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Use the new extended capabilities advertising to advertise
the fact that operating mode notification is supported.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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In many cases, userspace may need to know which of the
802.11 extended capabilities ("Extended Capabilities
element") are implemented in the driver or device, to
include them e.g. in beacons, assoc request/response
or other frames. Add a new nl80211 attribute to hold
the extended capabilities bitmap for this.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Instead of modifying the HT SMPS capability field
for stations, track the SMPS mode explicitly in a
new field in the station struct and use it in the
drivers that care about it. This simplifies the
code using it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Mesh interfaces will now respond to any broadcast (or
matching directed mesh) probe requests with a probe
response.
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Previously, the entire mesh beacon would be generated each
time the beacon timer fired. Instead generate a beacon
head and tail (so the TIM can easily be inserted when mesh
power save is on) when starting a mesh or the MBSS
parameters change.
Also add a mutex for protecting beacon updates and
preventing leaks.
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Make all the parsed IE pointers const, and propagate
the change to all the users etc.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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When drivers or regulatory have limitations on
40, 80 or 160 MHz channels, advertise these to
userspace via nl80211. Also add a new feature
flag to let userspace know this is supported.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Some drivers might support 80 or 160 MHz only on some
channels for whatever reason, so allow them to disable
these channel widths. Also maintain the new flags when
regulatory bandwidth limitations would disable these
wide channels.
Reviewed-by: Luis R. Rodriguez <mcgrof@do-not-panic.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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A while ago, I made the mac80211 station code never change
the channel type after association. This solved a number of
issues but is ultimately wrong, we should react if the AP
changes the HT operation IE and switches bandwidth. One of
the issues is that we associate as HT40 capable, but if the
AP ever switches to 40 MHz we won't be able to receive such
frames because we never set our channel to 40 MHz.
This addresses this and VHT operation changes. If there's a
change that is incompatible with our setup, e.g. if the AP
decides to change the channel entirely (and for some reason
we still hear the beacon) we'll just disconnect.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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The next patch will need it further up in the file, so
move it unchanged now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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For HT and VHT the current bandwidth can change,
add the function ieee80211_vif_change_bandwidth()
to take care of this. It returns a failure if the
new bandwidth isn't compatible with the existing
channel context, the caller has to handle that.
When it happens, also inform the driver that the
bandwidth changed for this virtual interface (no
drivers would actually care today though.)
Changing to/from HT/VHT isn't allowed though.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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The channel use is confusing, some uses the channel
context and some the bss_conf.chandef. The latter is
fine, so get rid of the channel context part.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Having HT/VHT operation IEs but not capability IEs
leads to a strange situation where we configure the
channel to an HT or VHT bandwidth and then can't
actually use it. Prevent this by checking that the
HT and VHT capability IEs are present as well as
the operation IEs; if not, disable HT and/or VHT.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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In beacons and association response frames an AP may include an
operating mode notification element to advertise changes in the
number of spatial streams it can receive. Handle this using the
existing function that handles the action frame, but only handle
NSS changes, not bandwidth changes which aren't allowed here.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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This should be called ieee80211_change_chanctx() since
it changes the channel context, not a chandef.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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The code to disable HT and VHT if VHT was advertised
without VHT is wrong -- it accidentally uses the wrong
flags. Fix that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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In case of connection, the station data is initialised from
the beacon/probe response first and then updated from the
association response. If the latter is different we update
the rate control algorithm and driver. Instead of doing it
this way, set the station data properly with data from the
association response before initializing rate control.
Also simplify the code by passing the station pointer.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Handle the operating mode notification action frame.
When the supported streams or the bandwidth change
let the driver and rate control algorithm know.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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With VHT, a station can change the number of spatial
streams it can receive on the fly, not unlike spatial
multiplexing in HT. Prepare for that by tracking the
maximum number of spatial streams it can receive when
the connection is established.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Define the action frame format, the VHT category
and its action types and the field format and EID
for operating mode notifications. The frame may
be used outside of VHT context as well, so don't
include "VHT" in the names.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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For VHT, many more bandwidth changes are possible. As a first
step, stop toggling the IEEE80211_HT_CAP_SUP_WIDTH_20_40 flag
in the HT capabilities and instead introduce a bandwidth field
indicating the currently usable bandwidth to transmit to the
station. Of course, make all drivers use it.
To achieve this, make ieee80211_ht_cap_ie_to_sta_ht_cap() get
the station as an argument, rather than the new capabilities,
so it can set up the new bandwidth field.
If the station is a VHT station and VHT bandwidth is in use,
also set the bandwidth accordingly.
Doing this allows us to get rid of the supports_40mhz flag as
the HT capabilities now reflect the true capability instead of
the current setting.
While at it, also fix ieee80211_ht_cap_ie_to_sta_ht_cap() to not
ignore HT cap overrides when MCS TX isn't supported (not that it
really happens...)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Like with HT, make things a bit simpler in future patches by
passing the station to ieee80211_vht_cap_ie_to_sta_vht_cap()
instead of the vht_cap pointer. Also disable VHT here if HT
isn't supported.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Since no driver calls the TKIP functions from interrupt
context, there's no need to use spin_lock_irqsave().
Just use spin_lock_bh() (and spin_lock() in the TX path
where we're in a BH or they're already disabled.)
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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There's no need to use _irqsave() as the lock
is never used in interrupt context.
This also fixes a problem in the iwlwifi MVM
driver that calls spin_unlock_bh() within its
set_tim() callback.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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There's no use for it, WPA is entirely handled in
wpa_supplicant in userspace, so don't pick the IE.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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In some cases when disconnecting after (or during?) CSA
the queues might not recover, and then the only way to
recover is reloading the module.
Fix this by always unblocking the queue CSA reason when
disconnecting.
Cc: stable@vger.kernel.org
Reported-by: Jan-Michael Brummer <jan.brummer@tabos.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Since the idle decision rework, mac80211 started calling
bss_info_changed() for the driver's monitor interface,
which causes a crash for iwlwifi, but drivers generally
don't expect this to happen. Therefore, avoid it.
While at it, also prevent calling it in such cases and
only print a warning. For the P2P Device interface the
idle will no longer be called (no channel context), so
also prevent that and warn on it.
Reported-by: Chaitanya <chaitanya.mgit@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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In my commit 1672c0e31917f49d31d30d79067103432bc20cc7
("mac80211: start auth/assoc timeout on frame status")
I broke auth/assoc timeout handling: in case we wait
for the TX status, it now leaves the timeout field set
to 0, which is a valid time and can compare as being
before now ("jiffies"). Thus, if the work struct runs
for some other reason, the auth/assoc is treated as
having timed out.
Fix this by introducing a separate "timeout_started"
variable that tracks whether the timeout has started
and is checked before timing out.
Additionally, for proper TX status handling the change
requires that the skb->dev pointer is set up for all
the frames, so set it up for all frames in mac80211.
Reported-by: Wojciech Dubowik <Wojciech.Dubowik@neratec.com>
Tested-by: Wojciech Dubowik <Wojciech.Dubowik@neratec.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Function ieee80211_sta_reset_conn_monitor has been
resetting probe_send_count too early and nullfunc
check was never called after succesfull ack.
Reported-by: Magnus Cederlöf <mcider@gmail.com>
Tested-by: Magnus Cederlöf <mcider@gmail.com>
Signed-off-by: Wojciech Dubowik <Wojciech.Dubowik@neratec.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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A few mesh utility functions will call
ieee80211_bss_info_change_notify(), and then the caller
might notify the driver of the same change again. Avoid
this redundancy by propagating the BSS changes and
generally calling bss_info_change_notify() once per
change.
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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When sending a broadcast while at least on of the connected stations is
sleeping, it gets queued and send after a DTIM beacon is sent.
If the packet was to be sent on a vlan interface, the vif used for dequeing
from the per-bss queue does not hold the per-vlan sdata. The correct sdata is
required to use the correct per-vlan broadcast/multicast key.
This patch fixes this by restoring the per-vlan sdata using the skb->dev entry.
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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When the vlan device is removed, ps->bc_buf processing can no longer
send its frames.
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Add command to trigger radar detection in the driver/FW.
Once radar detection is started it should continuously
monitor for radars as long as the channel active.
If radar is detected usermode notified with 'radar
detected' event.
Scanning and remain on channel functionality must be disabled
while doing radar detection/scanning, and vice versa.
Based on original patch by Victor Goldenshtein <victorg@ti.com>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Add new NL80211_CMD_RADAR_DETECT, which starts the Channel
Availability Check (CAC). This command will also notify the
usermode about events (CAC finished, CAC aborted, radar
detected, NOP finished).
Once radar detection has started it should continuously
monitor for radars as long as the channel is active.
This patch enables DFS for AP mode in nl80211/cfg80211.
Based on original patch by Victor Goldenshtein <victorg@ti.com>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
[remove WIPHY_FLAG_HAS_RADAR_DETECT again -- my mistake]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
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Patch 85a18198 "clk: sunxi: Use common of_clk_init() function"
removed the clk-sunxi.c file but left the Makefile entry, which
causes a build error in multi_v7_defconfig:
make[4]: *** No rule to make target `drivers/clk/clk-sunxi.o', needed by `drivers/clk/built-in.o'.
The obvious fix is to remove the extraneous line from the
Makefile.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Prashant Gaikwad <pgaikwad@nvidia.com>
Cc: Maxime Ripard <maxime.ripard@anandra.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
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This reverts commit 9d02b43dee0d7fb18dfb13a00915550b1a3daa9f.
We are doing this b/c on 32-bit PVonHVM with older hypervisors
(Xen 4.1) it ends up bothing up the start_info. This is bad b/c
we use it for the time keeping, and the timekeeping code loops
forever - as the version field never changes. Olaf says to
revert it, so lets do that.
Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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This reverts commit a7be94ac8d69c037d08f0fd94b45a593f1d45176.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Fix kconfig warning for LGUEST_GUEST config by selecting TTY:
warning: (KVMTOOL_TEST_ENABLE && LGUEST_GUEST) selects VIRTIO_CONSOLE which has unmet direct dependencies (VIRTIO && TTY)
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Joe Millenbach <jmillenbach@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When we are converting local data to an extent format as a result of
adding an attribute, the type of data contained in the local fork
determines the behaviour that needs to occur.
xfs_bmap_add_attrfork_local() already handles the directory data
case specially by using S_ISDIR() and calling out to
xfs_dir2_sf_to_block(), but with verifiers we now need to handle
each different type of metadata specially and different metadata
formats require different verifiers (and eventually block header
initialisation).
There is only a single place that we add and attribute fork to
the inode, but that is in the attribute code and it knows nothing
about the specific contents of the data fork. It is only the case of
local data that is the issue here, so adding code to hadnle this
case in the attribute specific code is wrong. Hence we are really
stuck trying to detect the data fork contents in
xfs_bmap_add_attrfork_local() and performing the correct callout
there.
Luckily the current cases can be determined by S_IS* macros, and we
can push the work off to data specific callouts, but each of those
callouts does a lot of work in common with
xfs_bmap_local_to_extents(). The only reason that this fails for
symlinks right now is is that xfs_bmap_local_to_extents() assumes
the data fork contains extent data, and so attaches a a bmap extent
data verifier to the buffer and simply copies the data fork
information straight into it.
To fix this, allow us to pass a "formatting" callback into
xfs_bmap_local_to_extents() which is responsible for setting the
buffer type, initialising it and copying the data fork contents over
to the new buffer. This allows callers to specify how they want to
format the new buffer (which is necessary for the upcoming CRC
enabled metadata blocks) and hence make xfs_bmap_local_to_extents()
useful for any type of data fork content.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
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The trylock log force invoked via xfs_buf_item_push() can attempt
to acquire xa_lock, thus leading to a recursion bug when called
with xa_lock held.
This log force was originally added to xfs_buf_trylock() to address
xfsaild stalls due to pinned and stale buffers. Since the addition
of this behavior, the log item pushing code had been reworked to
detect and track pinned items to inform xfsaild to issue a log
force itself when necessary. As such, the log force on trylock
failure is redundant and safe to remove.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
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The buffer pinned check and trylock sequence in xfs_buf_item_push()
can race with an active transaction on marking the buffer pinned.
This can result in the buffer becoming pinned and stale after the
initial check and the trylock failure, but before the check in
xfs_buf_trylock() that issues a log force. If the log force is
issued from this context, a spinlock recursion occurs on xa_lock.
Prepare xfs_buf_item_push() to handle the race by detecting a
pinned buffer after the trylock failure so xfsaild issues a log
force from a safe context. This, along with various previous fixes,
renders the log force in xfs_buf_trylock() redundant.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
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Speculative preallocation based on the current file size works well
for contiguous files, but is sub-optimal for sparse files where the
EOF preallocation can fill holes and result in large amounts of
zeros being written when it is not necessary.
The algorithm is modified to prevent EOF speculative preallocation
from triggering larger allocations on IO patterns of
truncate--to-zero-seek-write-seek-write-.... which results in
non-sparse files for large files. This, unfortunately, is the way cp
now behaves when copying sparse files and so needs to be fixed.
What this code does is that it looks at the existing extent adjacent
to the current EOF and if it determines that it is a hole we disable
speculative preallocation altogether. To avoid the next write from
doing a large prealloc, it takes the size of subsequent
preallocations from the current size of the existing EOF extent.
IOWs, if you leave a hole in the file, it resets preallocation
behaviour to the same as if it was a zero size file.
Example new behaviour:
$ xfs_io -f -c "pwrite 0 31m" \
-c "pwrite 33m 1m" \
-c "pwrite 128m 1m" \
-c "fiemap -v" /mnt/scratch/blah
wrote 32505856/32505856 bytes at offset 0
31 MiB, 7936 ops; 0.0000 sec (1.608 GiB/sec and 421432.7439 ops/sec)
wrote 1048576/1048576 bytes at offset 34603008
1 MiB, 256 ops; 0.0000 sec (1.462 GiB/sec and 383233.5329 ops/sec)
wrote 1048576/1048576 bytes at offset 134217728
1 MiB, 256 ops; 0.0000 sec (1.719 GiB/sec and 450704.2254 ops/sec)
/mnt/scratch/blah:
EXT: FILE-OFFSET BLOCK-RANGE TOTAL FLAGS
0: [0..65535]: 96..65631 65536 0x0
1: [65536..67583]: hole 2048
2: [67584..69631]: 67680..69727 2048 0x0
3: [69632..262143]: hole 192512
4: [262144..264191]: 262240..264287 2048 0x1
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
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Move the reservation of low memory, except for the 4K which actually
does belong to the BIOS, later in the initialization; in particular,
after we have already reserved the trampoline.
The current code locates the trampoline as high as possible, so by
deferring the allocation we will still be able to reserve as much
memory as is possible. This allows us to run with reservelow=640k
without getting a crash on system startup.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-0y9dqmmsousf69wutxwl3kkf@git.kernel.org
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Patch 16559ae "kgdb: remove #include <linux/serial_8250.h> from kgdb.h"
removed an implicit inclusion of linux/platform_device.h
In a number of places. This adds back explicit inclusions in a few
more places I found.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Patch 16559ae "kgdb: remove #include <linux/serial_8250.h> from kgdb.h"
removed an implicit inclusion of linux/platform_device.h
from the exynos framebuffer driver. This adds back the required
explicit header file inclusions.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ajay Kumar <ajaykumar.rs@samsung.com>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Patch "16559ae kgdb: remove #include <linux/serial_8250.h> from kgdb.h
caused assabet_defconfig to fail, since assabet.c did not
itself include linux/platform_device.h, although it needs it:
In file included from include/linux/mfd/ucb1x00.h:13:0,
from arch/arm/mach-sa1100/assabet.c:19:
include/linux/mfd/mcp.h:22:16: error: field 'attached_device' has incomplete type
include/linux/mfd/mcp.h:48:23: error: field 'drv' has incomplete type
In file included from arch/arm/mach-sa1100/assabet.c:19:0:
include/linux/mfd/ucb1x00.h:137:16: error: field 'dev' has incomplete type
arch/arm/mach-sa1100/assabet.c: In function 'assabet_init':
arch/arm/mach-sa1100/assabet.c:343:3: error: implicit declaration of function 'platform_device_register_simple' [-Wimplicit-function-declaration]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Even for non-pfmalloc SKBs, __netif_receive_skb() will do a
tsk_restore_flags() on current unconditionally.
Make __netif_receive_skb() a shim around the existing code, renamed to
__netif_receive_skb_core(). Let __netif_receive_skb() wrap the
__netif_receive_skb_core() call with the task flag modifications, if
necessary.
Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit cb57a2b4cff7edf2a4e32c0163200e9434807e0a ("x86-32: Export
kernel_stack_pointer() for modules") added an include of the
module.h header in conjunction with adding an EXPORT_SYMBOL_GPL
of kernel_stack_pointer.
But module.h should be avoided for simple exports, since it in turn
includes the world. Swap the module.h for export.h instead.
Cc: Jiri Kosina <trivial@kernel.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: http://lkml.kernel.org/r/1360872842-28417-1-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
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commit 9ec1882df2 (tty: serial: imx: console write routing is unsafe
on SMP) introduced a recursive locking bug in imx_console_write().
The callchain is:
imx_rxint()
spin_lock_irqsave(&sport->port.lock,flags);
...
uart_handle_sysrq_char();
sysrq_function();
printk();
imx_console_write();
spin_lock_irqsave(&sport->port.lock,flags); <--- DEAD
The bad news is that the kernel debugging facilities can dectect the
problem, but the printks never surface on the serial console for
obvious reasons.
There is a similar issue with oops_in_progress. If the kernel crashes
we really don't want to be stuck on the lock and unable to tell what
happened.
In general most UP originated drivers miss these checks and nobody
ever notices because CONFIG_PROVE_LOCKING seems to be still ignored by
a large number of developers.
The solution is to avoid locking in the sysrq case and trylock in the
oops_in_progress case.
This scheme is used in other drivers as well and it would be nice if
we could move this to a common place, so the usual copy/paste/modify
bugs can be avoided.
Now there is another issue with this scheme:
CPU0 CPU1
printk()
rxint()
sysrq_detection() -> sets port->sysrq
return from interrupt
console_write()
if (port->sysrq)
avoid locking
port->sysrq is reset with the next receive character. So as long as
the port->sysrq is not reset and this can take an endless amount of
time if after the break no futher receive character follows, all
console writes happen unlocked.
While the current writer is protected against other console writers by
the console sem, it's unprotected against open/close or other
operations which fiddle with the port. That's what the above mentioned
commit tried to solve.
That's an issue in all drivers which use that scheme and unfortunately
there is no easy workaround. The only solution is to have a separate
indicator port->sysrq_cpu. uart_handle_sysrq_char() then sets it to
smp_processor_id() before calling into handle_sysrq() and resets it to
-1 after that. Then change the locking check to:
if (port->sysrq_cpu == smp_processor_id())
locked = 0;
else if (oops_in_progress)
locked = spin_trylock_irqsave(port->lock, flags);
else
spin_lock_irqsave(port->lock, flags);
That would force all other cpus into the spin_lock path. Problem
solved, but that's way beyond the scope of this fix and really wants
to be implemented in a common function which calls the uart specific
write function to avoid another gazillion of hard to debug
copy/paste/modify bugs.
Reported-and-tested-by: Tim Sander <tim@krieglstein.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable <stable@vger.kernel.org> # 3.6+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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