Commit graph

602306 commits

Author SHA1 Message Date
Robin Murphy
5c1d3310d8 drivers: of: Fix of_pci.h header guard
The compilation of of_pci.c is governed by CONFIG_OF_PCI, but the
corresponding declarations in of_pci.h are inconsistently guarded by
CONFIG_OF, with the result that if CONFIG_PCI is disabled for an OF
platform, the dangling external declarations are still active and the
inline stub definitions not. So far this has managed to go unnoticed
since it happens that the only references to these functions are from
code which itself depends on CONFIG_PCI or CONFIG_OF_PCI.

Fix this with the appropriate config guard so that any new callers
outside PCI-specific code don't start unexpectedly breaking under
certain configs.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2016-06-08 08:18:06 -05:00
Fabio Estevam
3eefa7e8cc dt-bindings: Add vendor prefix for TechNexion
TechNexion designs and manufactures embedded computing systems:
http://www.technexion.com/

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Rob Herring <robh@kernel.org>
2016-06-08 08:13:31 -05:00
Josh Poimboeuf
4698f88c06 sched/debug: Fix 'schedstats=enable' cmdline option
The 'schedstats=enable' option doesn't work, and also produces the
following warning during boot:

  WARNING: CPU: 0 PID: 0 at /home/jpoimboe/git/linux/kernel/jump_label.c:61 static_key_slow_inc+0x8c/0xa0
  static_key_slow_inc used before call to jump_label_init
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 4.7.0-rc1+ #25
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
   0000000000000086 3ae3475a4bea95d4 ffffffff81e03da8 ffffffff8143fc83
   ffffffff81e03df8 0000000000000000 ffffffff81e03de8 ffffffff810b1ffb
   0000003d00000096 ffffffff823514d0 ffff88007ff197c8 0000000000000000
  Call Trace:
   [<ffffffff8143fc83>] dump_stack+0x85/0xc2
   [<ffffffff810b1ffb>] __warn+0xcb/0xf0
   [<ffffffff810b207f>] warn_slowpath_fmt+0x5f/0x80
   [<ffffffff811e9c0c>] static_key_slow_inc+0x8c/0xa0
   [<ffffffff810e07c6>] static_key_enable+0x16/0x40
   [<ffffffff8216d633>] setup_schedstats+0x29/0x94
   [<ffffffff82148a05>] unknown_bootoption+0x89/0x191
   [<ffffffff810d8617>] parse_args+0x297/0x4b0
   [<ffffffff82148d61>] start_kernel+0x1d8/0x4a9
   [<ffffffff8214897c>] ? set_init_arg+0x55/0x55
   [<ffffffff82148120>] ? early_idt_handler_array+0x120/0x120
   [<ffffffff821482db>] x86_64_start_reservations+0x2f/0x31
   [<ffffffff82148427>] x86_64_start_kernel+0x14a/0x16d

The problem is that it tries to update the 'sched_schedstats' static key
before jump labels have been initialized.

Changing jump_label_init() to be called earlier before
parse_early_param() wouldn't fix it: it would still fail trying to
poke_text() because mm isn't yet initialized.

Instead, just create a temporary '__sched_schedstats' variable which can
be copied to the static key later during sched_init() after jump labels
have been initialized.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: cb2517653f ("sched/debug: Make schedstats a runtime tunable that is disabled by default")
Link: http://lkml.kernel.org/r/453775fe3433bed65731a583e228ccea806d18cd.1465322027.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 14:33:05 +02:00
Josh Poimboeuf
9c57259117 sched/debug: Fix /proc/sched_debug regression
Commit:

  cb2517653f ("sched/debug: Make schedstats a runtime tunable that is disabled by default")

... introduced a bug when CONFIG_SCHEDSTATS is enabled and the
runtime tunable is disabled (which is the default).

The wait-time, sum-exec, and sum-sleep fields are missing from the
/proc/sched_debug file in the runnable_tasks section.

Fix it with a new schedstat_val() macro which returns the field value
when schedstats is enabled and zero otherwise.  The macro works with
both SCHEDSTATS and !SCHEDSTATS.  I put the macro in stats.h since it
might end up being useful in other places.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: cb2517653f ("sched/debug: Make schedstats a runtime tunable that is disabled by default")
Link: http://lkml.kernel.org/r/bcda7c2790cf2ccbe586a28c02dd7b6fe7749a2b.1464994423.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 14:31:58 +02:00
Alexander Shishkin
62a92c8f55 perf/core: Remove a redundant check
There is no way to end up in _free_event() with event::pmu being NULL.
The latter is initialized in event allocation path and remains set
forever. In case of allocation failure, the error path doesn't use
_free_event().

Having the check, however, suggests that it is possible to have a
event::pmu==NULL situation in _free_event() and confuses the robots.

This patch gets rid of the check.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: eranian@google.com
Cc: vince@deater.net
Link: http://lkml.kernel.org/r/1465303455-26032-1-git-send-email-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 14:30:01 +02:00
Peter Zijlstra
2c61002271 locking/qspinlock: Fix spin_unlock_wait() some more
While this prior commit:

  54cf809b95 ("locking,qspinlock: Fix spin_is_locked() and spin_unlock_wait()")

... fixes spin_is_locked() and spin_unlock_wait() for the usage
in ipc/sem and netfilter, it does not in fact work right for the
usage in task_work and futex.

So while the 2 locks crossed problem:

	spin_lock(A)		spin_lock(B)
	if (!spin_is_locked(B)) spin_unlock_wait(A)
	  foo()			foo();

... works with the smp_mb() injected by both spin_is_locked() and
spin_unlock_wait(), this is not sufficient for:

	flag = 1;
	smp_mb();		spin_lock()
	spin_unlock_wait()	if (!flag)
				  // add to lockless list
	// iterate lockless list

... because in this scenario, the store from spin_lock() can be delayed
past the load of flag, uncrossing the variables and loosing the
guarantee.

This patch reworks spin_is_locked() and spin_unlock_wait() to work in
both cases by exploiting the observation that while the lock byte
store can be delayed, the contender must have registered itself
visibly in other state contained in the word.

It also allows for architectures to override both functions, as PPC
and ARM64 have an additional issue for which we currently have no
generic solution.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Giovanni Gherdovich <ggherdovich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <waiman.long@hpe.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org # v4.2 and later
Fixes: 54cf809b95 ("locking,qspinlock: Fix spin_is_locked() and spin_unlock_wait()")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 14:29:08 +02:00
Ben Dooks
b66b2a0adf gpio: bcm-kona: fix bcm_kona_gpio_reset() warnings
The bcm_kona_gpio_reset() calls bcm_kona_gpio_write_lock_regs()
with what looks like the wrong parameter. The write_lock_regs
function takes a pointer to the registers, not the bcm_kona_gpio
structure.

Fix the warning, and probably bug by changing the function to
pass reg_base instead of kona_gpio, fixing the following warning:

drivers/gpio/gpio-bcm-kona.c:550:47: warning: incorrect type in argument 1
  (different address spaces)
  expected void [noderef] <asn:2>*reg_base
  got struct bcm_kona_gpio *kona_gpio
  warning: incorrect type in argument 1 (different address spaces)
  expected void [noderef] <asn:2>*reg_base
  got struct bcm_kona_gpio *kona_gpio

Cc: stable@vger.kernel.org
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Reviewed-by: Markus Mayer <mmayer@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 14:04:35 +02:00
Borislav Petkov
96685a55a8 x86/cpu/AMD: Extend X86_FEATURE_TOPOEXT workaround to newer models
We need to reenable the topology extensions CPUID leafs on newer models
too, if BIOS has disabled them, as we rely on them to get proper compute
unit topology.

Make the printk a once thing, while at it.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rui Huang <ray.huang@amd.com>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-hwmon@vger.kernel.org
Link: http://lkml.kernel.org/r/1464775468-23355-1-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 13:51:34 +02:00
Linus Walleij
60a5eaba46 gpio: select ANON_INODES
The build servers found that gpiolib is using ANON_INODES but
has forgotten to select it. Fix this.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 521a2ad6f8 ("gpio: add userspace ABI for GPIO line information")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 13:47:37 +02:00
Dave Hansen
970442c599 x86/cpu/intel: Introduce macros for Intel family numbers
Problem:

We have a boatload of open-coded family-6 model numbers.  Half of
them have these model numbers in hex and the other half in
decimal.  This makes grepping for them tons of fun, if you were
to try.

Solution:

Consolidate all the magic numbers.  Put all the definitions in
one header.

The names here are closely derived from the comments describing
the models from arch/x86/events/intel/core.c.  We could easily
make them shorter by doing things like s/SANDYBRIDGE/SNB/, but
they seemed fine even with the longer versions to me.

Do not take any of these names too literally, like "DESKTOP"
or "MOBILE".  These are all colloquial names and not precise
descriptions of everywhere a given model will show up.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Rajneesh Bhardwaj <rajneesh.bhardwaj@intel.com>
Cc: Souvik Kumar Chakravarty <souvik.k.chakravarty@intel.com>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Vishwanath Somayaji <vishwanath.somayaji@intel.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: jacob.jun.pan@intel.com
Cc: linux-acpi@vger.kernel.org
Cc: linux-edac@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: platform-driver-x86@vger.kernel.org
Link: http://lkml.kernel.org/r/20160603001927.F2A7D828@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 11:59:09 +02:00
Will Deacon
0106d456c4 arm64: mm: always take dirty state from new pte in ptep_set_access_flags
Commit 66dbd6e61a ("arm64: Implement ptep_set_access_flags() for
hardware AF/DBM") ensured that pte flags are updated atomically in the
face of potential concurrent, hardware-assisted updates. However, Alex
reports that:

 | This patch breaks swapping for me.
 | In the broken case, you'll see either systemd cpu time spike (because
 | it's stuck in a page fault loop) or the system hang (because the
 | application owning the screen is stuck in a page fault loop).

It turns out that this is because the 'dirty' argument to
ptep_set_access_flags is always 0 for read faults, and so we can't use
it to set PTE_RDONLY. The failing sequence is:

  1. We put down a PTE_WRITE | PTE_DIRTY | PTE_AF pte
  2. Memory pressure -> pte_mkold(pte) -> clear PTE_AF
  3. A read faults due to the missing access flag
  4. ptep_set_access_flags is called with dirty = 0, due to the read fault
  5. pte is then made PTE_WRITE | PTE_DIRTY | PTE_AF | PTE_RDONLY (!)
  6. A write faults, but pte_write is true so we get stuck

The solution is to check the new page table entry (as would be done by
the generic, non-atomic definition of ptep_set_access_flags that just
calls set_pte_at) to establish the dirty state.

Cc: <stable@vger.kernel.org> # 4.3+
Fixes: 66dbd6e61a ("arm64: Implement ptep_set_access_flags() for hardware AF/DBM")
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Alexander Graf <agraf@suse.de>
Tested-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-06-08 10:23:44 +01:00
Linus Walleij
7d4defe21c gpio: include <linux/io-mapping.h> in gpiolib-of
When enabling the gpiolib for all archs a build robot came
up with this:

All errors (new ones prefixed by >>):

   drivers/gpio/gpiolib-of.c: In function 'of_mm_gpiochip_add_data':
>> drivers/gpio/gpiolib-of.c:317:2: error: implicit declaration of
   function 'iounmap' [-Werror=implicit-function-declaration]
     iounmap(mm_gc->regs);
     ^~~~~~~
   cc1: some warnings being treated as errors

Fix this by including <linux/io-mapping.h> explicitly.

Fixes: 296ad4acb8 ("gpio: remove deps on ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:58:20 +02:00
Ricardo Ribalda Delgado
f4833b8cc7 gpiolib: Fix unaligned used of reference counters
gpiolib relies on the reference counters to clean up the gpio_device
structure.

Although the number of get/put is properly aligned on gpiolib.c
itself, it does not take into consideration how the referece counters
are affected by other external functions such as cdev_add and device_add.

Because of this, after the last call to put_device, the reference counter
has a value of +3, therefore never calling gpiodevice_release.

Due to the fact that some of the device  has already been cleaned on
gpiochip_remove, the library will end up OOPsing the kernel (e.g. a call
to of_gpiochip_find_and_xlate).

Cc: stable@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:40:29 +02:00
Ricardo Ribalda Delgado
11f33a6d15 gpiolib: Fix NULL pointer deference
Under some circumstances, a gpiochip might be half cleaned from the
gpio_device list.

This patch makes sure that the chip pointer is still valid, before
calling the match function.

[  104.088296] BUG: unable to handle kernel NULL pointer dereference at
0000000000000090
[  104.089772] IP: [<ffffffff813d2045>] of_gpiochip_find_and_xlate+0x15/0x80
[  104.128273] Call Trace:
[  104.129802]  [<ffffffff813d2030>] ? of_parse_own_gpio+0x1f0/0x1f0
[  104.131353]  [<ffffffff813cd910>] gpiochip_find+0x60/0x90
[  104.132868]  [<ffffffff813d21ba>] of_get_named_gpiod_flags+0x9a/0x120
...
[  104.141586]  [<ffffffff8163d12b>] gpio_led_probe+0x11b/0x360

Cc: stable@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:38:03 +02:00
Helmut Grohne
0f84f29ff3 gpio: zynq: initialize clock even without CONFIG_PM
When the PM initialization was moved in the commit referenced below, the
code enabling the clock was removed from the probe function. On
CONFIG_PM=y kernels, this is not a problem as the pm resume hook enables
the clock, but when power management is disabled, all those pm_*
functions are noops and the clock is never enabled resulting in a
dysfunctional gpio controller.

Put the clock initialization back to support CONFIG_PM=n.

Cc: stable@vger.kernel.org
Signed-off-by: Helmut Grohne <h.grohne@intenta.de>
Fixes: 3773c195d3 ("gpio: zynq: Do PM initialization earlier to support gpio hogs")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:36:29 +02:00
William Breathitt Gray
d15d6cf916 gpio: 104-dio-48e: Fix control port offset computation off-by-one error
There are only two control ports, each controlling three distinct I/O
ports. To compute the control port address offset for a respective I/O
port, the I/O port address offset should be divided by 3; dividing by 2
may result in not only the wrong address offset but possibly also an
out-of-bounds array memory access for a non-existent third control port.

Fixes: 1b06d64f73 ("gpio: Add GPIO support for the ACCES 104-DIO-48E")
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-08 10:08:12 +02:00
Ben Dooks
88832a22d6 net-sysfs: fix missing <linux/of_net.h>
The of_find_net_device_by_node() function is defined in
<linux/of_net.h> but not included in the .c file that
implements it. Fix the following warning by including the
header:

net/core/net-sysfs.c:1494:19: warning: symbol 'of_find_net_device_by_node' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 00:37:58 -07:00
Toshiaki Makita
0b148def40 bridge: Don't insert unnecessary local fdb entry on changing mac address
The missing br_vlan_should_use() test caused creation of an unneeded
local fdb entry on changing mac address of a bridge device when there is
a vlan which is configured on a bridge port but not on the bridge
device.

Fixes: 2594e9064a ("bridge: vlan: add per-vlan struct and move to rhashtables")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08 00:31:38 -07:00
Aneesh Kumar K.V
3b6d1eb7ea powerpc/mm/hash: Compute the segment size correctly for ISA 3.0
PowerISA 3.0 encodes the segment size in the second half of hash page
table entry. Update hpte_decode() accordingly.

Fixes: 50de596de8 ("powerpc/mm/hash: Add support for Power9 Hash")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08 14:36:22 +10:00
Aneesh Kumar K.V
9690c15742 powerpc/mm/radix: Fix always false comparison against MMU_NO_CONTEXT
In some of the radix TLB flush routines, we use a local to store the
mm->context.id, AKA the PID.

Currently we use an int, but the PID is unsigned long, so large values
of PID will be truncated. In particular MMU_NO_CONTEXT is -1, which
means all our comparisons against that value can never be true.

This means we'll issue TLB flushes when we shouldn't on radix enabled
machines.

Fix it by using an unsigned long for the local. Discovered by Coverity.

Fixes: 1a472c9dba ("powerpc/mm/radix: Add tlbflush routines")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Write change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08 13:56:53 +10:00
Linus Torvalds
c8ae067f26 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "Fixes for crap of assorted ages: EOPENSTALE one is 4.2+, autofs one is
  4.6, d_walk - 3.2+.

  The atomic_open() and coredump ones are regressions from this window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  coredump: fix dumping through pipes
  fix a regression in atomic_open()
  fix d_walk()/non-delayed __d_free() race
  autofs braino fix for do_last()
  fix EOPENSTALE bug in do_last()
2016-06-07 20:41:36 -07:00
Wolfram Sang
38bab98a8d hwmon: (lm90) use proper type for update_interval
The code handles this variable always as unsigned, so adapt the type.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-06-07 20:13:05 -07:00
Krzysztof Kozlowski
1069ad8f65 hwmon: (ina2xx) Document compatible for INA231
Document the compatible for INA231 sensor.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-06-07 20:11:38 -07:00
Borislav Petkov
7be4881846 hwmon: (fam15h_power) Disable preemption when reading registers
We need to read a bunch of registers on each compute unit and possibly
on the current CPU too. Disable preemption around it. Otherwise, you
get:

  BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/327
  caller is read_registers+0x6a/0x110 [fam15h_power]
  CPU: 3 PID: 327 Comm: systemd-udevd Not tainted 4.7.0-rc1+ #4
  Hardware name: HP HP EliteBook 745 G3/807E, BIOS N73 Ver. 01.08 01/28/2016
  ...

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Rui Huang <ray.huang@amd.com>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Acked-by: Huang Rui <ray.huang@amd.com>
Tested-by: Huang Rui <ray.huang@amd.com>
Fixes: fa79434499 ("hwmon: (fam15h_power) Add compute unit accumulated power")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2016-06-07 20:11:10 -07:00
Mateusz Guzik
1607f09c22 coredump: fix dumping through pipes
The offset in the core file used to be tracked with ->written field of
the coredump_params structure. The field was retired in favour of
file->f_pos.

However, ->f_pos is not maintained for pipes which leads to breakage.

Restore explicit tracking of the offset in coredump_params. Introduce
->pos field for this purpose since ->written was already reused.

Fixes: a008393951 ("get rid of coredump_params->written").

Reported-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-07 22:07:09 -04:00
Al Viro
a01e718f72 fix a regression in atomic_open()
open("/foo/no_such_file", O_RDONLY | O_CREAT) on should fail with
EACCES when /foo is not writable; failing with ENOENT is obviously
wrong.  That got broken by a braino introduced when moving the
creat_error logics from atomic_open() to lookup_open().  Easy to
fix, fortunately.

Spotted-by: "Yan, Zheng" <ukernel@gmail.com>
Tested-by: "Yan, Zheng" <ukernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-07 21:53:51 -04:00
Al Viro
3d56c25e3b fix d_walk()/non-delayed __d_free() race
Ascend-to-parent logics in d_walk() depends on all encountered child
dentries not getting freed without an RCU delay.  Unfortunately, in
quite a few cases it is not true, with hard-to-hit oopsable race as
the result.

Fortunately, the fix is simiple; right now the rule is "if it ever
been hashed, freeing must be delayed" and changing it to "if it
ever had a parent, freeing must be delayed" closes that hole and
covers all cases the old rule used to cover.  Moreover, pipes and
sockets remain _not_ covered, so we do not introduce RCU delay in
the cases which are the reason for having that delay conditional
in the first place.

Cc: stable@vger.kernel.org # v3.2+ (and watch out for __d_materialise_dentry())
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-07 21:26:55 -04:00
Srinivas Pandruvada
983e600e88 cpufreq: intel_pstate: Fix ->set_policy() interface for no_turbo
When turbo is disabled, the ->set_policy() interface is broken.

For example, when turbo is disabled and cpuinfo.max = 2900000 (full
max turbo frequency), setting the limits results in frequency less
than the requested one:
Set 1000000 KHz results in 0700000 KHz
Set 1500000 KHz results in 1100000 KHz
Set 2000000 KHz results in  1500000 KHz

This is because the limits->max_perf fraction is calculated using
the max turbo frequency as the reference, but when the max P-State is
capped in intel_pstate_get_min_max(), the reference is not the max
turbo P-State. This results in reducing max P-State.

One option is to always use max turbo as reference for calculating
limits. But this will not be correct. By definition the intel_pstate
sysfs limits, shows percentage of available performance. So when
BIOS has disabled turbo, the available performance is max non turbo.
So the max_perf_pct should still show 100%.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw : Subject & changelog, rewrite in fewer lines of code ]
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-08 03:22:40 +02:00
Srinivas Pandruvada
2c2c1af449 cpufreq: intel_pstate: Fix code ordering in intel_pstate_set_policy()
The limits->max_perf is rounded_up but immediately overwritten by
another assignment to limits->max_perf.

Move that operation to the correct location.

While here also added a pr_debug() call in ->set_policy to aid in
debugging.

Fixes: 785ee27881 (cpufreq: intel_pstate: Fix limits->max_perf rounding error)
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw : Subject & changelog ]
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-08 03:22:39 +02:00
Wolfram Sang
b3c0a4dab7 of: fix autoloading due to broken modalias with no 'compatible'
Because of an improper dereference, a stray 'C' character was output to
the modalias when no 'compatible' was specified. This is the case for
some old PowerMac drivers which only set the 'name' property. Fix it to
let them match again.

Reported-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Mathieu Malaterre <malat@debian.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Fixes: 6543becf26 ("mod/file2alias: make modalias generation safe for cross compiling")
Cc: stable@vger.kernel.org # v3.9+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08 10:40:20 +10:00
Michael Ellerman
2c2a63e301 powerpc/pseries: Fix IBM_ARCH_VEC_NRCORES_OFFSET since POWER8NVL was added
The recent commit 7cc851039d ("powerpc/pseries: Add POWER8NVL support
to ibm,client-architecture-support call") added a new PVR mask & value
to the start of the ibm_architecture_vec[] array.

However it missed the fact that further down in the array, we hard code
the offset of one of the fields, and then at boot use that value to
patch the value in the array. This means every update to the array must
also update the #define, ugh.

This means that on pseries machines we will misreport to firmware the
number of cores we support, by a factor of threads_per_core.

Fix it for now by updating the #define.

Fixes: 7cc851039d ("powerpc/pseries: Add POWER8NVL support to ibm,client-architecture-support call")
Cc: stable@vger.kernel.org # v4.0+
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-06-08 10:40:05 +10:00
David S. Miller
3256564458 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

The following patchset contains two Netfilter/IPVS fixes for your net
tree, they are:

1) Fix missing alignment in next offset calculation for standard
   targets, introduced in the previous merge window, patch from
   Florian Westphal.

2) Fix to correct the handling of outgoing connections which use the
   SIP-pe such that the binding of a real-server is updated when needed.
   This was an omission from changes introduced by Marco Angaroni in
   the previous merge window too, to allow handling of outgoing
   connections by the SIP-pe. Patch and report came via Simon Horman.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 17:14:10 -07:00
Yuchung Cheng
ce3cf4ec03 tcp: record TLP and ER timer stats in v6 stats
The v6 tcp stats scan do not provide TLP and ER timer information
correctly like the v4 version . This patch fixes that.

Fixes: 6ba8a3b19e ("tcp: Tail loss probe (TLP)")
Fixes: eed530b6c6 ("tcp: early retransmit")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 17:12:22 -07:00
Daniel Borkmann
92c075dbde net: sched: fix tc_should_offload for specific clsact classes
When offloading classifiers such as u32 or flower to hardware, and the
qdisc is clsact (TC_H_CLSACT), then we need to differentiate its classes,
since not all of them handle ingress, therefore we must leave those in
software path. Add a .tcf_cl_offload() callback, so we can generically
handle them, tested on ixgbe.

Fixes: 10cbc68434 ("net/sched: cls_flower: Hardware offloaded filters statistics support")
Fixes: 5b33f48842 ("net/flower: Introduce hardware offload support")
Fixes: a1b7c5fd7f ("net: sched: add cls_u32 offload hooks for netdevs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:59:53 -07:00
WANG Cong
a03e6fe569 act_police: fix a crash during removal
The police action is using its own code to initialize tcf hash
info, which makes us to forgot to initialize a->hinfo correctly.
Fix this by calling the helper function tcf_hash_create() directly.

This patch fixed the following crash:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
 IP: [<ffffffff810c099f>] __lock_acquire+0xd3/0xf91
 PGD d3c34067 PUD d3e18067 PMD 0
 Oops: 0000 [#1] SMP
 CPU: 2 PID: 853 Comm: tc Not tainted 4.6.0+ #87
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 task: ffff8800d3e28040 ti: ffff8800d3f6c000 task.ti: ffff8800d3f6c000
 RIP: 0010:[<ffffffff810c099f>]  [<ffffffff810c099f>] __lock_acquire+0xd3/0xf91
 RSP: 0000:ffff88011b203c80  EFLAGS: 00010002
 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000028
 RBP: ffff88011b203d40 R08: 0000000000000001 R09: 0000000000000000
 R10: ffff88011b203d58 R11: ffff88011b208000 R12: 0000000000000001
 R13: ffff8800d3e28040 R14: 0000000000000028 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff88011b200000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000028 CR3: 00000000d4be1000 CR4: 00000000000006e0
 Stack:
  ffff8800d3e289c0 0000000000000046 000000001b203d60 ffffffff00000000
  0000000000000000 ffff880000000000 0000000000000000 ffffffff00000000
  ffffffff8187142c ffff88011b203ce8 ffff88011b203ce8 ffffffff8101dbfc
 Call Trace:
  <IRQ>
  [<ffffffff8187142c>] ? __tcf_hash_release+0x77/0xd1
  [<ffffffff8101dbfc>] ? native_sched_clock+0x1a/0x35
  [<ffffffff8101dbfc>] ? native_sched_clock+0x1a/0x35
  [<ffffffff810a9604>] ? sched_clock_local+0x11/0x78
  [<ffffffff810bf6a1>] ? mark_lock+0x24/0x201
  [<ffffffff810c1dbd>] lock_acquire+0x120/0x1b4
  [<ffffffff810c1dbd>] ? lock_acquire+0x120/0x1b4
  [<ffffffff8187142c>] ? __tcf_hash_release+0x77/0xd1
  [<ffffffff81aad89f>] _raw_spin_lock_bh+0x3c/0x72
  [<ffffffff8187142c>] ? __tcf_hash_release+0x77/0xd1
  [<ffffffff8187142c>] __tcf_hash_release+0x77/0xd1
  [<ffffffff81871a27>] tcf_action_destroy+0x49/0x7c
  [<ffffffff81870b1c>] tcf_exts_destroy+0x20/0x2d
  [<ffffffff8189273b>] u32_destroy_key+0x1b/0x4d
  [<ffffffff81892788>] u32_delete_key_freepf_rcu+0x1b/0x1d
  [<ffffffff810de3b8>] rcu_process_callbacks+0x610/0x82e
  [<ffffffff8189276d>] ? u32_destroy_key+0x4d/0x4d
  [<ffffffff81ab0bc1>] __do_softirq+0x191/0x3f4

Fixes: ddf97ccdd7 ("net_sched: add network namespace support for tc actions")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:38:59 -07:00
Eric Dumazet
aafddbf0cf fq_codel: return non zero qlen in class dumps
We properly scan the flow list to count number of packets,
but John passed 0 to gnet_stats_copy_queue() so we report
a zero value to user space instead of the result.

Fixes: 6401585366 ("net: sched: restrict use of qstats qlen")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: John Fastabend <john.r.fastabend@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:28:11 -07:00
David S. Miller
064d5e6f8e Merge branch 'u32-hwoffload-fixes'
Jakub Kicinski says:

====================
cls_u32 hardware offload fixes

This set fixes two small issues with error codes I noticed
in cls_u32.  Second patch could be viewed as user space API
change but that portion of API is not part of any release,
yet.

Compile tested only.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:27:15 -07:00
Jakub Kicinski
d47a0f387f net: cls_u32: be more strict about skip-sw flag
Return an error if user requested skip-sw and the underlaying
hardware cannot handle tc offloads (or offloads are disabled).

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:27:14 -07:00
Jakub Kicinski
1a0f7d2984 net: cls_u32: fix error code for invalid flags
'err' variable is not set in this test, we would return whatever
previous test set 'err' to.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:27:14 -07:00
Colin Ian King
7b01b8e847 gtp: #define _UAPI_LINUX_GTP_H_ and not _UAPI_LINUX_GTP_H__
Fix clang build warning:

./include/uapi/linux/gtp.h:1:9: warning: '_UAPI_LINUX_GTP_H_' is
used as a header guard here, followed by #define of a different
macro [-Wheader-guard]

fix by defining  _UAPI_LINUX_GTP_H_ and not _UAPI_LINUX_GTP_H__

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:25:49 -07:00
Linus Torvalds
2051877c4c This finally removes the CLK_IS_ROOT flag by picking up the last few
stragglers that didn't get merged by anyone this time around. Better to
 do it now than wait for another one to pop up. There's also a minor
 maintainers update and a Kconfig fix.
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Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk fixes from Stephen Boyd:
 "This finally removes the CLK_IS_ROOT flag by picking up the last few
  stragglers that didn't get merged by anyone this time around.

  Better to do it now than wait for another one to pop up.  There's also
  a minor maintainers update and a Kconfig fix"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: nxp: Select MFD_SYSCON for creg driver
  MAINTAINERS: Add file patterns for clock device tree bindings
  clk: Remove CLK_IS_ROOT flag
  clk: microchip: Remove CLK_IS_ROOT
  powerpc/512x: clk: Remove CLK_IS_ROOT
  vexpress/spc: Remove CLK_IS_ROOT
2016-06-07 16:24:44 -07:00
Colin Ian King
9f647a6de9 net: fec: fix spelling mistakes and add missing newline
trivial fix to spelling mistakes and add missing newline in pr_err
messages

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Fugang Duan <fugang.duan@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:15:59 -07:00
David S. Miller
71743ffa15 Merge branch 'bnxt_en-fixes'
Michael Chan says:

====================
bnxt_en: Bug fixes.

Fix a race condition and VLAN rx acceleration logic.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:02:04 -07:00
Michael Chan
8852ddb4dc bnxt_en: Simplify VLAN receive logic.
Since both CTAG and STAG rx acceleration must be enabled together, we
only need to check one feature flag (NETIF_F_HW_VLAN_CTAG_RX) before
calling __vlan_hwaccel_put_tag().

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:02:03 -07:00
Michael Chan
5a9f6b238e bnxt_en: Enable and disable RX CTAG and RX STAG VLAN acceleration together.
The hardware can only be set to strip or not strip both the VLAN CTAG and
STAG.  It cannot strip one and not strip the other.  Add logic to
bnxt_fix_features() to toggle both feature flags when the user is toggling
one of them.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:02:03 -07:00
Michael Chan
b9a8460a08 bnxt_en: Fix tx push race condition.
Set the is_push flag in the software BD before the tx data is pushed to
the chip.  It is possible to get the tx interrupt as soon as the tx data
is pushed.  The tx handler will not handle the event properly if the
is_push flag is not set and it will crash.

Signed-off-by: Michael Chan <michael.chan@broadocm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 16:02:03 -07:00
H. Peter Anvin
9c77679cad x86, build: copy ldlinux.c32 to image.iso
For newer versions of Syslinux, we need ldlinux.c32 in addition to
isolinux.bin to reside on the boot disk, so if the latter is found,
copy it, too, to the isoimage tree.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Linux Stable Tree <stable@vger.kernel.org>
2016-06-07 15:54:18 -07:00
Wu Fengguang
fa54cc70ed rxrpc: fix ptr_ret.cocci warnings
net/rxrpc/rxkad.c:1165:1-3: WARNING: PTR_ERR_OR_ZERO can be used

 Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci

CC: David Howells <dhowells@redhat.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 15:30:21 -07:00
David S. Miller
29a36611e9 Merge branch 'rds-packet-assembly-fixes'
Sowmini Varadhan says:

====================
RDS: TCP: socket locking RDS packet assembly fixes

This three part patchset fixes bugs in synchronization between
rds_tcp_accept_one() and the rds-tcp send/recv path.

Patch 1 ensures that the lock_sock() is taken appropriately
and the RDS datagram reassembly state is reset  to synchronize
with the receive path.

Patch 2 ensures that partially sent RDS datagrams will get
retransmitted after rds_tcp_accept_one() switches sockets.

Patch 3 fixes a race window which would prematurely re-enable
rds_send_xmit() before the rds_tcp_connection setup has been
completed in rds_tcp_accept_one().
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 15:10:16 -07:00
Sowmini Varadhan
9c79440e2c RDS: TCP: fix race windows in send-path quiescence by rds_tcp_accept_one()
The send path needs to be quiesced before resetting callbacks from
rds_tcp_accept_one(), and commit eb19284026 ("RDS:TCP: Synchronize
rds_tcp_accept_one with rds_send_xmit when resetting t_sock") achieves
this using the c_state and RDS_IN_XMIT bit following the pattern
used by rds_conn_shutdown(). However this leaves the possibility
of a race window as shown in the sequence below
    take t_conn_lock in rds_tcp_conn_connect
    send outgoing syn to peer
    drop t_conn_lock in rds_tcp_conn_connect
    incoming from peer triggers rds_tcp_accept_one, conn is
	marked CONNECTING
    wait for RDS_IN_XMIT to quiesce any rds_send_xmit threads
    call rds_tcp_reset_callbacks
    [.. race-window where incoming syn-ack can cause the conn
	to be marked UP from rds_tcp_state_change ..]
    lock_sock called from rds_tcp_reset_callbacks, and we set
	t_sock to null
As soon as the conn is marked UP in the race-window above, rds_send_xmit()
threads will proceed to rds_tcp_xmit and may encounter a null-pointer
deref on the t_sock.

Given that rds_tcp_state_change() is invoked in softirq context, whereas
rds_tcp_reset_callbacks() is in workq context, and testing for RDS_IN_XMIT
after lock_sock could result in a deadlock with tcp_sendmsg, this
commit fixes the race by using a new c_state, RDS_TCP_RESETTING, which
will prevent a transition to RDS_CONN_UP from rds_tcp_state_change().

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-07 15:10:15 -07:00