
mwifiex left IRQs enabled for a significant period of time when it was
unable to handle them correctly. This caused interrupt storms and
interfered with the bluetooth interface on the same SDIO card.

Solve this by disabling interrupts at the point when they can no longer
be handled correctly, which is at the start of mwifiex_remove_card().

For cleanliness, we now enable interrupts in the mwifiex_add_card() path,
to be symmetrical with the disabling of interrupts. We also couple the
registration of the sdio IRQ handler with the actual enable/disable of
interrupts at the hardware level.

I also removed a write to this register in mwifiex_init_sdio which seemed
pointless and won't cause any ill effects now that we only register
the SDIO IRQ handler when we are ready to accept interrupts.

Includes some corrections from Amitkumar Karwar.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Acked-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

The multicast search bit is disabled for the AR9003
family, but this is required for AR9002 too. Fix this in
the INI override routine.
Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

The present build configuration for the rtlwifi family of drivers will
fail under two known conditions:

(1) If rtlwifi is selected without selecting any of the dependent drivers,
    there are errors in the build.
(2) If the PCI drivers are built into the kernel and the USB drivers are modules,
    or vice versa, there are missing globals.

The first condition is fixed by never building rtlwifi unless at least one
of the device drivers is selected. The second failure is fixed by splitting
the PCI and USB codes out of rtlwifi, and creating their own mini drivers.
If the drivers that use them are modules, they will also be modules.

Although a number of files are touched by this patch, only Makefile and Kconfig
have undergone significant changes. The only modifications to the other files
were to export entry points needed by the new rtl_pci and rtl_usb units, or to
rename two variables that had names that were likely to cause namespace collisions.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>  [Condition 1]
Reported-by: Ben Hutchings <bhutchings@solarflare.com> [Condition 2]
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Bit 32 was always set which looks to have been accidental,
according to git history.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

If NO_DMA=y:

drivers/built-in.o: In function `rt2x00queue_unmap_skb':
drivers/net/wireless/rt2x00/rt2x00queue.c:129: undefined reference to `dma_unmap_single'
drivers/net/wireless/rt2x00/rt2x00queue.c:133: undefined reference to `dma_unmap_single'
drivers/built-in.o: In function `rt2x00queue_map_txskb':
drivers/net/wireless/rt2x00/rt2x00queue.c:112: undefined reference to `dma_map_single'
drivers/net/wireless/rt2x00/rt2x00queue.c:115: undefined reference to `dma_mapping_error'
drivers/built-in.o: In function `rt2x00queue_alloc_rxskb':
drivers/net/wireless/rt2x00/rt2x00queue.c:93: undefined reference to `dma_map_single'
drivers/net/wireless/rt2x00/rt2x00queue.c:95: undefined reference to `dma_mapping_error'
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: linux-wireless@vger.kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

The ARM OABI and EABI disagree on the alignment of structures
with small members, so module init tools may interpret the
ssb device table incorrectly, as shown  by this warning when
building the b43 device driver in an OABI kernel:

FATAL: drivers/net/wireless/b43/b43: sizeof(struct ssb_device_id)=6 is
not a modulo of the size of section __mod_ssb_device_table=88.

Forcing the default (EABI) alignment on the structure makes this
problem go away. Since the ssb_device_id may have the same problem,
better fix both structures.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k_hif_usb_probe() requests firmware asynchronically and
there is some initialization postponed till firmware is ready.
In particular, ath9k_hif_usb_firmware_cb() callback initializes
hif_dev->tx.tx_buf and hif_dev->tx.tx_pending lists.

At the same time, ath9k_hif_usb_suspend() iterates that lists through
ath9k_hif_usb_dealloc_urbs(). If suspend happens before request_firmware_nowait()
callback is called, it can lead to oops.

Similar issue could be in ath9k_hif_usb_disconnect(), but it is prevented
using hif_dev->fw_done completion and HIF_USB_READY flag. The patch extends
this approach to suspend() as well.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

When dropping packets that have gone far enough into the tx path, the
pending frame counter needs to be decreased.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Commit a269913c entitled "rtlwifi: Rework rtl_lps_leave() and
rtl_lps_enter() to use work queue" has two bugs for USB drivers.
Firstly, the work queue in question was not initialized. Secondly,
the callback routine used by this queue is contained within the
file used for PCI devices. As a result, it is not available for
architectures without PCI hardware.
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported-by: Richard Genoud <richard.genoud@gmail.com>
Tested-by: Richard Genoud <richard.genoud@gmail.com>
Cc: Richard Genoud <richard.genoud@gmail.com>
Cc: Stable <stable@vger.kernel.org> [3.10]
Signed-off-by: John W. Linville <linville@tuxdriver.com>

When priv_sta == NULL, mi->prev_sample is dereferenced too early. Move
the assignment further down, after the rate_control_send_low call.
Reported-by: Krzysztof Mazur <krzysiek@podlesie.net>
Cc: stable@vger.kernel.org # 3.10
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Bits 1-21 in this channel type attributes are indication for which
SSID is going to be sent on this channel. Since the first SSID is
sent implicitly in the probe request, we don't need to toggle its
bit here.
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Increment index in each iteration. Without this increment we are
overriding the added SSIDs and we will send only the last SSId
and (n_ssids - 1) broadcast probes.

Cc: <stable@vger.kernel.org> [3.9+]
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Due to a firmware bug, it crashes when the beacon interval
is smaller than 16. Avoid this by refusing the station state
change creating the AP station, causing mac80211 to abandon
the attempt to connect to the AP, and eventually wpa_s to
blacklist it.

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

The firmware / HW can't support more than 16 Rx BA sessions.
Deny any attemps to open more sessions than that.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

We didn't release the Rx AMPDU ressources properly.
This bug led to firmware assert after 16 BA sessions.

Cc: <stable@vger.kernel.org> [3.9+]
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

Avoid creating VIF specific debugfs directory if already exist.
This may happen when, for example, resetting hw, suspend-resume.
Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

The BT_CONFIG command that is sent to the device during
startup will enable BT coex unless the module parameter
turns it off, but on devices without Bluetooth this may
cause problems, as reported in Redhat BZ 885407.

Fix this by sending the BT_CONFIG command only when the
device has Bluetooth.

Cc: stable@vger.kernel.org
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

This was missing and prevented any further attempts
to load the module.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

The duplicate retransmission detection code in mac80211
erroneously attempts to do the check for every frame,
even frames that don't have a sequence control field or
that don't use it (QoS-Null frames.)

This is problematic because it causes the code to access
data beyond the end of the SKB and depending on the data
there will drop packets erroneously.

Correct the code to not do duplicate detection for such
frames.

I found this error while testing AP powersave, it lead
to retransmitted PS-Poll frames being dropped entirely
as the data beyond the end of the SKB was always zero.

Cc: stable@vger.kernel.org [all versions]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

RSSI threshold value used for mesh peering should be in
negative value. After range checks to mesh parameters is
introduced, this is not allowed. Fix this.
Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

As reported in https://bugzilla.kernel.org/show_bug.cgi?id=60514,
the station loop never initialises 'sinfo' and therefore adds up
a stack values, leaking stack information (the number of times it
adds values is easily obtained another way.)

Fix this by initialising the sinfo for each station to add.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

The CCK group needs special treatment to set the right flags and rate
index. Add this missing check to prevent setting broken rates for tx
packets.

Cc: stable@vger.kernel.org # 3.10
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

restore_regulatory_settings() requires the RTNL to be held,
add the missing locking in reg_timeout_work().
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When splitting the SME implementation from the MLME code,
I introduced a few bugs:
 * association failures no longer sent a connect-failure event
 * getting disassociated from the AP caused deauth to be sent
   but state wasn't cleaned up, leading to warnings
 * authentication failures weren't cleaned up properly, causing
   new connection attempts to warn and fail

Fix these bugs.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

These two events were sent to the default network
namespace.

This caused AP mode in a non-default netns to not
work correctly. Mgmt tx status was multicasted to
a different (default) netns instead of the one the
AP was in.

Cc: stable@vger.kernel.org
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Pull slab update from Pekka Enberg:
 "Highlights:

  - Fix for boot-time problems on some architectures due to
    init_lock_keys() not respecting kmalloc_caches boundaries
    (Christoph Lameter)

  - CONFIG_SLUB_CPU_PARTIAL requested by RT folks (Joonsoo Kim)

  - Fix for excessive slab freelist draining (Wanpeng Li)

  - SLUB and SLOB cleanups and fixes (various people)"

I ended up editing the branch, and this avoids two commits at the end
that were immediately reverted, and I instead just applied the oneliner
fix in between myself.

* 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux
  slub: Check for page NULL before doing the node_match check
  mm/slab: Give s_next and s_stop slab-specific names
  slob: Check for NULL pointer before calling ctor()
  slub: Make cpu partial slab support configurable
  slab: add kmalloc() to kernel API documentation
  slab: fix init_lock_keys
  slob: use DIV_ROUND_UP where possible
  slub: do not put a slab to cpu partial list when cpu_partial is 0
  mm/slub: Use node_nr_slabs and node_nr_objs in get_slabinfo
  mm/slub: Drop unnecessary nr_partials
  mm/slab: Fix /proc/slabinfo unwriteable for slab
  mm/slab: Sharing s_next and s_stop between slab and slub
  mm/slab: Fix drain freelist excessively
  slob: Rework #ifdeffery in slab.h
  mm, slab: moved kmem_cache_alloc_node comment to correct place

In the -rt kernel (mrg), we hit the following dump:

BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff811573f1>] kmem_cache_alloc_node+0x51/0x180
PGD a2d39067 PUD b1641067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: sunrpc cpufreq_ondemand ipv6 tg3 joydev sg serio_raw pcspkr k8temp amd64_edac_mod edac_core i2c_piix4 e100 mii shpchp ext4 mbcache jbd2 sd_mod crc_t10dif sr_mod cdrom sata_svw ata_generic pata_acpi pata_serverworks radeon ttm drm_kms_helper drm hwmon i2c_algo_bit i2c_core dm_mirror dm_region_hash dm_log dm_mod
CPU 3
Pid: 20878, comm: hackbench Not tainted 3.6.11-rt25.14.el6rt.x86_64 #1 empty empty/Tyan Transport GT24-B3992
RIP: 0010:[<ffffffff811573f1>]  [<ffffffff811573f1>] kmem_cache_alloc_node+0x51/0x180
RSP: 0018:ffff8800a9b17d70  EFLAGS: 00010213
RAX: 0000000000000000 RBX: 0000000001200011 RCX: ffff8800a06d8000
RDX: 0000000004d92a03 RSI: 00000000000000d0 RDI: ffff88013b805500
RBP: ffff8800a9b17dc0 R08: ffff88023fd14d10 R09: ffffffff81041cbd
R10: 00007f4e3f06e9d0 R11: 0000000000000246 R12: ffff88013b805500
R13: ffff8801ff46af40 R14: 0000000000000001 R15: 0000000000000000
FS:  00007f4e3f06e700(0000) GS:ffff88023fd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000000 CR3: 00000000a2d3a000 CR4: 00000000000007e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process hackbench (pid: 20878, threadinfo ffff8800a9b16000, task ffff8800a06d8000)
Stack:
 ffff8800a9b17da0 ffffffff81202e08 ffff8800a9b17de0 000000d001200011
 0000000001200011 0000000001200011 0000000000000000 0000000000000000
 00007f4e3f06e9d0 0000000000000000 ffff8800a9b17e60 ffffffff81041cbd
Call Trace:
 [<ffffffff81202e08>] ? current_has_perm+0x68/0x80
 [<ffffffff81041cbd>] copy_process+0xdd/0x15b0
 [<ffffffff810a2125>] ? rt_up_read+0x25/0x30
 [<ffffffff8104369a>] do_fork+0x5a/0x360
 [<ffffffff8107c66b>] ? migrate_enable+0xeb/0x220
 [<ffffffff8100b068>] sys_clone+0x28/0x30
 [<ffffffff81527423>] stub_clone+0x13/0x20
 [<ffffffff81527152>] ? system_call_fastpath+0x16/0x1b
Code: 89 fc 89 75 cc 41 89 d6 4d 8b 04 24 65 4c 03 04 25 48 ae 00 00 49 8b 50 08 4d 8b 28 49 8b 40 10 4d 85 ed 74 12 41 83 fe ff 74 27 <48> 8b 00 48 c1 e8 3a 41 39 c6 74 1b 8b 75 cc 4c 89 c9 44 89 f2
RIP  [<ffffffff811573f1>] kmem_cache_alloc_node+0x51/0x180
 RSP <ffff8800a9b17d70>
CR2: 0000000000000000
---[ end trace 0000000000000002 ]---

Now, this uses SLUB pretty much unmodified, but as it is the -rt kernel
with CONFIG_PREEMPT_RT set, spinlocks are mutexes, although they do
disable migration. But the SLUB code is relatively lockless, and the
spin_locks there are raw_spin_locks (not converted to mutexes), thus I
believe this bug can happen in mainline without -rt features. The -rt
patch is just good at triggering mainline bugs ;-)

Anyway, looking at where this crashed, it seems that the page variable
can be NULL when passed to the node_match() function (which does not
check if it is NULL). When this happens we get the above panic.

As page is only used in slab_alloc() to check if the node matches, if
it's NULL I'm assuming that we can say it doesn't and call the
__slab_alloc() code. Is this a correct assumption?
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more vfs stuff from Al Viro:
 "O_TMPFILE ABI changes, Oleg's fput() series, misc cleanups, including
  making simple_lookup() usable for filesystems with non-NULL s_d_op,
  which allows us to get rid of quite a bit of ugliness"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  sunrpc: now we can just set ->s_d_op
  cgroup: we can use simple_lookup() now
  efivarfs: we can use simple_lookup() now
  make simple_lookup() usable for filesystems that set ->s_d_op
  configfs: don't open-code d_alloc_name()
  __rpc_lookup_create_exclusive: pass string instead of qstr
  rpc_create_*_dir: don't bother with qstr
  llist: llist_add() can use llist_add_batch()
  llist: fix/simplify llist_add() and llist_add_batch()
  fput: turn "list_head delayed_fput_list" into llist_head
  fs/file_table.c:fput(): add comment
  Safer ABI for O_TMPFILE