<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/arm/kernel, branch v4.6-rc2</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections</title>
<updated>2016-03-25T23:37:42+00:00</updated>
<author>
<name>Alexander Potapenko</name>
<email>glider@google.com</email>
</author>
<published>2016-03-25T21:22:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=be7635e7287e0e8013af3c89a6354a9e0182594c'/>
<id>be7635e7287e0e8013af3c89a6354a9e0182594c</id>
<content type='text'>
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to &lt;linux/interrupt.h&gt; so that the
users don't need to pull in &lt;linux/ftrace.h&gt;.  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko &lt;glider@google.com&gt;
Acked-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Pekka Enberg &lt;penberg@kernel.org&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Cc: Andrey Konovalov &lt;adech.fo@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Konstantin Serebryany &lt;kcc@google.com&gt;
Cc: Dmitry Chernenkov &lt;dmitryc@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to &lt;linux/interrupt.h&gt; so that the
users don't need to pull in &lt;linux/ftrace.h&gt;.  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko &lt;glider@google.com&gt;
Acked-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Christoph Lameter &lt;cl@linux.com&gt;
Cc: Pekka Enberg &lt;penberg@kernel.org&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Cc: Joonsoo Kim &lt;iamjoonsoo.kim@lge.com&gt;
Cc: Andrey Konovalov &lt;adech.fo@gmail.com&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Andrey Ryabinin &lt;ryabinin.a.a@gmail.com&gt;
Cc: Konstantin Serebryany &lt;kcc@google.com&gt;
Cc: Dmitry Chernenkov &lt;dmitryc@google.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'arm64-perf' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux</title>
<updated>2016-03-21T20:14:16+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-03-21T20:14:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c856e14dad8cb1b085ae1f30c5e125c6d46019b'/>
<id>2c856e14dad8cb1b085ae1f30c5e125c6d46019b</id>
<content type='text'>
Pull arm[64] perf updates from Will Deacon:
 "I have another mixed bag of ARM-related perf patches here.

  It's about 25% CPU and 75% interconnect, but with drivers/bus/
  languishing without an obvious maintainer or tree, Olof and I agreed
  to keep all of these PMU patches together.  I suspect a whole load of
  code from drivers/bus/arm-* can be moved under drivers/perf/, so
  that's on the radar for the future.

  Summary:

   - Initial support for ARMv8.1 CPU PMUs

   - Support for the CPU PMU in Cavium ThunderX

   - CPU PMU support for systems running 32-bit Linux in secure mode

   - Support for the system PMU in ARM CCI-550 (Cache Coherent Interconnect)"

* tag 'arm64-perf' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (26 commits)
  drivers/perf: arm_pmu: avoid NULL dereference when not using devicetree
  arm64: perf: Extend ARMV8_EVTYPE_MASK to include PMCR.LC
  arm-cci: remove unused variable
  arm-cci: don't return value from void function
  arm-cci: make private functions static
  arm-cci: CoreLink CCI-550 PMU driver
  arm-cci500: Rearrange PMU driver for code sharing with CCI-550 PMU
  arm-cci: CCI-500: Work around PMU counter writes
  arm-cci: Provide hook for writing to PMU counters
  arm-cci: Add helper to enable PMU without synchornising counters
  arm-cci: Add routines to save/restore all counters
  arm-cci: Get the status of a counter
  arm-cci: write_counter: Remove redundant check
  arm-cci: Delay PMU counter writes to pmu::pmu_enable
  arm-cci: Refactor CCI PMU enable/disable methods
  arm-cci: Group writes to counter
  arm-cci: fix handling cpumask_any_but return value
  arm-cci: simplify sysfs attr handling
  drivers/perf: arm_pmu: implement CPU_PM notifier
  arm64: dts: Add Cavium ThunderX specific PMU
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull arm[64] perf updates from Will Deacon:
 "I have another mixed bag of ARM-related perf patches here.

  It's about 25% CPU and 75% interconnect, but with drivers/bus/
  languishing without an obvious maintainer or tree, Olof and I agreed
  to keep all of these PMU patches together.  I suspect a whole load of
  code from drivers/bus/arm-* can be moved under drivers/perf/, so
  that's on the radar for the future.

  Summary:

   - Initial support for ARMv8.1 CPU PMUs

   - Support for the CPU PMU in Cavium ThunderX

   - CPU PMU support for systems running 32-bit Linux in secure mode

   - Support for the system PMU in ARM CCI-550 (Cache Coherent Interconnect)"

* tag 'arm64-perf' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (26 commits)
  drivers/perf: arm_pmu: avoid NULL dereference when not using devicetree
  arm64: perf: Extend ARMV8_EVTYPE_MASK to include PMCR.LC
  arm-cci: remove unused variable
  arm-cci: don't return value from void function
  arm-cci: make private functions static
  arm-cci: CoreLink CCI-550 PMU driver
  arm-cci500: Rearrange PMU driver for code sharing with CCI-550 PMU
  arm-cci: CCI-500: Work around PMU counter writes
  arm-cci: Provide hook for writing to PMU counters
  arm-cci: Add helper to enable PMU without synchornising counters
  arm-cci: Add routines to save/restore all counters
  arm-cci: Get the status of a counter
  arm-cci: write_counter: Remove redundant check
  arm-cci: Delay PMU counter writes to pmu::pmu_enable
  arm-cci: Refactor CCI PMU enable/disable methods
  arm-cci: Group writes to counter
  arm-cci: fix handling cpumask_any_but return value
  arm-cci: simplify sysfs attr handling
  drivers/perf: arm_pmu: implement CPU_PM notifier
  arm64: dts: Add Cavium ThunderX specific PMU
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm</title>
<updated>2016-03-19T23:31:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-03-19T23:31:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=de06dbfa7861c9019eedefc0c356ba86e5098f1b'/>
<id>de06dbfa7861c9019eedefc0c356ba86e5098f1b</id>
<content type='text'>
Pull ARM updates from Russell King:
 "Another mixture of changes this time around:

   - Split XIP linker file from main linker file to make it more
     maintainable, and various XIP fixes, and clean up a resulting
     macro.

   - Decompressor cleanups from Masahiro Yamada

   - Avoid printing an error for a missing L2 cache

   - Remove some duplicated symbols in System.map, and move
     vectors/stubs back into kernel VMA

   - Various low priority fixes from Arnd

   - Updates to allow bus match functions to return negative errno
     values, touching some drivers and the driver core.  Greg has acked
     these changes.

   - Virtualisation platform udpates form Jean-Philippe Brucker.

   - Security enhancements from Kees Cook

   - Rework some Kconfig dependencies and move PSCI idle management code
     out of arch/arm into drivers/firmware/psci.c

   - ARM DMA mapping updates, touching media, acked by Mauro.

   - Fix places in ARM code which should be using virt_to_idmap() so
     that Keystone2 can work.

   - Fix Marvell Tauros2 to work again with non-DT boots.

   - Provide a delay timer for ARM Orion platforms"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (45 commits)
  ARM: 8546/1: dma-mapping: refactor to fix coherent+cma+gfp=0
  ARM: 8547/1: dma-mapping: store buffer information
  ARM: 8543/1: decompressor: rename suffix_y to compress-y
  ARM: 8542/1: decompressor: merge piggy.*.S and simplify Makefile
  ARM: 8541/1: decompressor: drop redundant FORCE in Makefile
  ARM: 8540/1: decompressor: use clean-files instead of extra-y to clean files
  ARM: 8539/1: decompressor: drop more unneeded assignments to "targets"
  ARM: 8538/1: decompressor: drop unneeded assignments to "targets"
  ARM: 8532/1: uncompress: mark putc as inline
  ARM: 8531/1: turn init_new_context into an inline function
  ARM: 8530/1: remove VIRT_TO_BUS
  ARM: 8537/1: drop unused DEBUG_RODATA from XIP_KERNEL
  ARM: 8536/1: mm: hide __start_rodata_section_aligned for non-debug builds
  ARM: 8535/1: mm: DEBUG_RODATA makes no sense with XIP_KERNEL
  ARM: 8534/1: virt: fix hyp-stub build for pre-ARMv7 CPUs
  ARM: make the physical-relative calculation more obvious
  ARM: 8512/1: proc-v7.S: Adjust stack address when XIP_KERNEL
  ARM: 8411/1: Add default SPARSEMEM settings
  ARM: 8503/1: clk_register_clkdev: remove format string interface
  ARM: 8529/1: remove 'i' and 'zi' targets
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull ARM updates from Russell King:
 "Another mixture of changes this time around:

   - Split XIP linker file from main linker file to make it more
     maintainable, and various XIP fixes, and clean up a resulting
     macro.

   - Decompressor cleanups from Masahiro Yamada

   - Avoid printing an error for a missing L2 cache

   - Remove some duplicated symbols in System.map, and move
     vectors/stubs back into kernel VMA

   - Various low priority fixes from Arnd

   - Updates to allow bus match functions to return negative errno
     values, touching some drivers and the driver core.  Greg has acked
     these changes.

   - Virtualisation platform udpates form Jean-Philippe Brucker.

   - Security enhancements from Kees Cook

   - Rework some Kconfig dependencies and move PSCI idle management code
     out of arch/arm into drivers/firmware/psci.c

   - ARM DMA mapping updates, touching media, acked by Mauro.

   - Fix places in ARM code which should be using virt_to_idmap() so
     that Keystone2 can work.

   - Fix Marvell Tauros2 to work again with non-DT boots.

   - Provide a delay timer for ARM Orion platforms"

* 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (45 commits)
  ARM: 8546/1: dma-mapping: refactor to fix coherent+cma+gfp=0
  ARM: 8547/1: dma-mapping: store buffer information
  ARM: 8543/1: decompressor: rename suffix_y to compress-y
  ARM: 8542/1: decompressor: merge piggy.*.S and simplify Makefile
  ARM: 8541/1: decompressor: drop redundant FORCE in Makefile
  ARM: 8540/1: decompressor: use clean-files instead of extra-y to clean files
  ARM: 8539/1: decompressor: drop more unneeded assignments to "targets"
  ARM: 8538/1: decompressor: drop unneeded assignments to "targets"
  ARM: 8532/1: uncompress: mark putc as inline
  ARM: 8531/1: turn init_new_context into an inline function
  ARM: 8530/1: remove VIRT_TO_BUS
  ARM: 8537/1: drop unused DEBUG_RODATA from XIP_KERNEL
  ARM: 8536/1: mm: hide __start_rodata_section_aligned for non-debug builds
  ARM: 8535/1: mm: DEBUG_RODATA makes no sense with XIP_KERNEL
  ARM: 8534/1: virt: fix hyp-stub build for pre-ARMv7 CPUs
  ARM: make the physical-relative calculation more obvious
  ARM: 8512/1: proc-v7.S: Adjust stack address when XIP_KERNEL
  ARM: 8411/1: Add default SPARSEMEM settings
  ARM: 8503/1: clk_register_clkdev: remove format string interface
  ARM: 8529/1: remove 'i' and 'zi' targets
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2016-03-16T16:55:35+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-03-16T16:55:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=10dc3747661bea9215417b659449bb7b8ed3df2c'/>
<id>10dc3747661bea9215417b659449bb7b8ed3df2c</id>
<content type='text'>
Pull KVM updates from Paolo Bonzini:
 "One of the largest releases for KVM...  Hardly any generic
  changes, but lots of architecture-specific updates.

  ARM:
   - 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.

  PPC:
   - enabled KVM-VFIO integration ("VFIO device")
   - optimizations to speed up IPIs between vcpus
   - in-kernel handling of IOMMU hypercalls
   - support for dynamic DMA windows (DDW).

  s390:
   - provide the floating point registers via sync regs;
   - separated instruction vs.  data accesses
   - dirty log improvements for huge guests
   - bugfixes and documentation improvements.

  x86:
   - Hyper-V VMBus hypercall userspace exit
   - alternative implementation of lowest-priority interrupts using
     vector hashing (for better VT-d posted interrupt support)
   - fixed guest debugging with nested virtualizations
   - improved interrupt tracking in the in-kernel IOAPIC
   - generic infrastructure for tracking writes to guest
     memory - currently its only use is to speedup the legacy shadow
     paging (pre-EPT) case, but in the future it will be used for
     virtual GPUs as well
   - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
  KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
  KVM: x86: disable MPX if host did not enable MPX XSAVE features
  arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
  arm64: KVM: vgic-v3: Reset LRs at boot time
  arm64: KVM: vgic-v3: Do not save an LR known to be empty
  arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
  arm64: KVM: vgic-v3: Avoid accessing ICH registers
  KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
  KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
  KVM: arm/arm64: vgic-v2: Reset LRs at boot time
  KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
  KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
  KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
  KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
  KVM: s390: allocate only one DMA page per VM
  KVM: s390: enable STFLE interpretation only if enabled for the guest
  KVM: s390: wake up when the VCPU cpu timer expires
  KVM: s390: step the VCPU timer while in enabled wait
  KVM: s390: protect VCPU cpu timer with a seqcount
  KVM: s390: step VCPU cpu timer during kvm_run ioctl
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull KVM updates from Paolo Bonzini:
 "One of the largest releases for KVM...  Hardly any generic
  changes, but lots of architecture-specific updates.

  ARM:
   - 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.

  PPC:
   - enabled KVM-VFIO integration ("VFIO device")
   - optimizations to speed up IPIs between vcpus
   - in-kernel handling of IOMMU hypercalls
   - support for dynamic DMA windows (DDW).

  s390:
   - provide the floating point registers via sync regs;
   - separated instruction vs.  data accesses
   - dirty log improvements for huge guests
   - bugfixes and documentation improvements.

  x86:
   - Hyper-V VMBus hypercall userspace exit
   - alternative implementation of lowest-priority interrupts using
     vector hashing (for better VT-d posted interrupt support)
   - fixed guest debugging with nested virtualizations
   - improved interrupt tracking in the in-kernel IOAPIC
   - generic infrastructure for tracking writes to guest
     memory - currently its only use is to speedup the legacy shadow
     paging (pre-EPT) case, but in the future it will be used for
     virtual GPUs as well
   - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
  KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
  KVM: x86: disable MPX if host did not enable MPX XSAVE features
  arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
  arm64: KVM: vgic-v3: Reset LRs at boot time
  arm64: KVM: vgic-v3: Do not save an LR known to be empty
  arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
  arm64: KVM: vgic-v3: Avoid accessing ICH registers
  KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
  KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
  KVM: arm/arm64: vgic-v2: Reset LRs at boot time
  KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
  KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
  KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
  KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
  KVM: s390: allocate only one DMA page per VM
  KVM: s390: enable STFLE interpretation only if enabled for the guest
  KVM: s390: wake up when the VCPU cpu timer expires
  KVM: s390: step the VCPU timer while in enabled wait
  KVM: s390: protect VCPU cpu timer with a seqcount
  KVM: s390: step VCPU cpu timer during kvm_run ioctl
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2016-03-15T20:50:29+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-03-15T20:50:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=710d60cbf1b312a8075a2158cbfbbd9c66132dcc'/>
<id>710d60cbf1b312a8075a2158cbfbbd9c66132dcc</id>
<content type='text'>
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
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'core-resources-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2016-03-14T22:15:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-03-14T22:15:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=d37a14bb5fed13a52dada3fa9ef4488ac588b35e'/>
<id>d37a14bb5fed13a52dada3fa9ef4488ac588b35e</id>
<content type='text'>
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
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'amba', 'fixes', 'misc' and 'tauros2' into for-next</title>
<updated>2016-03-04T23:36:02+00:00</updated>
<author>
<name>Russell King</name>
<email>rmk+kernel@arm.linux.org.uk</email>
</author>
<published>2016-03-04T23:36:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=1b3bf847977c2e5974012ddd4b25fef50967d785'/>
<id>1b3bf847977c2e5974012ddd4b25fef50967d785</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>arch/hotplug: Call into idle with a proper state</title>
<updated>2016-03-01T19:36:57+00:00</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2016-02-26T18:43:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=fc6d73d67436e7784758a831227bd019547a3f73'/>
<id>fc6d73d67436e7784758a831227bd019547a3f73</id>
<content type='text'>
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 &lt;tglx@linutronix.de&gt;
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Rafael Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Cc: "Srivatsa S. Bhat" &lt;srivatsa@mit.edu&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: Sebastian Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Rusty Russell &lt;rusty@rustcorp.com.au&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Paul McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Paul Turner &lt;pjt@google.com&gt;
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;tglx@linutronix.de&gt;
Cc: linux-arch@vger.kernel.org
Cc: Rik van Riel &lt;riel@redhat.com&gt;
Cc: Rafael Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Cc: "Srivatsa S. Bhat" &lt;srivatsa@mit.edu&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Arjan van de Ven &lt;arjan@linux.intel.com&gt;
Cc: Sebastian Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Rusty Russell &lt;rusty@rustcorp.com.au&gt;
Cc: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Paul McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Paul Turner &lt;pjt@google.com&gt;
Link: http://lkml.kernel.org/r/20160226182341.614102639@linutronix.de
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: KVM: Remove unused hyp_pc field</title>
<updated>2016-02-29T18:34:15+00:00</updated>
<author>
<name>Marc Zyngier</name>
<email>marc.zyngier@arm.com</email>
</author>
<published>2016-01-05T18:57:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=311b5b363cd28aa778de083178f147f32622e331'/>
<id>311b5b363cd28aa778de083178f147f32622e331</id>
<content type='text'>
This field was never populated, and the panic code already
does something similar. Delete the related code.

Acked-by: Christoffer Dall &lt;christoffer.dall@linaro.org&gt;
Signed-off-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This field was never populated, and the panic code already
does something similar. Delete the related code.

Acked-by: Christoffer Dall &lt;christoffer.dall@linaro.org&gt;
Signed-off-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: KVM: Cleanup asm-offsets.c</title>
<updated>2016-02-29T18:34:15+00:00</updated>
<author>
<name>Marc Zyngier</name>
<email>marc.zyngier@arm.com</email>
</author>
<published>2016-01-05T18:54:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ff3a01d1e029847abb2d0735843ac6f7ae1385ea'/>
<id>ff3a01d1e029847abb2d0735843ac6f7ae1385ea</id>
<content type='text'>
Since we don't have much assembler left, most of the KVM stuff
in asm-offsets.c is now superfluous. Let's get rid of it.

Acked-by: Christoffer Dall &lt;christoffer.dall@linaro.org&gt;
Signed-off-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since we don't have much assembler left, most of the KVM stuff
in asm-offsets.c is now superfluous. Let's get rid of it.

Acked-by: Christoffer Dall &lt;christoffer.dall@linaro.org&gt;
Signed-off-by: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
