Commit Graph

506942 Commits

Author SHA1 Message Date
Luciano Coelho
4500e13376 iwlwifi: mvm: schedule CSA time event a bit before beacon 1
Instead of using a hardcoded number of TUs before beacon 0 as the time
to start the absence and actual channel switch, calculate it in
relation to the beacon interval.  We use 10 TUs + beacon interval
before beacon 0 to target a bit before beacon 1.  This gives us enough
time to switch to the new channel before the AP/GO switches.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:32 +02:00
Luciano Coelho
dc88b4baa9 iwlwifi: mvm: add CSA absent time event for clients
Add an absent time event when pre_channel_switch is called and use the
time event started indication to set the disable_tx bit instead of
doing it in unassign_vif().  This is done so that the firmware queues
are stopped before the actual switch takes place to avoid losing
packets while the AP/GO is performing its actual switch.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:31 +02:00
Luciano Coelho
4741dd049a iwlwifi: mvm: use switching_chanctx argument instead of csa_active
Now that all CSA flows are using the switch_vif_chanctx op, we can
rely on the switching_chanctx boolean that is passed to the
__iwl_mvm_assign_vif_chanctx() and __iwl_mvm_unassign_vif_chanctx()
functions to decide whether the context switch flows need to be
executed.  In this way we make the chanctx switch flow more generic,
without having to rely on the csa_active flag being set.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:30 +02:00
Luciano Coelho
f6c34820d3 iwlwifi: mvm: disable PS during channel switch
Disable PS when pre_channel_switch is called and add the
post_channel_switch operation to re-enable PS when the channel switch
is completed.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:29 +02:00
Andrei Otcheretianski
7ef0aab66b iwlwifi: mvm: Handle failed beacon transmissions during CSA
The spec requires to decrement the CSA counters based on TBTT,
regardless if the beacon was actually transmitted. Previously, the fw
would send beacon notifications only for successfully transmitted
beacons. This behavior resulted in inaccurate CSA countdown. In order
to address this issue, the fw was changed to send beacon
notifications also for not transmitted beacons. Such notifications
have TX_STATUS_INTERNAL_ABORT (0x92).
Don't start the CSA countdown before first successfully transmitted
beacon, in order to guarantee that the CSA is announced for a
required period.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
2014-11-24 08:30:29 +02:00
Luciano Coelho
6fd1fb63ab iwlwifi: mvm: return the actual error code when switch_vif_chanctx fails
We have code to recover and go back to the original channel context if
something fails in the middle of switch_vif_chanctx, but we return the
error code of the recover calls instead of the original code, so if
the recovery succeeds, we will return 0 (success).  Fix this by not
assigning the return value of the recovery calls to ret.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:28 +02:00
Luciano Coelho
48a256e8ae iwlwifi: mvm: add support for CHANCTX_SWMODE_REASSIGN_VIF
Add support to reassign vif in switch_vif_chanctx.  This is similar to
the existing CHANCTX_SWMODE_SWAP_CONTEXTS mode, but doesn't delete the
old context nor creates a new one, doing to switch between two
existing contexts.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:27 +02:00
Luciano Coelho
50cc9574d6 iwlwifi: mvm: refactor iwl_mvm_switch_vif_chanctx to support other modes
Currently we only support the CHANCTX_SWMODE_SWAP_CONTEXTS mode, but
we need to support other modes as well.  Spin a new function off in
order to make it easier to support other modes.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:26 +02:00
Luciano Coelho
6b20d77437 iwlwifi: mvm: only save csa_vif in AP/GO mode
We only need the csa_vif in AP/GO modes, and assigning for other
interfaces may cause problems, because csa_vif is never cleared.  To
prevent this, only assign the value if the iftype is
NL80211_IFTYPE_AP.  Use a switch to do this, even though, for now,
only the AP interface type is handled, because soon other interface
types will be added as well.

Additionally, convert the WARN() in the error case when a
channel-switch is already running to WARN_ONCE().

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:26 +02:00
Luciano Coelho
f028905c20 iwlwifi: mvm: use new pre_channel_switch op instead of channel_switch_beacon
A new callback has been added to prepare the device for a channel
switch.  Use the new callback instead of the old channel_switch_beacon
operation.

This makes it possible to remove the channel_switch_beacon operation
from mac80211.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
2014-11-24 08:30:25 +02:00
Arik Nemtsov
1d3c3f63f7 iwlwifi: mvm: implement mac80211 TDLS channel-switch APIs
Maintain a TDLS channel-switch state and update it according to
notifications from FW and timeouts. Explicitly check all state
transitions are valid.
When switching is initiated by mac80211, use a delayed work to
periodically reschedule it from iwlwifi.
Give the FW mac80211 generated TDLS channel-switch request/response
templates. It will change appropriate values (switch timings) and Tx
them at appropriate times.

Enable the channel switch wiphy capability bit when the FW supports it.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:24 +02:00
Liad Kaufman
9c126cd6e0 iwlwifi: mvm: block TID when using TDLS
Block TID 4 (VI) on a vif when using TDLS. This TID will be used by FW
for TDLS channel-switch requests and PTI requests.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:23 +02:00
Arik Nemtsov
a0f6bf2a5b iwlwifi: mvm: use private TFD queues for TDLS stations
When adding a TDLS station, allocate 4 new queues for it. Configure them
to FW and enable them. On station removal, drain the queues if needed
and disable them when empty.

Make sure to flush all packets in the private queues of TDLS stations in
the mac80211 flush() callback.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:23 +02:00
Arik Nemtsov
cbd2ae2da6 iwlwifi: mvm: disconnect TDLS peers on reconfig
When TDLS peers are present the FW will send packets on a dedicated
TID vs. the peer when performing TDLS channel-switches. The driver
configures the TID on connection to the peer and the FW is responsible
for maintaining the state of QoS seqno and PN/IV for encryption.

If the FW asserts, the driver cannot correctly reconfigure the starting
seqno/PN to the reloaded FW, thus forcing us to reconnect the peer.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:22 +02:00
Arik Nemtsov
a74346d75d iwlwifi: mvm: allow private per-STA TFD queues
TDLS stations will have private queues, so consider them as well when
allocating a new one. Consolidate the HW-queue iterating code into
a single exported function, to be used by the TDLS code in the future.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:21 +02:00
Arik Nemtsov
307e47235a iwlwifi: mvm: configure TDLS peers to FW
Send a dedicated TDLS_CONFIG command when a TDLS peer joins/leaves. The
fields for the command are mostly place-holders, as most of the FW
functionality is not implemented. In the future the dedicated FW TID
will be used for channel-switching and buffer-sta functionality.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:20 +02:00
Arik Nemtsov
77c5d7eff7 iwlwifi: mvm: add TDLS channel switch FW APIs
Add a channel-switch command and a switch-start notification. Also add a
FW TLV bit indicating TDLS channel switching support.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:19 +02:00
Arik Nemtsov
d8f1c51570 iwlwifi: mvm: declare TDLS support
The driver/FW combination now support TDLS.
Check the FW support with the TLV bit.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:19 +02:00
Johannes Berg
3771a89022 iwlwifi: mvm: pull SNAP header into skb->head
When we pre-populate the skb->head for the stack, we only pull
in the 802.11 header including crypto (assuming the packet isn't
short enough to be in there completely.) This is fine, but in
ieee80211_data_to_8023() we later unconditionally pull 8 more
bytes for the SNAP header and ethertype field (except for mesh
or 4-addr, where it's even more, but we don't care as much about
them).

Avoid the additional later pull by pulling in those 8 bytes here.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: IdoX Yariv <ido@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:18 +02:00
Johannes Berg
eb96ccb138 iwlwifi: mvm: pull crypto header into skb->head
When we pre-populate the skb->head for the stack, we only pull
in the 802.11 header (assuming the packet isn't short enough to
be in there completely.) This is fine, but in many cases we'll
pull in the crypto headers pretty much immediately afterwards,
so to avoid that pull in the crypto header early.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: IdoX Yariv <ido@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:17 +02:00
Johannes Berg
d0963b5d31 iwlwifi: build mac80211 rx_status in place
Instead of building the rx_status on the stack and then
copying it to the skb, allocate the skb a bit earlier
and then build the rx_status in place.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: IdoX Yariv <ido@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:16 +02:00
Johannes Berg
ba3943b094 iwlwifi: mvm: add WEP RX hardware offload support
In the original driver, we decided to not implement WEP RX hardware
offload because of a quirk with the firmware API - it allows setting
global WEP keys that then get used for all virtual interfaces, which
is clearly wrong if more than one exists, and it allows setting per-
station keys but then separates multicast and unicast keys.

In order to implement WEP RX hardware offload, work around these
limitations by uploading each WEP key twice, once as multicast and
once as unicast, but point them both to the same key slot (offset)
and use the same key material so the slot overwrite on the second
upload doesn't actually change anything. Upon removal, also remove
the key twice so the station no longer references it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:16 +02:00
Johannes Berg
2f6319d1cf iwlwifi: mvm: refactor key add/remove functions
Refactor the key add/remove functions to be able to reuse parts
of them later for RX WEP keys, which need to be uploaded twice.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:15 +02:00
Matti Gottlieb
bf5da87f60 iwlwifi: mvm: add remove flow for AUX ROC time events
Add a flow that handles the requests to cancel the roc time event,
that has been triggered via the aux framework.

The roc for bss is different than the roc for p2p devices, and  is done
via the aux framework using the aux queue, thus requires a different flow
to cancel the time event.

Signed-off-by: Matti Gottlieb <matti.gottlieb@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:14 +02:00
David Spinadel
2992a324e3 iwlwifi: mvm: remove warning on unknown scan complete
Remove warning on scan complete with unknown ID, since this
scan could be already cleared in abort flow.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:13 +02:00
Johannes Berg
c8660dd5e9 iwlwifi: mvm: use unsigned for ssid_bitmap
The ssid_bitmap should be unsigned, though it doesn't matter
much as the high bits aren't used.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:13 +02:00
Johannes Berg
3fd0d3c170 iwlwifi: pcie: support 7265-D devices
Identify 7265-D devices using the hardware revision (they have the
same PCI IDs as 7265) and change the configuration for them taking
the differences (currently only the firmware image) into account.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-11-24 08:30:12 +02:00
Jaegeuk Kim
0341845efc f2fs: fix livelock calling f2fs_iget during f2fs_evict_inode
In f2fs_evict_inode,
 commit_inmemory_pages
   f2fs_gc
     f2fs_iget
       iget_locked
         -> wait for inode free

Here, if the inode is same as the one to be evicted, f2fs should wait forever.
Actually, we should not call f2fs_balance_fs during f2fs_evict_inode to avoid
this.

But, the commit_inmem_pages calls f2fs_balance_fs by default, even if
f2fs_evict_inode wants to free inmemory pages only.

Hence, this patch adds to trigger f2fs_balance_fs only when there is something
to write.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23 21:51:57 -08:00
Jaegeuk Kim
9486ba442b f2fs: introduce f2fs_dentry_kunmap to clean up
This patch introduces f2fs_dentry_kunmap to clean up dirty codes.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23 21:51:53 -08:00
Changman Lee
c9ee00857c f2fs: fix wrong data structure when create slab
It used nat_entry_set when create slab for sit_entry_set.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23 21:48:49 -08:00
Jaegeuk Kim
09b8b3c839 f2fs: call flush_dcache_page when the page was updated
Whenever f2fs updates mapped pages, it needs to call flush_dcache_page.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23 21:48:31 -08:00
Benjamin Herrenschmidt
31345e1a07 powerpc/pci: Remove unused force_32bit_msi quirk
This is now fully replaced with the generic "no_64bit_msi" one
that is set by the respective drivers directly.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-11-24 14:36:02 +11:00
Benjamin Herrenschmidt
415072a041 powerpc/pseries: Honor the generic "no_64bit_msi" flag
Instead of the arch specific quirk which we are deprecating

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
2014-11-24 14:36:02 +11:00
Benjamin Herrenschmidt
360743814c powerpc/powernv: Honor the generic "no_64bit_msi" flag
Instead of the arch specific quirk which we are deprecating
and that drivers don't understand.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
2014-11-24 14:36:01 +11:00
Benjamin Herrenschmidt
db79afa1e5 sound/radeon: Move 64-bit MSI quirk from arch to driver
A number of radeon cards have a HW limitation causing them to be
unable to generate the full 64-bit of address bits for MSIs. This
breaks MSIs on some platforms such as POWER machines.

We used to have a powerpc specific quirk to address that on a
single card, but this doesn't scale very well, this is better
put under control of the drivers who know precisely what a given
HW revision can do.

We now have a generic quirk in the PCI code. We should set it
appropriately for all radeon's from the audio driver.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
CC: <stable@vger.kernel.org>
2014-11-24 14:17:34 +11:00
Benjamin Herrenschmidt
91ed6fd2c3 gpu/radeon: Set flag to indicate broken 64-bit MSI
Some radeon ASICs don't support all 64 address bits of MSIs despite
advertising support for 64-bit MSIs in their configuration space.

This breaks on systems such as IBM POWER7/8, where 64-bit MSIs can
be assigned with some of the high address bits set.

This makes use of the newly introduced "no_64bit_msi" flag in structure
pci_dev to allow the MSI allocation code to fallback to 32-bit MSIs
on those adapters.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
CC: <stable@vger.kernel.org>
---

Adding Alex's review tag. Patch to the driver is identical to the
reviewed one, I dropped the arch/powerpc hunk rewrote the subject
and cset comment.
2014-11-24 14:12:56 +11:00
Benjamin Herrenschmidt
f144d1496b PCI/MSI: Add device flag indicating that 64-bit MSIs don't work
This can be set by quirks/drivers to be used by the architecture code
that assigns the MSI addresses.

We additionally add verification in the core MSI code that the values
assigned by the architecture do satisfy the limitation in order to fail
gracefully if they don't (ie. the arch hasn't been updated to deal with
that quirk yet).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2014-11-24 14:11:34 +11:00
Takashi Iwai
413cbf469a ALSA: hda - Limit 40bit DMA for AMD HDMI controllers
AMD/ATI HDMI controller chip models, we already have a filter to lower
to 32bit DMA, but the rest are supposed to be working with 64bit
although the hardware doesn't really work with 63bit but only with 40
or 48bit DMA.  In this patch, we take 40bit DMA for safety for the
AMD/ATI controllers as the graphics drivers does.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
2014-11-24 14:02:53 +11:00
lucien
20ea60ca99 ip_tunnel: the lack of vti_link_ops' dellink() cause kernel panic
Now the vti_link_ops do not point the .dellink, for fb tunnel device
(ip_vti0), the net_device will be removed as the default .dellink is
unregister_netdevice_queue,but the tunnel still in the tunnel list,
then if we add a new vti tunnel, in ip_tunnel_find():

        hlist_for_each_entry_rcu(t, head, hash_node) {
                if (local == t->parms.iph.saddr &&
                    remote == t->parms.iph.daddr &&
                    link == t->parms.link &&
==>                 type == t->dev->type &&
                    ip_tunnel_key_match(&t->parms, flags, key))
                        break;
        }

the panic will happen, cause dev of ip_tunnel *t is null:
[ 3835.072977] IP: [<ffffffffa04103fd>] ip_tunnel_find+0x9d/0xc0 [ip_tunnel]
[ 3835.073008] PGD b2c21067 PUD b7277067 PMD 0
[ 3835.073008] Oops: 0000 [#1] SMP
.....
[ 3835.073008] Stack:
[ 3835.073008]  ffff8800b72d77f0 ffffffffa0411924 ffff8800bb956000 ffff8800b72d78e0
[ 3835.073008]  ffff8800b72d78a0 0000000000000000 ffffffffa040d100 ffff8800b72d7858
[ 3835.073008]  ffffffffa040b2e3 0000000000000000 0000000000000000 0000000000000000
[ 3835.073008] Call Trace:
[ 3835.073008]  [<ffffffffa0411924>] ip_tunnel_newlink+0x64/0x160 [ip_tunnel]
[ 3835.073008]  [<ffffffffa040b2e3>] vti_newlink+0x43/0x70 [ip_vti]
[ 3835.073008]  [<ffffffff8150d4da>] rtnl_newlink+0x4fa/0x5f0
[ 3835.073008]  [<ffffffff812f68bb>] ? nla_strlcpy+0x5b/0x70
[ 3835.073008]  [<ffffffff81508fb0>] ? rtnl_link_ops_get+0x40/0x60
[ 3835.073008]  [<ffffffff8150d11f>] ? rtnl_newlink+0x13f/0x5f0
[ 3835.073008]  [<ffffffff81509cf4>] rtnetlink_rcv_msg+0xa4/0x270
[ 3835.073008]  [<ffffffff8126adf5>] ? sock_has_perm+0x75/0x90
[ 3835.073008]  [<ffffffff81509c50>] ? rtnetlink_rcv+0x30/0x30
[ 3835.073008]  [<ffffffff81529e39>] netlink_rcv_skb+0xa9/0xc0
[ 3835.073008]  [<ffffffff81509c48>] rtnetlink_rcv+0x28/0x30
....

modprobe ip_vti
ip link del ip_vti0 type vti
ip link add ip_vti0 type vti
rmmod ip_vti

do that one or more times, kernel will panic.

fix it by assigning ip_tunnel_dellink to vti_link_ops' dellink, in
which we skip the unregister of fb tunnel device. do the same on ip6_vti.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-23 21:11:17 -05:00
Eric Dumazet
c33d23c215 enic: use netdev_rss_key_fill() helper
Use of well known RSS key might increase attack surface.

Switch to a random one, using generic helper so that all
ports share a common key.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Christian Benvenuti <benve@cisco.com>
Cc: Govindarajulu Varadarajan <_govind@gmx.com>
Cc: Sujith Sankar <ssujith@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-23 21:01:42 -05:00
Ian Morris
e5d08d718a ipv6: coding style improvements (remove assignment in if statements)
This change has no functional impact and simply addresses some coding
style issues detected by checkpatch. Specifically this change
adjusts "if" statements which also include the assignment of a
variable.

No changes to the resultant object files result as determined by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-23 21:00:56 -05:00
Eric Dumazet
a12f5d48bd dm: use rcu_dereference_protected instead of rcu_dereference
rcu_dereference() should be used in sections protected by rcu_read_lock.

For writers, holding some kind of mutex or lock,
rcu_dereference_protected() is the way to go, adding explicit lockdep
bits.

In __unbind(), we are the last user of this mapped device, so can use
the constant '1' instead of a lockdep_is_held(), not consistent with
other uses of rcu_dereference_protected() which use md->suspend_lock
mutex.

Reported-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 33423974bf ("dm: Use rcu_dereference() for accessing rcu pointer")
Cc: Pranith Kumar <bobby.prani@gmail.com>
[snitzer: allow lines longer than 80 columns, refine subject]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-23 20:32:45 -05:00
Lan Tianyu
40e7fcb192 ACPI: Add _DEP support to fix battery issue on Asus T100TA
ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate
device objects that OSPM should assign a higher priority in start
ordering due to future operation region accesses.

On Asus T100TA, ACPI battery info are read from a I2C slave device via
I2C operation region. Before I2C operation region handler is installed,
battery _STA always returns 0. There is a _DEP method of designating
start order under battery device node.

This patch is to implement _DEP feature to fix battery issue on the
Asus T100TA.  Introducing acpi_dep_list and adding dep_unmet count
in struct acpi_device. During ACPI namespace scan, create struct
acpi_dep_data for a valid pair of master (device pointed to by _DEP)/
slave(device with _DEP), record master's and slave's ACPI handle in
it and put it into acpi_dep_list. The dep_unmet count will increase
by one if there is a device under its _DEP. Driver's probe() should
return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C
operation region handler is installed, remove all struct acpi_dep_data
on the acpi_dep_list whose master is pointed to I2C host controller
and decrease slave's dep_unmet. When dep_unmet decreases to 0, all
_DEP conditions are met and then do acpi_bus_attach() for the device
in order to resolve battery _STA issue on the Asus T100TA.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011
Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org>
Tested-by: Adam Williamson <adamw@happyassassin.net>
Tested-by: Michael Shigorin <shigorin@gmail.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-24 01:04:55 +01:00
Linus Torvalds
5d01410fe4 Linux 3.18-rc6 v3.18-rc6 2014-11-23 15:25:20 -08:00
Andy Lutomirski
82975bc6a6 uprobes, x86: Fix _TIF_UPROBE vs _TIF_NOTIFY_RESUME
x86 call do_notify_resume on paranoid returns if TIF_UPROBE is set but
not on non-paranoid returns.  I suspect that this is a mistake and that
the code only works because int3 is paranoid.

Setting _TIF_NOTIFY_RESUME in the uprobe code was probably a workaround
for the x86 bug.  With that bug fixed, we can remove _TIF_NOTIFY_RESUME
from the uprobes code.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-23 14:25:28 -08:00
Thomas Gleixner
90e362f4a7 sched: Provide update_curr callbacks for stop/idle scheduling classes
Chris bisected a NULL pointer deference in task_sched_runtime() to
commit 6e998916df 'sched/cputime: Fix clock_nanosleep()/clock_gettime()
inconsistency'.

Chris observed crashes in atop or other /proc walking programs when he
started fork bombs on his machine.  He assumed that this is a new exit
race, but that does not make any sense when looking at that commit.

What's interesting is that, the commit provides update_curr callbacks
for all scheduling classes except stop_task and idle_task.

While nothing can ever hit that via the clock_nanosleep() and
clock_gettime() interfaces, which have been the target of the commit in
question, the author obviously forgot that there are other code paths
which invoke task_sched_runtime()

do_task_stat(()
 thread_group_cputime_adjusted()
   thread_group_cputime()
     task_cputime()
       task_sched_runtime()
        if (task_current(rq, p) && task_on_rq_queued(p)) {
          update_rq_clock(rq);
          up->sched_class->update_curr(rq);
        }

If the stats are read for a stomp machine task, aka 'migration/N' and
that task is current on its cpu, this will happily call the NULL pointer
of stop_task->update_curr.  Ooops.

Chris observation that this happens faster when he runs the fork bomb
makes sense as the fork bomb will kick migration threads more often so
the probability to hit the issue will increase.

Add the missing update_curr callbacks to the scheduler classes stop_task
and idle_task.  While idle tasks cannot be monitored via /proc we have
other means to hit the idle case.

Fixes: 6e998916df 'sched/cputime: Fix clock_nanosleep()/clock_gettime() inconsistency'
Reported-by: Chris Mason <clm@fb.com>
Reported-and-tested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-23 14:14:40 -08:00
Linus Torvalds
00c89b2f11 Merge branch 'x86-traps' (trap handling from Andy Lutomirski)
Merge x86-64 iret fixes from Andy Lutomirski:
 "This addresses the following issues:

   - an unrecoverable double-fault triggerable with modify_ldt.
   - invalid stack usage in espfix64 failed IRET recovery from IST
     context.
   - invalid stack usage in non-espfix64 failed IRET recovery from IST
     context.

  It also makes a good but IMO scary change: non-espfix64 failed IRET
  will now report the correct error.  Hopefully nothing depended on the
  old incorrect behavior, but maybe Wine will get confused in some
  obscure corner case"

* emailed patches from Andy Lutomirski <luto@amacapital.net>:
  x86_64, traps: Rework bad_iret
  x86_64, traps: Stop using IST for #SS
  x86_64, traps: Fix the espfix64 #DF fixup and rewrite it in C
2014-11-23 13:56:55 -08:00
Andy Lutomirski
b645af2d59 x86_64, traps: Rework bad_iret
It's possible for iretq to userspace to fail.  This can happen because
of a bad CS, SS, or RIP.

Historically, we've handled it by fixing up an exception from iretq to
land at bad_iret, which pretends that the failed iret frame was really
the hardware part of #GP(0) from userspace.  To make this work, there's
an extra fixup to fudge the gs base into a usable state.

This is suboptimal because it loses the original exception.  It's also
buggy because there's no guarantee that we were on the kernel stack to
begin with.  For example, if the failing iret happened on return from an
NMI, then we'll end up executing general_protection on the NMI stack.
This is bad for several reasons, the most immediate of which is that
general_protection, as a non-paranoid idtentry, will try to deliver
signals and/or schedule from the wrong stack.

This patch throws out bad_iret entirely.  As a replacement, it augments
the existing swapgs fudge into a full-blown iret fixup, mostly written
in C.  It's should be clearer and more correct.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-23 13:56:19 -08:00
Andy Lutomirski
6f442be2fb x86_64, traps: Stop using IST for #SS
On a 32-bit kernel, this has no effect, since there are no IST stacks.

On a 64-bit kernel, #SS can only happen in user code, on a failed iret
to user space, a canonical violation on access via RSP or RBP, or a
genuine stack segment violation in 32-bit kernel code.  The first two
cases don't need IST, and the latter two cases are unlikely fatal bugs,
and promoting them to double faults would be fine.

This fixes a bug in which the espfix64 code mishandles a stack segment
violation.

This saves 4k of memory per CPU and a tiny bit of code.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-23 13:56:19 -08:00
Andy Lutomirski
af726f21ed x86_64, traps: Fix the espfix64 #DF fixup and rewrite it in C
There's nothing special enough about the espfix64 double fault fixup to
justify writing it in assembly.  Move it to C.

This also fixes a bug: if the double fault came from an IST stack, the
old asm code would return to a partially uninitialized stack frame.

Fixes: 3891a04aaf
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-11-23 13:56:18 -08:00