In file included from kernel/crash_dump.c:2:0:
  include/linux/crash_dump.h:22:27: error: unknown type name `pgprot_t'

when CONFIG_CRASH_DUMP=y

The error was traced back to commit 9cb21813 ("vmcore: introduce
remap_oldmem_pfn_range()")

include <asm/pgtable.h> to get the missing definition
Signed-off-by: NQais Yousef <qais.yousef@imgtec.com>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: NVivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org>	[3.12+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add include guard to include/linux/platform_data/sht15.h to prevent
multiple inclusion.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Add include guard to include/linux/platform_data/max197.h to prevent
multiple inclusion.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

Commit 436d42c6 ("ARM: samsung: move platform_data definitions")
moved the file to the current location but forgot to remove the pointer
to its previous location. Clean it up. While at it also change the header
file protection macros appropriately.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

The body of i2c_parent_is_i2c_adapter() is currently guarded by
I2C_MUX. It should be CONFIG_I2C_MUX instead.

Among potentially other problems, this resulted in i2c_lock_adapter()
only locking I2C mux child adapters, and not the parent adapter. In
turn, this could allow inter-mingling of mux child selection and I2C
transactions, which could result in I2C transactions being directed to
the wrong I2C bus, and possibly even switching between busses in the
middle of a transaction.

One concrete issue caused by this bug was corrupted HDMI EDID reads
during boot on the NVIDIA Tegra Seaboard system, although this only
became apparent in recent linux-next, when the boot timing was changed
just enough to trigger the race condition.

Fixes: 3923172b ("i2c: reduce parent checking to a NOOP in non-I2C_MUX case")
Cc: Phil Carmody <phil.carmody@partner.samsung.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NStephen Warren <swarren@nvidia.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

A number of situations currently require the heavyweight smp_mb(),
even though there is no need to order prior stores against later
loads.  Many architectures have much cheaper ways to handle these
situations, but the Linux kernel currently has no portable way
to make use of them.

This commit therefore supplies smp_load_acquire() and
smp_store_release() to remedy this situation.  The new
smp_load_acquire() primitive orders the specified load against
any subsequent reads or writes, while the new smp_store_release()
primitive orders the specifed store against any prior reads or
writes.  These primitives allow array-based circular FIFOs to be
implemented without an smp_mb(), and also allow a theoretical
hole in rcu_assign_pointer() to be closed at no additional
expense on most architectures.

In addition, the RCU experience transitioning from explicit
smp_read_barrier_depends() and smp_wmb() to rcu_dereference()
and rcu_assign_pointer(), respectively resulted in substantial
improvements in readability.  It therefore seems likely that
replacing other explicit barriers with smp_load_acquire() and
smp_store_release() will provide similar benefits.  It appears
that roughly half of the explicit barriers in core kernel code
might be so replaced.

[Changelog by PaulMck]
Reviewed-by: N"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Acked-by: NWill Deacon <will.deacon@arm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/20131213150640.908486364@infradead.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Linus disliked the _no_lockdep() naming, so instead
use the more-consistent raw_* prefix to the non-lockdep
enabled seqcount methods.

This also adds raw_ methods for the write operations
as well, which will be utilized in a following patch.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: NStephen Boyd <sboyd@codeaurora.org>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Krzysztof Hałasa <khalasa@piap.pl>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Willy Tarreau <w@1wt.eu>
Link: http://lkml.kernel.org/r/1388704274-5278-1-git-send-email-john.stultz@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The
will cause several issues:

- NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan
  instead of lower device which misses the necessary txq synchronization for
  lower device such as txq stopping or frozen required by dev watchdog or
  control path.
- dev_hard_start_xmit() was called with NULL txq which bypasses the net device
  watchdog.
- dev_hard_start_xmit() does not check txq everywhere which will lead a crash
  when tso is disabled for lower device.

Fix this by explicitly introducing a new param for .ndo_select_queue() for just
selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also
extended to accept this parameter and dev_queue_xmit_accel() was used to do l2
forwarding transmission.

With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need
to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep
a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of
dev_queue_xmit() to do the transmission.

In the future, it was also required for macvtap l2 forwarding support since it
provides a necessary synchronization method.

Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: e1000-devel@lists.sourceforge.net
Signed-off-by: NJason Wang <jasowang@redhat.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

VM to VM GSO traffic is broken if it goes through VXLAN or GRE
tunnel and the physical NIC on the host supports hardware VXLAN/GRE
GSO offload (e.g. bnx2x and next-gen mlx4).

Two issues -
(VXLAN) VM traffic has SKB_GSO_DODGY and SKB_GSO_UDP_TUNNEL with
SKB_GSO_TCP/UDP set depending on the inner protocol. GSO header
integrity check fails in udp4_ufo_fragment if inner protocol is
TCP. Also gso_segs is calculated incorrectly using skb->len that
includes tunnel header. Fix: robust check should only be applied
to the inner packet.

(VXLAN & GRE) Once GSO header integrity check passes, NULL segs
is returned and the original skb is sent to hardware. However the
tunnel header is already pulled. Fix: tunnel header needs to be
restored so that hardware can perform GSO properly on the original
packet.
Signed-off-by: NWei-Chun Chao <weichunc@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the vlan code detects that the real device can do TX VLAN offloads
in hardware, it tries to arrange for the real device's header_ops to
be invoked directly.

But it does so illegally, by simply hooking the real device's
header_ops up to the VLAN device.

This doesn't work because we will end up invoking a set of header_ops
routines which expect a device type which matches the real device, but
will see a VLAN device instead.

Fix this by providing a pass-thru set of header_ops which will arrange
to pass the proper real device instead.

To facilitate this add a dev_rebuild_header().  There are
implementations which provide a ->cache and ->create but not a
->rebuild (f.e. PLIP).  So we need a helper function just like
dev_hard_header() to avoid crashes.

Use this helper in the one existing place where the
header_ops->rebuild was being invoked, the neighbour code.

With lots of help from Florian Westphal.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We've seen so many instances of people invoking skb_tx_timestamp()
after the device already has been given the packet, that it's worth
being a little bit more verbose and explicit in this comment.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 2171364d ("powerpc: Add HWCAP2 aux entry") introduced a new
AT_ auxv entry type AT_HWCAP2 but failed to update AT_VECTOR_SIZE_BASE
accordingly.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Fixes: 2171364d (powerpc: Add HWCAP2 aux entry)
Cc: stable@vger.kernel.org
Acked-by: NMichael Neuling <michael@neuling.org>
Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The arbitrary restriction on page counts offered by the core
migrate_page_move_mapping() code results in rather suspicious looking
fiddling with page reference counts in the aio_migratepage() operation.
To fix this, make migrate_page_move_mapping() take an extra_count parameter
that allows aio to tell the code about its own reference count on the page
being migrated.

While cleaning up aio_migratepage(), make it validate that the old page
being passed in is actually what aio_migratepage() expects to prevent
misbehaviour in the case of races.
Signed-off-by: NBenjamin LaHaise <bcrl@kvack.org>

Some pstore backing devices use on board flash as persistent
storage. These have limited numbers of write cycles so it
is a poor idea to use them from high frequency operations.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In struct page we have enough space to fit long-size page->ptl there,
but we use dynamically-allocated page->ptl if size(spinlock_t) is larger
than sizeof(int).

It hurts 64-bit architectures with CONFIG_GENERIC_LOCKBREAK, where
sizeof(spinlock_t) == 8, but it easily fits into struct page.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

According to documentation on barriers, stores issued before a LOCK can
complete after the lock implying that it's possible tlb_flush_pending
can be visible after a page table update.  As per revised documentation,
this patch adds a smp_mb__before_spinlock to guarantee the correct
ordering.
Signed-off-by: NMel Gorman <mgorman@suse.de>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NRik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are a few subtle races, between change_protection_range (used by
mprotect and change_prot_numa) on one side, and NUMA page migration and
compaction on the other side.

The basic race is that there is a time window between when the PTE gets
made non-present (PROT_NONE or NUMA), and the TLB is flushed.

During that time, a CPU may continue writing to the page.

This is fine most of the time, however compaction or the NUMA migration
code may come in, and migrate the page away.

When that happens, the CPU may continue writing, through the cached
translation, to what is no longer the current memory location of the
process.

This only affects x86, which has a somewhat optimistic pte_accessible.
All other architectures appear to be safe, and will either always flush,
or flush whenever there is a valid mapping, even with no permissions
(SPARC).

The basic race looks like this:

CPU A			CPU B			CPU C

						load TLB entry
make entry PTE/PMD_NUMA
			fault on entry
						read/write old page
			start migrating page
			change PTE/PMD to new page
						read/write old page [*]
flush TLB
						reload TLB from new entry
						read/write new page
						lose data

[*] the old page may belong to a new user at this point!

The obvious fix is to flush remote TLB entries, by making sure that
pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may
still be accessible if there is a TLB flush pending for the mm.

This should fix both NUMA migration and compaction.

[mgorman@suse.de: fix build]
Signed-off-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NMel Gorman <mgorman@suse.de>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

do_huge_pmd_numa_page() handles the case where there is parallel THP
migration.  However, by the time it is checked the NUMA hinting
information has already been disrupted.  This patch adds an earlier
check with some helpers.
Signed-off-by: NMel Gorman <mgorman@suse.de>
Reviewed-by: NRik van Riel <riel@redhat.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 1b3a5d02 ("reboot: move arch/x86 reboot= handling to generic
kernel") moved reboot= handling to generic code.  In the process it also
removed the code in native_machine_shutdown() which are moving reboot
process to reboot_cpu/cpu0.

I guess that thought must have been that all reboot paths are calling
migrate_to_reboot_cpu(), so we don't need this special handling.  But
kexec reboot path (kernel_kexec()) is not calling
migrate_to_reboot_cpu() so above change broke kexec.  Now reboot can
happen on non-boot cpu and when INIT is sent in second kerneo to bring
up BP, it brings down the machine.

So start calling migrate_to_reboot_cpu() in kexec reboot path to avoid
this problem.

Bisected by WANG Chao.
Reported-by: NMatthew Whitehead <mwhitehe@redhat.com>
Reported-by: NDave Young <dyoung@redhat.com>
Signed-off-by: NVivek Goyal <vgoyal@redhat.com>
Tested-by: NBaoquan He <bhe@redhat.com>
Tested-by: NWANG Chao <chaowang@redhat.com>
Acked-by: NH. Peter Anvin <hpa@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ipgre_header_parse() needs to parse the tunnel's ip header and it
uses mac_header to locate the iphdr. This got broken when gre tunneling
was refactored as mac_header is no longer updated to point to iphdr.
Introduce skb_pop_mac_header() helper to do the mac_header assignment
and use it in ipgre_rcv() to fix msg_name parsing.

Bug introduced in commit c5441932 (GRE: Refactor GRE tunneling code.)

Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: NTimo Teräs <timo.teras@iki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is useful to be able to walk all upper devices when bringing
a device online where the RTNL lock is held. In this case it
is safe to walk the all_adj_list because the RTNL lock is used
to protect the write side as well.

This patch adds a check to see if the rtnl lock is held before
throwing a warning in netdev_all_upper_get_next_dev_rcu().

Also because we now have a call site for lockdep_rtnl_is_held()
outside COFIG_LOCK_PROVING an inline definition returning 1 is
needed. Similar to the rcu_read_lock_is_held().

Fixes: 2a47fa45 ("ixgbe: enable l2 forwarding acceleration for macvlans")
CC: Veaceslav Falico <vfalico@redhat.com>
Reported-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Tested-by: NPhil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Certain drives cannot handle queued TRIM commands properly, even
though support is indicated in the IDENTIFY DEVICE buffer.  This patch
allows for disabling the commands for the affected drives and apply it
to the Micron/Crucial M500 SSDs which exhibit incorrect protocol
behavior when issued queued TRIM commands, which could lead to silent
data corruption.

tj: Merged two unnecessarily split patches and made minor edits
    including shortening horkage name.
Signed-off-by: NMarc Carino <marc.ceeeee@gmail.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/g/1387246554-7311-1-git-send-email-marc.ceeeee@gmail.com
Cc: stable@vger.kernel.org # 3.12+

The Linux kernel has traditionally required that an UNLOCK+LOCK
pair act as a full memory barrier when either (1) that
UNLOCK+LOCK pair was executed by the same CPU or task, or (2)
the same lock variable was used for the UNLOCK and LOCK.  It now
seems likely that very few places in the kernel rely on this
full-memory-barrier semantic, and with the advent of queued
locks, providing this semantic either requires complex
reasoning, or for some architectures, added overhead.

This commit therefore adds a smp_mb__after_unlock_lock(), which
may be placed after a LOCK primitive to restore the
full-memory-barrier semantic. All definitions are currently
no-ops, but will be upgraded for some architectures when queued
locks arrive.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <linux-arch@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1386799151-2219-5-git-send-email-paulmck@linux.vnet.ibm.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Rename old regmap field of "struct sec_pmic_dev" to "regmap_pmic" and
add new regmap for RTC.

On S5M8767A registers were not properly updated and read due to usage of
the same regmap as the PMIC.  This could be observed in various hangs,
e.g.  in infinite loop during waiting for UDR field change.

On this chip family the RTC has different I2C address than PMIC so
additional regmap is needed.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: NMark Brown <broonie@linaro.org>
Acked-by: NSangbeom Kim <sbkim73@samsung.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The machine cannot fault if !MUU, so make might_fault() a nop for !MMU.

This fixes below build error if
!CONFIG_MMU && (CONFIG_PROVE_LOCKING=y || CONFIG_DEBUG_ATOMIC_SLEEP=y):

  arch/arm/kernel/built-in.o: In function `arch_ptrace':
  arch/arm/kernel/ptrace.c:852: undefined reference to `might_fault'
  arch/arm/kernel/built-in.o: In function `restore_sigframe':
  arch/arm/kernel/signal.c:173: undefined reference to `might_fault'
  ...
  arch/arm/kernel/built-in.o:arch/arm/kernel/signal.c:177: more undefined references to `might_fault' follow
  make: *** [vmlinux] Error 1
Signed-off-by: NAxel Lin <axel.lin@ingics.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With CONFIG_HUGETLBFS=n:

  mm/migrate.c: In function `do_move_page_to_node_array':
  include/linux/hugetlb.h:140:33: warning: statement with no effect [-Wunused-value]
   #define isolate_huge_page(p, l) false
                                   ^
  mm/migrate.c:1170:4: note: in expansion of macro `isolate_huge_page'
      isolate_huge_page(page, &pagelist);
Reported-by: NBorislav Petkov <bp@alien8.de>
Tested-by: NBorislav Petkov <bp@alien8.de>
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

neigh_priv_len is defined as u8. With all debug enabled struct
ipoib_neigh has 200 bytes. The largest part is sk_buff_head with 96
bytes and here the spinlock with 72 bytes.
The size value still fits in this u8 leaving some room for more.

On -RT struct ipoib_neigh put on weight and has 392 bytes. The main
reason is sk_buff_head with 288 and the fatty here is spinlock with 192
bytes. This does no longer fit into into neigh_priv_len and gcc
complains.

This patch changes neigh_priv_len from being 8bit to 16bit. Since the
following element (dev_id) is 16bit followed by a spinlock which is
aligned, the struct remains with a total size of 3200 (allmodconfig) /
2048 (with as much debug off as possible) bytes on x86-64.
On x86-32 the struct is 1856 (allmodconfig) / 1216 (with as much debug
off as possible) bytes long. The numbers were gained with and without
the patch to prove that this change does not increase the size of the
struct.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Function prototypes don't need to have the "extern" keyword since this
is the default behavior. Its explicit use is redundant.  This commit
therefore removes them.
Signed-off-by: NTeodora Baluta <teobaluta@gmail.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

There is currently no way to initialize a global RCU-protected pointer
without either putting up with sparse complaints or open-coding an
obscure cast.  This commit therefore creates RCU_INITIALIZER(), which
is intended to be used as follows:

	struct foo __rcu *p = RCU_INITIALIZER(&my_rcu_structure);

This commit also applies RCU_INITIALIZER() to eliminate repeated
open-coded obscure casts in __rcu_assign_pointer(), RCU_INIT_POINTER(),
and RCU_POINTER_INITIALIZER().  This commit also inlines
__rcu_assign_pointer() into its only caller, rcu_assign_pointer().
Suggested-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

The rcu_assign_pointer() primitive needs to use ACCESS_ONCE to make
the assignment to the destination pointer volatile, to protect against
compilers too clever for their own good.
Signed-off-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

The rcu_assign_pointer() macro, as with most cpp macros, must not evaluate
its argument more than once.  And it in fact does not.  But this might
not be obvious to the casual observer, because one of the arguments
appears no less than three times.  However, but one expansion is only
visible to sparse (__CHECKER__), and one lives inside a typeof (where
it will never be evaluated), so this is in fact safe.

This commit therefore adds a comment making this explicit.
Reported-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

When explicitly hashing the end of a string with the word-at-a-time
interface, we have to be careful which end of the word we pick up.

On big-endian CPUs, the upper-bits will contain the data we're after, so
ensure we generate our masks accordingly (and avoid hashing whatever
random junk may have been sitting after the string).

This patch adds a new dcache helper, bytemask_from_count, which creates
a mask appropriate for the CPU endianness.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Renesas R-Car development boards use KSZ8041RNLI PHY which for some reason has
ID of 0x00221537 that is not documented for KSZ8041-family PHYs and does not
match the  documented ID of  0x0022151x (where 'x' is the revision).  We have
to add the new #define PHY_ID_* and new ksphy_driver[] entry, almost the same
as KSZ8041 one, differing only in the 'phy_id' and 'name' fields.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Tested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Christian suffers from a bad BIOS that wrecks his i5's TSC sync. This
results in him occasionally seeing time going backwards - which
crashes the scheduler ...

Most of our time accounting can actually handle that except the most
common one; the tick time update of sched_fair.

There is a further problem with that code; previously we assumed that
because we get a tick every TICK_NSEC our time delta could never
exceed 32bits and math was simpler.

However, ever since Frederic managed to get NO_HZ_FULL merged; this is
no longer the case since now a task can run for a long time indeed
without getting a tick. It only takes about ~4.2 seconds to overflow
our u32 in nanoseconds.

This means we not only need to better deal with time going backwards;
but also means we need to be able to deal with large deltas.

This patch reworks the entire code and uses mul_u64_u32_shr() as
proposed by Andy a long while ago.

We express our virtual time scale factor in a u32 multiplier and shift
right and the 32bit mul_u64_u32_shr() implementation reduces to a
single 32x32->64 multiply if the time delta is still short (common
case).

For 64bit a 64x64->128 multiply can be used if ARCH_SUPPORTS_INT128.
Reported-and-Tested-by: NChristian Engelmayer <cengelma@gmx.at>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
Cc: Paul Turner <pjt@google.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20131118172706.GI3866@twins.programming.kicks-ass.netSigned-off-by: NIngo Molnar <mingo@kernel.org>

Introduce mul_u64_u32_shr() as proposed by Andy a while back; it
allows using 64x64->128 muls on 64bit archs and recent GCC
which defines __SIZEOF_INT128__ and __int128.

(This new method will be used by the scheduler.)
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-hxjoeuzmrcaumR0uZwjpe2pv@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

While hunting a preemption issue with Alexander, Ben noticed that the
currently generic PREEMPT_NEED_RESCHED stuff is horribly broken for
load-store architectures.

We currently rely on the IPI to fold TIF_NEED_RESCHED into
PREEMPT_NEED_RESCHED, but when this IPI lands while we already have
a load for the preempt-count but before the store, the store will erase
the PREEMPT_NEED_RESCHED change.

The current preempt-count only works on load-store archs because
interrupts are assumed to be completely balanced wrt their preempt_count
fiddling; the previous preempt_count load will match the preempt_count
state after the interrupt and therefore nothing gets lost.

This patch removes the PREEMPT_NEED_RESCHED usage from generic code and
pushes it into x86 arch code; the generic code goes back to relying on
TIF_NEED_RESCHED.

Boot tested on x86_64 and compile tested on ppc64.
Reported-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Reported-and-Tested-by: NAlexander Graf <agraf@suse.de>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20131128132641.GP10022@twins.programming.kicks-ass.netSigned-off-by: NIngo Molnar <mingo@kernel.org>

unix_dgram_recvmsg() will hold the readlock of the socket until recv
is complete.

In the same time, we may try to setsockopt(SO_PEEK_OFF) which will hang until
unix_dgram_recvmsg() will complete (which can take a while) without allowing
us to break out of it, triggering a hung task spew.

Instead, allow set_peek_off to fail, this way userspace will not hang.
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When compiling with icc, <linux/compiler-gcc.h> ends up included
because the icc environment defines __GNUC__.  Thus, we neither need
nor want to have this macro defined in both compiler-gcc.h and
compiler-intel.h, and the fact that they are inconsistent just makes
the compiler spew warnings.
Reported-by: NSunil K. Pandey <sunil.k.pandey@intel.com>
Cc: Kevin B. Smith <kevin.b.smith@intel.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/n/tip-0mbwou1zt7pafij09b897lg3@git.kernel.org
Cc: <stable@vger.kernel.org>

Currently blocking in an RCU callback function will result in
"scheduling while atomic", which could be triggered for any number
of reasons.  To aid debugging, this patch introduces a rcu_callback_map
that is used to tie the inappropriate voluntary context switch back
to the fact that the function is being invoked from within a callback.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>

Commit 5a87182a (cpufreq: suspend governors on system
suspend/hibernate) causes hibernation problems to happen on
Bjørn Mork's and Paul Bolle's systems, so revert it.

Fixes: 5a87182a (cpufreq: suspend governors on system suspend/hibernate)
Reported-by: NBjørn Mork <bjorn@mork.no>
Reported-by: NPaul Bolle <pebolle@tiscali.nl>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>