4521 Commits

Author SHA1 Message Date
Linus Torvalds
710d60cbf1 Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull cpu hotplug updates from Thomas Gleixner:
 "This is the first part of the ongoing cpu hotplug rework:

   - Initial implementation of the state machine

   - Runs all online and prepare down callbacks on the plugged cpu and
     not on some random processor

   - Replaces busy loop waiting with completions

   - Adds tracepoints so the states can be followed"

More detailed commentary on this work from an earlier email:
 "What's wrong with the current cpu hotplug infrastructure?

   - Asymmetry

     The hotplug notifier mechanism is asymmetric versus the bringup and
     teardown.  This is mostly caused by the notifier mechanism.

   - Largely undocumented dependencies

     While some notifiers use explicitely defined notifier priorities,
     we have quite some notifiers which use numerical priorities to
     express dependencies without any documentation why.

   - Control processor driven

     Most of the bringup/teardown of a cpu is driven by a control
     processor.  While it is understandable, that preperatory steps,
     like idle thread creation, memory allocation for and initialization
     of essential facilities needs to be done before a cpu can boot,
     there is no reason why everything else must run on a control
     processor.  Before this patch series, bringup looks like this:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu

       bring the rest up

   - All or nothing approach

     There is no way to do partial bringups.  That's something which is
     really desired because we waste e.g.  at boot substantial amount of
     time just busy waiting that the cpu comes to life.  That's stupid
     as we could very well do preparatory steps and the initial IPI for
     other cpus and then go back and do the necessary low level
     synchronization with the freshly booted cpu.

   - Minimal debuggability

     Due to the notifier based design, it's impossible to switch between
     two stages of the bringup/teardown back and forth in order to test
     the correctness.  So in many hotplug notifiers the cancel
     mechanisms are either not existant or completely untested.

   - Notifier [un]registering is tedious

     To [un]register notifiers we need to protect against hotplug at
     every callsite.  There is no mechanism that bringup/teardown
     callbacks are issued on the online cpus, so every caller needs to
     do it itself.  That also includes error rollback.

  What's the new design?

     The base of the new design is a symmetric state machine, where both
     the control processor and the booting/dying cpu execute a well
     defined set of states.  Each state is symmetric in the end, except
     for some well defined exceptions, and the bringup/teardown can be
     stopped and reversed at almost all states.

     So the bringup of a cpu will look like this in the future:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu

                                       bring itself up

     The synchronization step does not require the control cpu to wait.
     That mechanism can be done asynchronously via a worker or some
     other mechanism.

     The teardown can be made very similar, so that the dying cpu cleans
     up and brings itself down.  Cleanups which need to be done after
     the cpu is gone, can be scheduled asynchronously as well.

  There is a long way to this, as we need to refactor the notion when a
  cpu is available.  Today we set the cpu online right after it comes
  out of the low level bringup, which is not really correct.

  The proper mechanism is to set it to available, i.e. cpu local
  threads, like softirqd, hotplug thread etc. can be scheduled on that
  cpu, and once it finished all booting steps, it's set to online, so
  general workloads can be scheduled on it.  The reverse happens on
  teardown.  First thing to do is to forbid scheduling of general
  workloads, then teardown all the per cpu resources and finally shut it
  off completely.

  This patch series implements the basic infrastructure for this at the
  core level.  This includes the following:

   - Basic state machine implementation with well defined states, so
     ordering and prioritization can be expressed.

   - Interfaces to [un]register state callbacks

     This invokes the bringup/teardown callback on all online cpus with
     the proper protection in place and [un]installs the callbacks in
     the state machine array.

     For callbacks which have no particular ordering requirement we have
     a dynamic state space, so that drivers don't have to register an
     explicit hotplug state.

     If a callback fails, the code automatically does a rollback to the
     previous state.

   - Sysfs interface to drive the state machine to a particular step.

     This is only partially functional today.  Full functionality and
     therefor testability will be achieved once we converted all
     existing hotplug notifiers over to the new scheme.

   - Run all CPU_ONLINE/DOWN_PREPARE notifiers on the booting/dying
     processor:

       Control CPU                     Booting CPU

       do preparatory steps
       kick cpu into life

                                       do low level init

       sync with booting cpu           sync with control cpu
       wait for boot
                                       bring itself up

                                       Signal completion to control cpu

     In a previous step of this work we've done a full tree mechanical
     conversion of all hotplug notifiers to the new scheme.  The balance
     is a net removal of about 4000 lines of code.

     This is not included in this series, as we decided to take a
     different approach.  Instead of mechanically converting everything
     over, we will do a proper overhaul of the usage sites one by one so
     they nicely fit into the symmetric callback scheme.

     I decided to do that after I looked at the ugliness of some of the
     converted sites and figured out that their hotplug mechanism is
     completely buggered anyway.  So there is no point to do a
     mechanical conversion first as we need to go through the usage
     sites one by one again in order to achieve a full symmetric and
     testable behaviour"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  cpu/hotplug: Document states better
  cpu/hotplug: Fix smpboot thread ordering
  cpu/hotplug: Remove redundant state check
  cpu/hotplug: Plug death reporting race
  rcu: Make CPU_DYING_IDLE an explicit call
  cpu/hotplug: Make wait for dead cpu completion based
  cpu/hotplug: Let upcoming cpu bring itself fully up
  arch/hotplug: Call into idle with a proper state
  cpu/hotplug: Move online calls to hotplugged cpu
  cpu/hotplug: Create hotplug threads
  cpu/hotplug: Split out the state walk into functions
  cpu/hotplug: Unpark smpboot threads from the state machine
  cpu/hotplug: Move scheduler cpu_online notifier to hotplug core
  cpu/hotplug: Implement setup/removal interface
  cpu/hotplug: Make target state writeable
  cpu/hotplug: Add sysfs state interface
  cpu/hotplug: Hand in target state to _cpu_up/down
  cpu/hotplug: Convert the hotplugged cpu work to a state machine
  cpu/hotplug: Convert to a state machine for the control processor
  cpu/hotplug: Add tracepoints
  ...
2016-03-15 13:50:29 -07:00
Bjorn Helgaas
18e5e6913b Merge branches 'pci/aer', 'pci/enumeration', 'pci/kconfig', 'pci/misc', 'pci/virtualization' and 'pci/vpd' into next
* pci/aer:
  PCI/AER: Log aer_inject error injections
  PCI/AER: Log actual error causes in aer_inject
  PCI/AER: Use dev_warn() in aer_inject
  PCI/AER: Fix aer_inject error codes

* pci/enumeration:
  PCI: Fix broken URL for Dell biosdevname

* pci/kconfig:
  PCI: Cleanup pci/pcie/Kconfig whitespace
  PCI: Include pci/hotplug Kconfig directly from pci/Kconfig
  PCI: Include pci/pcie/Kconfig directly from pci/Kconfig

* pci/misc:
  PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition
  PCI: Add QEMU top-level IDs for (sub)vendor & device
  unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition
  PCI: Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h
  PCI: Move pci_dma_* helpers to common code
  frv/PCI: Remove stray pci_{alloc,free}_consistent() declaration

* pci/virtualization:
  PCI: Wait for up to 1000ms after FLR reset
  PCI: Support SR-IOV on any function type

* pci/vpd:
  PCI: Prevent VPD access for buggy devices
  PCI: Sleep rather than busy-wait for VPD access completion
  PCI: Fold struct pci_vpd_pci22 into struct pci_vpd
  PCI: Rename VPD symbols to remove unnecessary "pci22"
  PCI: Remove struct pci_vpd_ops.release function pointer
  PCI: Move pci_vpd_release() from header file to pci/access.c
  PCI: Move pci_read_vpd() and pci_write_vpd() close to other VPD code
  PCI: Determine actual VPD size on first access
  PCI: Use bitfield instead of bool for struct pci_vpd_pci22.busy
  PCI: Allow access to VPD attributes with size 0
  PCI: Update VPD definitions
2016-03-15 08:55:02 -05:00
Linus Torvalds
d4e796152a Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle are:

   - Make schedstats a runtime tunable (disabled by default) and
     optimize it via static keys.

     As most distributions enable CONFIG_SCHEDSTATS=y due to its
     instrumentation value, this is a nice performance enhancement.
     (Mel Gorman)

   - Implement 'simple waitqueues' (swait): these are just pure
     waitqueues without any of the more complex features of full-blown
     waitqueues (callbacks, wake flags, wake keys, etc.).  Simple
     waitqueues have less memory overhead and are faster.

     Use simple waitqueues in the RCU code (in 4 different places) and
     for handling KVM vCPU wakeups.

     (Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker,
     Marcelo Tosatti)

   - sched/numa enhancements (Rik van Riel)

   - NOHZ performance enhancements (Rik van Riel)

   - Various sched/deadline enhancements (Steven Rostedt)

   - Various fixes (Peter Zijlstra)

   - ... and a number of other fixes, cleanups and smaller enhancements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits)
  sched/cputime: Fix steal_account_process_tick() to always return jiffies
  sched/deadline: Remove dl_new from struct sched_dl_entity
  Revert "kbuild: Add option to turn incompatible pointer check into error"
  sched/deadline: Remove superfluous call to switched_to_dl()
  sched/debug: Fix preempt_disable_ip recording for preempt_disable()
  sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity
  time, acct: Drop irq save & restore from __acct_update_integrals()
  acct, time: Change indentation in __acct_update_integrals()
  sched, time: Remove non-power-of-two divides from __acct_update_integrals()
  sched/rt: Kick RT bandwidth timer immediately on start up
  sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug
  sched/debug: Move sched_domain_sysctl to debug.c
  sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c
  sched/rt: Fix PI handling vs. sched_setscheduler()
  sched/core: Remove duplicated sched_group_set_shares() prototype
  sched/fair: Consolidate nohz CPU load update code
  sched/fair: Avoid using decay_load_missed() with a negative value
  sched/deadline: Always calculate end of period on sched_yield()
  sched/cgroup: Fix cgroup entity load tracking tear-down
  rcu: Use simple wait queues where possible in rcutree
  ...
2016-03-14 19:14:06 -07:00
Linus Torvalds
fbed0bc091 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking changes from Ingo Molnar:
 "Various updates:

   - Futex scalability improvements: remove page lock use for shared
     futex get_futex_key(), which speeds up 'perf bench futex hash'
     benchmarks by over 40% on a 60-core Westmere.  This makes anon-mem
     shared futexes perform close to private futexes.  (Mel Gorman)

   - lockdep hash collision detection and fix (Alfredo Alvarez
     Fernandez)

   - lockdep testing enhancements (Alfredo Alvarez Fernandez)

   - robustify lockdep init by using hlists (Andrew Morton, Andrey
     Ryabinin)

   - mutex and csd_lock micro-optimizations (Davidlohr Bueso)

   - small x86 barriers tweaks (Michael S Tsirkin)

   - qspinlock updates (Waiman Long)"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  locking/csd_lock: Use smp_cond_acquire() in csd_lock_wait()
  locking/csd_lock: Explicitly inline csd_lock*() helpers
  futex: Replace barrier() in unqueue_me() with READ_ONCE()
  locking/lockdep: Detect chain_key collisions
  locking/lockdep: Prevent chain_key collisions
  tools/lib/lockdep: Fix link creation warning
  tools/lib/lockdep: Add tests for AA and ABBA locking
  tools/lib/lockdep: Add userspace version of READ_ONCE()
  tools/lib/lockdep: Fix the build on recent kernels
  locking/qspinlock: Move __ARCH_SPIN_LOCK_UNLOCKED to qspinlock_types.h
  locking/mutex: Allow next waiter lockless wakeup
  locking/pvqspinlock: Enable slowpath locking count tracking
  locking/qspinlock: Use smp_cond_acquire() in pending code
  locking/pvqspinlock: Move lock stealing count tracking code into pv_queued_spin_steal_lock()
  locking/mcs: Fix mcs_spin_lock() ordering
  futex: Remove requirement for lock_page() in get_futex_key()
  futex: Rename barrier references in ordering guarantees
  locking/atomics: Update comment about READ_ONCE() and structures
  locking/lockdep: Eliminate lockdep_init()
  locking/lockdep: Convert hash tables to hlists
  ...
2016-03-14 15:50:44 -07:00
Linus Torvalds
d37a14bb5f Merge branch 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull ram resource handling changes from Ingo Molnar:
 "Core kernel resource handling changes to support NVDIMM error
  injection.

  This tree introduces a new I/O resource type, IORESOURCE_SYSTEM_RAM,
  for System RAM while keeping the current IORESOURCE_MEM type bit set
  for all memory-mapped ranges (including System RAM) for backward
  compatibility.

  With this resource flag it no longer takes a strcmp() loop through the
  resource tree to find "System RAM" resources.

  The new resource type is then used to extend ACPI/APEI error injection
  facility to also support NVDIMM"

* 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ACPI/EINJ: Allow memory error injection to NVDIMM
  resource: Kill walk_iomem_res()
  x86/kexec: Remove walk_iomem_res() call with GART type
  x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search
  resource: Add walk_iomem_res_desc()
  memremap: Change region_intersects() to take @flags and @desc
  arm/samsung: Change s3c_pm_run_res() to use System RAM type
  resource: Change walk_system_ram() to use System RAM type
  drivers: Initialize resource entry to zero
  xen, mm: Set IORESOURCE_SYSTEM_RAM to System RAM
  kexec: Set IORESOURCE_SYSTEM_RAM for System RAM
  arch: Set IORESOURCE_SYSTEM_RAM flag for System RAM
  ia64: Set System RAM type and descriptor
  x86/e820: Set System RAM type and descriptor
  resource: Add I/O resource descriptor
  resource: Handle resource flags properly
  resource: Add System RAM resource type
2016-03-14 15:15:51 -07:00
Sebastian Ott
80c544ded2 s390/pci: enforce fmb page boundary rule
The function measurement block must not cross a page boundary. Ensure
that by raising the alignment requirement to the smallest power of 2
larger than the size of the fmb.

Fixes: d0b088531 ("s390/pci: performance statistics and debug infrastructure")
Cc: stable@vger.kernel.org # v3.8+
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-14 16:19:09 +01:00
Alexander Duyck
01cfbad79a ipv4: Update parameters for csum_tcpudp_magic to their original types
This patch updates all instances of csum_tcpudp_magic and
csum_tcpudp_nofold to reflect the types that are usually used as the source
inputs.  For example the protocol field is populated based on nexthdr which
is actually an unsigned 8 bit value.  The length is usually populated based
on skb->len which is an unsigned integer.

This addresses an issue in which the IPv6 function csum_ipv6_magic was
generating a checksum using the full 32b of skb->len while
csum_tcpudp_magic was only using the lower 16 bits.  As a result we could
run into issues when attempting to adjust the checksum as there was no
protocol agnostic way to update it.

With this change the value is still truncated as many architectures use
"(len + proto) << 8", however this truncation only occurs for values
greater than 16776960 in length and as such is unlikely to occur as we stop
the inner headers at ~64K in size.

I did have to make a few minor changes in the arm, mn10300, nios2, and
score versions of the function in order to support these changes as they
were either using things such as an OR to combine the protocol and length,
or were using ntohs to convert the length which would have truncated the
value.

I also updated a few spots in terms of whitespace and type differences for
the addresses.  Most of this was just to make sure all of the definitions
were in sync going forward.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-13 23:55:13 -04:00
Linus Torvalds
f2c1242194 A few simple fixes for ARM, x86, PPC and generic code. The x86 MMU fix
is a bit larger because the surrounding code needed a cleanup, but
 nothing worrisome.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "A few simple fixes for ARM, x86, PPC and generic code.

  The x86 MMU fix is a bit larger because the surrounding code needed a
  cleanup, but nothing worrisome"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: MMU: fix reserved bit check for ept=0/CR0.WP=0/CR4.SMEP=1/EFER.NX=0
  KVM: MMU: fix ept=0/pte.u=1/pte.w=0/CR0.WP=0/CR4.SMEP=1/EFER.NX=0 combo
  kvm: cap halt polling at exactly halt_poll_ns
  KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS
  KVM: VMX: disable PEBS before a guest entry
  KVM: PPC: Book3S HV: Sanitize special-purpose register values on guest exit
2016-03-10 10:42:15 -08:00
Paolo Bonzini
f958ee745f KVM: s390: Fixes and features for kvm/next (4.6) part 2
- add watchdog diagnose to trace event decoder
 - better handle the cpu timer when not inside the guest
 - only provide STFLE if the CPU model has STFLE
 - reduce DMA page usage
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Merge tag 'kvm-s390-next-4.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD

KVM: s390: Fixes and features for kvm/next (4.6) part 2

- add watchdog diagnose to trace event decoder
- better handle the cpu timer when not inside the guest
- only provide STFLE if the CPU model has STFLE
- reduce DMA page usage
2016-03-10 17:06:07 +01:00
Martin Schwidefsky
e370e47694 s390: fix floating pointer register corruption (again)
There is a tricky interaction between the machine check handler
and the critical sections of load_fpu_regs and save_fpu_regs
functions. If the machine check interrupts one of the two
functions the critical section cleanup will complete the function
before the machine check handler s390_do_machine_check is called.
Trouble is that the machine check handler needs to validate the
floating point registers *before* and not *after* the completion
of load_fpu_regs/save_fpu_regs.

The simplest solution is to rewind the PSW to the start of the
load_fpu_regs/save_fpu_regs and retry the function after the
return from the machine check handler.

Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: <stable@vger.kernel.org> # 4.3+
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-10 14:35:42 +01:00
Heiko Carstens
8f100bb1ff s390/cpumf: add missing lpp magic initialization
Add the missing lpp magic initialization for cpu 0. Without this all
samples on cpu 0 do not have the most significant bit set in the
program parameter field, which we use to distinguish between guest and
host samples if the pid is also 0.

We did initialize the lpp magic in the absolute zero lowcore but
forgot that when switching to the allocated lowcore on cpu 0 only.

Reported-by: Shu Juan Zhang <zhshuj@cn.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-10 14:35:35 +01:00
Martin Schwidefsky
3446c13b26 s390/mm: four page table levels vs. fork
The fork of a process with four page table levels is broken since
git commit 6252d702c5311ce9 "[S390] dynamic page tables."

All new mm contexts are created with three page table levels and
an asce limit of 4TB. If the parent has four levels dup_mmap will
add vmas to the new context which are outside of the asce limit.
The subsequent call to copy_page_range will walk the three level
page table structure of the new process with non-zero pgd and pud
indexes. This leads to memory clobbers as the pgd_index *and* the
pud_index is added to the mm->pgd pointer without a pgd_deref
in between.

The init_new_context() function is selecting the number of page
table levels for a new context. The function is used by mm_init()
which in turn is called by dup_mm() and mm_alloc(). These two are
used by fork() and exec(). The init_new_context() function can
distinguish the two cases by looking at mm->context.asce_limit,
for fork() the mm struct has been copied and the number of page
table levels may not change. For exec() the mm_alloc() function
set the new mm structure to zero, in this case a three-level page
table is created as the temporary stack space is located at
STACK_TOP_MAX = 4TB.

This fixes CVE-2016-2143.

Reported-by: Marcin Kościelnicki <koriakin@0x04.net>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-10 09:21:24 +01:00
Paolo Bonzini
ab92f30875 KVM/ARM updates for 4.6
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
 - PMU support for guests
 - 32bit world switch rewritten in C
 - Various optimizations to the vgic save/restore code
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Merge tag 'kvm-arm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/ARM updates for 4.6

- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- Various optimizations to the vgic save/restore code

Conflicts:
	include/uapi/linux/kvm.h
2016-03-09 11:50:42 +01:00
Bjorn Helgaas
e7e127e3c7 PCI: Include pci/hotplug Kconfig directly from pci/Kconfig
Include pci/hotplug/Kconfig directly from pci/Kconfig, so arches don't
have to source both pci/Kconfig and pci/hotplug/Kconfig.

Note that this effectively adds pci/hotplug/Kconfig to the following
arches, because they already sourced drivers/pci/Kconfig but they
previously did not source drivers/pci/hotplug/Kconfig:

  alpha
  arm
  avr32
  frv
  m68k
  microblaze
  mn10300
  sparc
  unicore32

Inspired-by-patch-from: Bogicevic Sasa <brutallesale@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-03-08 15:10:48 -06:00
Bogicevic Sasa
5f8fc43217 PCI: Include pci/pcie/Kconfig directly from pci/Kconfig
Include pci/pcie/Kconfig directly from pci/Kconfig, so arches don't
have to source both pci/Kconfig and pci/pcie/Kconfig.

Note that this effectively adds pci/pcie/Kconfig to the following
arches, because they already sourced drivers/pci/Kconfig but they
previously did not source drivers/pci/pcie/Kconfig:

  alpha
  avr32
  blackfin
  frv
  m32r
  m68k
  microblaze
  mn10300
  parisc
  sparc
  unicore32
  xtensa

[bhelgaas: changelog, source pci/pcie/Kconfig at top of pci/Kconfig, whitespace]
Signed-off-by: Sasa Bogicevic <brutallesale@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-03-08 14:36:48 -06:00
David S. Miller
810813c47a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, as well as one instance
(vxlan) of a bug fix in 'net' overlapping with code movement
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08 12:34:12 -05:00
Adam Buchbinder
7eb792bf7c s390: Fix misspellings in comments
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:17 +01:00
Martin Schwidefsky
1e133ab296 s390/mm: split arch/s390/mm/pgtable.c
The pgtable.c file is quite big, before it grows any larger split it
into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related
header definitions into the new gmap.h header and all of the pgste
helpers from pgtable.h to pgtable.c.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:15 +01:00
Martin Schwidefsky
227be799c3 s390/mm: uninline pmdp_xxx functions from pgtable.h
The pmdp_xxx function are smaller than their ptep_xxx counterparts
but to keep things symmetrical unline them as well.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:14 +01:00
Martin Schwidefsky
ebde765c0e s390/mm: uninline ptep_xxx functions from pgtable.h
The code in the various ptep_xxx functions has grown quite large,
consolidate them to four out-of-line functions:
  ptep_xchg_direct to exchange a pte with another with immediate flushing
  ptep_xchg_lazy to exchange a pte with another in a batched update
  ptep_modify_prot_start to begin a protection flags update
  ptep_modify_prot_commit to commit a protection flags update

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 15:00:12 +01:00
David Hildenbrand
c54f0d6ae0 KVM: s390: allocate only one DMA page per VM
We can fit the 2k for the STFLE interpretation and the crypto
control block into one DMA page. As we now only have to allocate
one DMA page, we can clean up the code a bit.

As a nice side effect, this also fixes a problem with crycbd alignment in
case special allocation debug options are enabled, debugged by Sascha
Silbe.

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:54 +01:00
David Hildenbrand
80bc79dc0b KVM: s390: enable STFLE interpretation only if enabled for the guest
Not setting the facility list designation disables STFLE interpretation,
this is what we want if the guest was told to not have it.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:54 +01:00
David Hildenbrand
b3c17f10fa KVM: s390: wake up when the VCPU cpu timer expires
When the VCPU cpu timer expires, we have to wake up just like when the ckc
triggers. For now, setting up a cpu timer in the guest and going into
enabled wait will never lead to a wakeup. This patch fixes this problem.
Just as for the ckc, we have to take care of waking up too early. We
have to recalculate the sleep time and go back to sleep.

Please note that the timer callback calls kvm_s390_get_cpu_timer() from
interrupt context. As the timer is canceled when leaving handle_wait(),
and we don't do any VCPU cpu timer writes/updates in that function, we can
be sure that we will never try to read the VCPU cpu timer from the same cpu
that is currentyl updating the timer (deadlock).

Reported-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Tested-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:53 +01:00
David Hildenbrand
5ebda31686 KVM: s390: step the VCPU timer while in enabled wait
The cpu timer is a mean to measure task execution time. We want
to account everything for a VCPU for which it is responsible. Therefore,
if the VCPU wants to sleep, it shall be accounted for it.

We can easily get this done by not disabling cpu timer accounting when
scheduled out while sleeping because of enabled wait.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:53 +01:00
David Hildenbrand
9c23a1318e KVM: s390: protect VCPU cpu timer with a seqcount
For now, only the owning VCPU thread (that has loaded the VCPU) can get a
consistent cpu timer value when calculating the delta. However, other
threads might also be interested in a more recent, consistent value. Of
special interest will be the timer callback of a VCPU that executes without
having the VCPU loaded and could run in parallel with the VCPU thread.

The cpu timer has a nice property: it is only updated by the owning VCPU
thread. And speaking about accounting, a consistent value can only be
calculated by looking at cputm_start and the cpu timer itself in
one shot, otherwise the result might be wrong.

As we only have one writing thread at a time (owning VCPU thread), we can
use a seqcount instead of a seqlock and retry if the VCPU refreshed its
cpu timer. This avoids any heavy locking and only introduces a counter
update/check plus a handful of smp_wmb().

The owning VCPU thread should never have to retry on reads, and also for
other threads this might be a very rare scenario.

Please note that we have to use the raw_* variants for locking the seqcount
as lockdep will produce false warnings otherwise. The rq->lock held during
vcpu_load/put is also acquired from hardirq context. Lockdep cannot know
that we avoid potential deadlocks by disabling preemption and thereby
disable concurrent write locking attempts (via vcpu_put/load).

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:53 +01:00
David Hildenbrand
db0758b297 KVM: s390: step VCPU cpu timer during kvm_run ioctl
Architecturally we should only provide steal time if we are scheduled
away, and not if the host interprets a guest exit. We have to step
the guest CPU timer in these cases.

In the first shot, we will step the VCPU timer only during the kvm_run
ioctl. Therefore all time spent e.g. in interception handlers or on irq
delivery will be accounted for that VCPU.

We have to take care of a few special cases:
- Other VCPUs can test for pending irqs. We can only report a consistent
  value for the VCPU thread itself when adding the delta.
- We have to take care of STP sync, therefore we have to extend
  kvm_clock_sync() and disable preemption accordingly
- During any call to disable/enable/start/stop we could get premeempted
  and therefore get start/stop calls. Therefore we have to make sure we
  don't get into an inconsistent state.

Whenever a VCPU is scheduled out, sleeping, in user space or just about
to enter the SIE, the guest cpu timer isn't stepped.

Please note that all primitives are prepared to be called from both
environments (cpu timer accounting enabled or not), although not completely
used in this patch yet (e.g. kvm_s390_set_cpu_timer() will never be called
while cpu timer accounting is enabled).

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:52 +01:00
David Hildenbrand
4287f247f6 KVM: s390: abstract access to the VCPU cpu timer
We want to manually step the cpu timer in certain scenarios in the future.
Let's abstract any access to the cpu timer, so we can hide the complexity
internally.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:52 +01:00
David Hildenbrand
01a745ac8b KVM: s390: store cpu id in vcpu->cpu when scheduled in
By storing the cpu id, we have a way to verify if the current cpu is
owning a VCPU.

Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:51 +01:00
Alexander Yarygin
dce382b6c7 KVM: s390: Add diag "watchdog functions" to trace event decoding
DIAG 0x288 may occur now. Let's add its code to the diag table in
sie.h.

Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 13:57:51 +01:00
David Hildenbrand
9522b37f5a KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUS
With MACHINE_HAS_VX, we convert the floating point registers from the
vector registeres when storing the status. For other VCPUs, these are
stored to vcpu->run->s.regs.vrs, but we are using current->thread.fpu.vxrs,
which resolves to the currently loaded VCPU.

So kvm_s390_store_status_unloaded() currently writes the wrong floating
point registers (converted from the vector registers) when called from
another VCPU on a z13.

This is only the case for old user space not handling SIGP STORE STATUS and
SIGP STOP AND STORE STATUS, but relying on the kernel implementation. All
other calls come from the loaded VCPU via kvm_s390_store_status().

Fixes: 9abc2a08a7d6 (KVM: s390: fix memory overwrites when vx is disabled)
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # v4.4+
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-08 12:47:01 +01:00
Christian Borntraeger
7a76aa95f6 s390/cpumf: Fix lpp detection
we have to check bit 40 of the facility list before issuing LPP
and not bit 48. Otherwise a guest running on a system with
"The decimal-floating-point zoned-conversion facility" and without
the "The set-program-parameters facility" might crash on an lpp
instruction.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # v4.4+
Fixes: e22cf8ca6f75 ("s390/cpumf: rework program parameter setting to detect guest samples")
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 10:38:06 +01:00
Christoph Hellwig
bc4b024a8b PCI: Move pci_dma_* helpers to common code
For a long time all architectures implement the pci_dma_* functions using
the generic DMA API, and they all use the same header to do so.

Move this header, pci-dma-compat.h, to include/linux and include it from
the generic pci.h instead of having each arch duplicate this include.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-03-07 10:40:02 -06:00
Martin Schwidefsky
988b86e69d s390/pci: add ioctl interface for CLP
Provide a user space interface to issue call logical-processor instructions.
Only selected CLP commands are allowed, enough to get the full overview of
the installed PCI functions.

Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-07 16:54:32 +01:00
Joe Perches
baebc70a4d s390: Use pr_warn instead of pr_warning
Convert the uses of pr_warning to pr_warn so there are fewer
uses of the old pr_warning.

Miscellanea:

o Align arguments
o Coalesce formats

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-07 13:12:04 +01:00
Jiri Kosina
335e073faa klp: remove CONFIG_LIVEPATCH dependency from klp headers
There is no need for livepatch.h (generic and arch-specific) to depend
on CONFIG_LIVEPATCH. Remove that superfluous dependency.

Reported-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-03-06 22:22:10 +01:00
Miroslav Benes
b24b78a113 klp: remove superfluous errors in asm/livepatch.h
There is an #error in asm/livepatch.h for both x86 and s390 in
!CONFIG_LIVEPATCH cases. It does not make much sense as pointed out by
Michael Ellerman. One can happily include asm/livepatch.h with
CONFIG_LIVEPATCH. Remove it as useless.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-03-06 22:19:26 +01:00
Ingo Molnar
bc94b99636 Linux 4.5-rc6
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Merge tag 'v4.5-rc6' into core/resources, to resolve conflict

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-04 12:12:08 +01:00
Christian Borntraeger
e82becfc18 s390/dma: Allow per device dma ops
As virtio-ccw will have dma ops, we can no longer default to the
zPCI ones. Make use of dev_archdata to keep the dma_ops per device.
The pci devices now use that to override the default, and the
default is changed to use the noop ops for everything that does not
specify a device specific one.
To compile without PCI support we will enable HAS_DMA all the time,
via the default config in lib/Kconfig.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02 17:01:56 +02:00
Heiko Carstens
f369b98ee3 s390/percpu: remove this_cpu_cmpxchg_double_4
git commit 26f15caaf993 ("s390/cmpxchg: simplify cmpxchg_double")
removed support for cmpxchg_double for two consecutive four byte
values, for which it would generate a cds instruction.

However I forgot to remove the corresponding define in our percpu
header file, which means that this_cpu_cmpxchg_double would now
incorrectly generate a cdsg instruction if being used on a double four
byte location. Therefore remove the percpu define as well.

There is currently no user and therefore no bug fixed with
this. Obviously any such user could and should simply use cmpxchg.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-02 06:44:30 -06:00
Christian Borntraeger
b1685ab9bd s390/cpumf: Improve guest detection heuristics
commit e22cf8ca6f75 ("s390/cpumf: rework program parameter setting
to detect guest samples") requires guest changes to get proper
guest/host. We can do better: We can use the primary asn value,
which is set on all Linux variants to compare this with the host
pp value.
We now have the following cases:
1. Guest using PP
host sample:  gpp == 0, asn == hpp --> host
guest sample: gpp != 0 --> guest
2. Guest not using PP
host sample:  gpp == 0, asn == hpp --> host
guest sample: gpp == 0, asn != hpp --> guest

As soon as the host no longer sets CR4, we must back out
this heuristics - let's add a comment in switch_to.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-02 06:44:28 -06:00
Heiko Carstens
5d7eccecf8 s390/fault: merge report_user_fault implementations
We have two close to identical report_user_fault functions.
Add a parameter to one and get rid of the other one in order
to reduce code duplication.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-02 06:44:27 -06:00
Heiko Carstens
ee8479bb97 s390/dis: use correct escape sequence for '%' character
The double escape character sequence introduced with commit
272fa59ccb4f ("s390/dis: Fix handling of format specifiers") is not
necessary anymore since commit 561e10300269 ("s390/dis: Fix printing
of the register numbers").

Instead this now generates an extra '%' character:

lg      %%r1,160(%%r11)

So fix this and basically revert 272fa59ccb4f.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-02 06:44:25 -06:00
Martin Schwidefsky
443a813304 s390/kvm: simplify set_guest_storage_key
Git commit ab3f285f227fec62868037e9b1b1fd18294a83b8
"KVM: s390/mm: try a cow on read only pages for key ops"
added a fixup_user_fault to set_guest_storage_key force a copy on
write if the page is mapped read-only. This is supposed to fix the
problem of differing storage keys for shared mappings, e.g. the
empty_zero_page.
But if the storage key is set before the pte is mapped the storage
key update is done on the pgste. A later fault will happily map the
shared page with the key from the pgste.

Eventually git commit 2faee8ff9dc6f4bfe46f6d2d110add858140fb20
"s390/mm: prevent and break zero page mappings in case of storage keys"
fixed this problem for the empty_zero_page. The commit makes sure that
guests enabled for storage keys will not use the empty_zero_page at all.

As the call to fixup_user_fault in set_guest_storage_key depends on the
order of the storage key operation vs. the fault that maps the pte
it does not really fix anything. Just remove it.

Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-02 06:44:22 -06:00
Thomas Gleixner
fc6d73d674 arch/hotplug: Call into idle with a proper state
Let the non boot cpus call into idle with the corresponding hotplug state, so
the hotplug core can handle the further bringup. That's a first step to
convert the boot side of the hotplugged cpus to do all the synchronization
with the other side through the state machine. For now it'll only start the
hotplug thread and kick the full bringup of the cpu.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel <riel@redhat.com>
Cc: Rafael Wysocki <rafael.j.wysocki@intel.com>
Cc: "Srivatsa S. Bhat" <srivatsa@mit.edu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-01 20:36:57 +01:00
Ingo Molnar
39a1142dbb Linux 4.5-rc6
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Merge tag 'v4.5-rc6' into locking/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29 09:55:22 +01:00
Ingo Molnar
6aa447bcbb Merge branch 'sched/urgent' into sched/core, to pick up fixes before applying new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29 09:42:07 +01:00
Tom Herbert
a87cb3e48e net: Facility to report route quality of connected sockets
This patch add the SO_CNX_ADVICE socket option (setsockopt only). The
purpose is to allow an application to give feedback to the kernel about
the quality of the network path for a connected socket. The value
argument indicates the type of quality report. For this initial patch
the only supported advice is a value of 1 which indicates "bad path,
please reroute"-- the action taken by the kernel is to call
dst_negative_advice which will attempt to choose a different ECMP route,
reset the TX hash for flow label and UDP source port in encapsulation,
etc.

This facility should be useful for connected UDP sockets where only the
application can provide any feedback about path quality. It could also
be useful for TCP applications that have additional knowledge about the
path outside of the normal TCP control loop.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-25 22:01:22 -05:00
Marcelo Tosatti
8577370fb0 KVM: Use simple waitqueue for vcpu->wq
The problem:

On -rt, an emulated LAPIC timer instances has the following path:

1) hard interrupt
2) ksoftirqd is scheduled
3) ksoftirqd wakes up vcpu thread
4) vcpu thread is scheduled

This extra context switch introduces unnecessary latency in the
LAPIC path for a KVM guest.

The solution:

Allow waking up vcpu thread from hardirq context,
thus avoiding the need for ksoftirqd to be scheduled.

Normal waitqueues make use of spinlocks, which on -RT
are sleepable locks. Therefore, waking up a waitqueue
waiter involves locking a sleeping lock, which
is not allowed from hard interrupt context.

cyclictest command line:

This patch reduces the average latency in my tests from 14us to 11us.

Daniel writes:
Paolo asked for numbers from kvm-unit-tests/tscdeadline_latency
benchmark on mainline. The test was run 1000 times on
tip/sched/core 4.4.0-rc8-01134-g0905f04:

  ./x86-run x86/tscdeadline_latency.flat -cpu host

with idle=poll.

The test seems not to deliver really stable numbers though most of
them are smaller. Paolo write:

"Anything above ~10000 cycles means that the host went to C1 or
lower---the number means more or less nothing in that case.

The mean shows an improvement indeed."

Before:

               min             max         mean           std
count  1000.000000     1000.000000  1000.000000   1000.000000
mean   5162.596000  2019270.084000  5824.491541  20681.645558
std      75.431231   622607.723969    89.575700   6492.272062
min    4466.000000    23928.000000  5537.926500    585.864966
25%    5163.000000  1613252.750000  5790.132275  16683.745433
50%    5175.000000  2281919.000000  5834.654000  23151.990026
75%    5190.000000  2382865.750000  5861.412950  24148.206168
max    5228.000000  4175158.000000  6254.827300  46481.048691

After
               min            max         mean           std
count  1000.000000     1000.00000  1000.000000   1000.000000
mean   5143.511000  2076886.10300  5813.312474  21207.357565
std      77.668322   610413.09583    86.541500   6331.915127
min    4427.000000    25103.00000  5529.756600    559.187707
25%    5148.000000  1691272.75000  5784.889825  17473.518244
50%    5160.000000  2308328.50000  5832.025000  23464.837068
75%    5172.000000  2393037.75000  5853.177675  24223.969976
max    5222.000000  3922458.00000  6186.720500  42520.379830

[Patch was originaly based on the swait implementation found in the -rt
 tree. Daniel ported it to mainline's version and gathered the
 benchmark numbers for tscdeadline_latency test.]

Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: linux-rt-users@vger.kernel.org
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1455871601-27484-4-git-send-email-wagi@monom.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25 11:27:16 +01:00
Heiko Carstens
993e068108 s390/oprofile: add z13/z13s model numbers
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-24 12:18:10 +01:00
Heiko Carstens
bb3aa61401 s390: add z13s model number to z13 elf platform
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-24 12:18:07 +01:00