Commit Graph

12012 Commits

Author SHA1 Message Date
Alexander Potapenko
cd11016e5f mm, kasan: stackdepot implementation. Enable stackdepot for SLAB
Implement the stack depot and provide CONFIG_STACKDEPOT.  Stack depot
will allow KASAN store allocation/deallocation stack traces for memory
chunks.  The stack traces are stored in a hash table and referenced by
handles which reside in the kasan_alloc_meta and kasan_free_meta
structures in the allocated memory chunks.

IRQ stack traces are cut below the IRQ entry point to avoid unnecessary
duplication.

Right now stackdepot support is only enabled in SLAB allocator.  Once
KASAN features in SLAB are on par with those in SLUB we can switch SLUB
to stackdepot as well, thus removing the dependency on SLUB stack
bookkeeping, which wastes a lot of memory.

This patch is based on the "mm: kasan: stack depots" patch originally
prepared by Dmitry Chernenkov.

Joonsoo has said that he plans to reuse the stackdepot code for the
mm/page_owner.c debugging facility.

[akpm@linux-foundation.org: s/depot_stack_handle/depot_stack_handle_t]
[aryabinin@virtuozzo.com: comment style fixes]
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Alexander Potapenko
be7635e728 arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
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 <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>.  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 <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Linus Torvalds
e46b4e2b46 Nothing major this round. Mostly small clean ups and fixes.
Some visible changes:
 
  A new flag was added to distinguish traces done in NMI context.
 
  Preempt tracer now shows functions where preemption is disabled but
  interrupts are still enabled.
 
 Other notes:
 
  Updates were done to function tracing to allow better performance
  with perf.
 
  Infrastructure code has been added to allow for a new histogram
  feature for recording live trace event histograms that can be
  configured by simple user commands. The feature itself was just
  finished, but needs a round in linux-next before being pulled.
  This only includes some infrastructure changes that will be needed.
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Merge tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "Nothing major this round.  Mostly small clean ups and fixes.

  Some visible changes:

   - A new flag was added to distinguish traces done in NMI context.

   - Preempt tracer now shows functions where preemption is disabled but
     interrupts are still enabled.

  Other notes:

   - Updates were done to function tracing to allow better performance
     with perf.

   - Infrastructure code has been added to allow for a new histogram
     feature for recording live trace event histograms that can be
     configured by simple user commands.  The feature itself was just
     finished, but needs a round in linux-next before being pulled.

     This only includes some infrastructure changes that will be needed"

* tag 'trace-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (22 commits)
  tracing: Record and show NMI state
  tracing: Fix trace_printk() to print when not using bprintk()
  tracing: Remove redundant reset per-CPU buff in irqsoff tracer
  x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
  tracing: Fix crash from reading trace_pipe with sendfile
  tracing: Have preempt(irqs)off trace preempt disabled functions
  tracing: Fix return while holding a lock in register_tracer()
  ftrace: Use kasprintf() in ftrace_profile_tracefs()
  ftrace: Update dynamic ftrace calls only if necessary
  ftrace: Make ftrace_hash_rec_enable return update bool
  tracing: Fix typoes in code comment and printk in trace_nop.c
  tracing, writeback: Replace cgroup path to cgroup ino
  tracing: Use flags instead of bool in trigger structure
  tracing: Add an unreg_all() callback to trigger commands
  tracing: Add needs_rec flag to event triggers
  tracing: Add a per-event-trigger 'paused' field
  tracing: Add get_syscall_name()
  tracing: Add event record param to trigger_ops.func()
  tracing: Make event trigger functions available
  tracing: Make ftrace_event_field checking functions available
  ...
2016-03-24 10:52:25 -07:00
Linus Torvalds
3fa2fe2ce0 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This tree contains various perf fixes on the kernel side, plus three
  hw/event-enablement late additions:

   - Intel Memory Bandwidth Monitoring events and handling
   - the AMD Accumulated Power Mechanism reporting facility
   - more IOMMU events

  ... and a final round of perf tooling updates/fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
  perf llvm: Use strerror_r instead of the thread unsafe strerror one
  perf llvm: Use realpath to canonicalize paths
  perf tools: Unexport some methods unused outside strbuf.c
  perf probe: No need to use formatting strbuf method
  perf help: Use asprintf instead of adhoc equivalents
  perf tools: Remove unused perf_pathdup, xstrdup functions
  perf tools: Do not include stringify.h from the kernel sources
  tools include: Copy linux/stringify.h from the kernel
  tools lib traceevent: Remove redundant CPU output
  perf tools: Remove needless 'extern' from function prototypes
  perf tools: Simplify die() mechanism
  perf tools: Remove unused DIE_IF macro
  perf script: Remove lots of unused arguments
  perf thread: Rename perf_event__preprocess_sample_addr to thread__resolve
  perf machine: Rename perf_event__preprocess_sample to machine__resolve
  perf tools: Add cpumode to struct perf_sample
  perf tests: Forward the perf_sample in the dwarf unwind test
  perf tools: Remove misplaced __maybe_unused
  perf list: Fix documentation of :ppp
  perf bench numa: Fix assertion for nodes bitfield
  ...
2016-03-24 10:02:14 -07:00
Linus Torvalds
d88f48e128 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - fix hotplug bugs
   - fix irq live lock
   - fix various topology handling bugs
   - fix APIC ACK ordering
   - fix PV iopl handling
   - fix speling
   - fix/tweak memcpy_mcsafe() return value
   - fix fbcon bug
   - remove stray prototypes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/msr: Remove unused native_read_tscp()
  x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck
  x86/oprofile/nmi: Add missing hotplug FROZEN handling
  x86/hpet: Use proper mask to modify hotplug action
  x86/apic/uv: Fix the hotplug notifier
  x86/apb/timer: Use proper mask to modify hotplug action
  x86/topology: Use total_cpus not nr_cpu_ids for logical packages
  x86/topology: Fix Intel HT disable
  x86/topology: Fix logical package mapping
  x86/irq: Cure live lock in fixup_irqs()
  x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known()
  x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt()
  x86/iopl: Fix iopl capability check on Xen PV
  x86/iopl/64: Properly context-switch IOPL on Xen PV
  selftests/x86: Add an iopl test
  x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe()
  x86/video: Don't assume all FB devices are PCI devices
  arch/x86/irq: Purge useless handler declarations from hw_irq.h
  x86: Fix misspellings in comments
2016-03-24 09:47:32 -07:00
Linus Torvalds
a24e3d414e Merge branch 'akpm' (patches from Andrew)
Merge third patch-bomb from Andrew Morton:

 - more ocfs2 changes

 - a few hotfixes

 - Andy's compat cleanups

 - misc fixes to fatfs, ptrace, coredump, cpumask, creds, eventfd,
   panic, ipmi, kgdb, profile, kfifo, ubsan, etc.

 - many rapidio updates: fixes, new drivers.

 - kcov: kernel code coverage feature.  Like gcov, but not
   "prohibitively expensive".

 - extable code consolidation for various archs

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (81 commits)
  ia64/extable: use generic search and sort routines
  x86/extable: use generic search and sort routines
  s390/extable: use generic search and sort routines
  alpha/extable: use generic search and sort routines
  kernel/...: convert pr_warning to pr_warn
  drivers: dma-coherent: use memset_io for DMA_MEMORY_IO mappings
  drivers: dma-coherent: use MEMREMAP_WC for DMA_MEMORY_MAP
  memremap: add MEMREMAP_WC flag
  memremap: don't modify flags
  kernel/signal.c: add compile-time check for __ARCH_SI_PREAMBLE_SIZE
  mm/mprotect.c: don't imply PROT_EXEC on non-exec fs
  ipc/sem: make semctl setting sempid consistent
  ubsan: fix tree-wide -Wmaybe-uninitialized false positives
  kfifo: fix sparse complaints
  scripts/gdb: account for changes in module data structure
  scripts/gdb: add cmdline reader command
  scripts/gdb: add version command
  kernel: add kcov code coverage
  profile: hide unused functions when !CONFIG_PROC_FS
  hpwdt: use nmi_panic() when kernel panics in NMI handler
  ...
2016-03-22 17:09:14 -07:00
Dmitry Vyukov
5c9a8750a6 kernel: add kcov code coverage
kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing).  Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system.  A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/).  However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.

kcov does not aim to collect as much coverage as possible.  It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g.  scheduler, locking).

Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes.  Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch).  I've
dropped the second mode for simplicity.

This patch adds the necessary support on kernel side.  The complimentary
compiler support was added in gcc revision 231296.

We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:

  https://github.com/google/syzkaller/wiki/Found-Bugs

We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation".  For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.

Why not gcov.  Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat.  A
typical coverage can be just a dozen of basic blocks (e.g.  an invalid
input).  In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M).  Cost of
kcov depends only on number of executed basic blocks/edges.  On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.

kcov exposes kernel PCs and control flow to user-space which is
insecure.  But debugfs should not be mapped as user accessible.

Based on a patch by Quentin Casasnovas.

[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: syzkaller <syzkaller@googlegroups.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Tavis Ormandy <taviso@google.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Kostya Serebryany <kcc@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@google.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: David Drysdale <drysdale@google.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Andy Lutomirski
f970165bee x86/compat: remove is_compat_task()
x86's is_compat_task always checked the current syscall type, not the
task type.  It has no non-arch users any more, so just remove it to
avoid confusion.

On x86, nothing should really be checking the task ABI.  There are
legitimate users for the syscall ABI and for the mm ABI.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-22 15:36:02 -07:00
Rik van Riel
9db284f303 kvm, rt: change async pagefault code locking for PREEMPT_RT
The async pagefault wake code can run from the idle task in exception
context, so everything here needs to be made non-preemptible.

Conversion to a simple wait queue and raw spinlock does the trick.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 16:38:38 +01:00
Huang Rui
01fe03ff1c x86/cpufeature, perf/x86: Add AMD Accumulated Power Mechanism feature flag
AMD CPU family 15h model 0x60 introduces a mechanism for measuring
accumulated power. It is used to report the processor power consumption
and support for it is indicated by CPUID Fn8000_0007_EDX[12].

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hector Marco-Gisbert <hecmargi@upv.es>
Cc: Jacob Shin <jacob.w.shin@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Kristen Carlson Accardi <kristen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Wan Zongshun <Vincent.Wan@amd.com>
Cc: spg_linux_kernel@amd.com
Link: http://lkml.kernel.org/r/1452739808-11871-4-git-send-email-ray.huang@amd.com
[ Resolved conflict and moved the synthetic CPUID slot to 19. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:35:29 +01:00
Huang Rui
8dfeae0d73 perf/x86/amd: Move nodes_per_socket into bsp_init_amd()
nodes_per_socket is static and it needn't be initialized many
times during every CPU core init. So move its initialization into
bsp_init_amd().

Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hector Marco-Gisbert <hecmargi@upv.es>
Cc: Jacob Shin <jacob.w.shin@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <rric@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: spg_linux_kernel@amd.com
Link: http://lkml.kernel.org/r/1452739808-11871-2-git-send-email-ray.huang@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:08:22 +01:00
Vikas Shivappa
33c3cc7acf perf/x86/mbm: Add Intel Memory B/W Monitoring enumeration and init
The MBM init patch enumerates the Intel MBM (Memory b/w monitoring)
and initializes the perf events and datastructures for monitoring the
memory b/w.

Its based on original patch series by Tony Luck and Kanaka Juvva.

Memory bandwidth monitoring (MBM) provides OS/VMM a way to monitor
bandwidth from one level of cache to another. The current patches
support L3 external bandwidth monitoring. It supports both 'local
bandwidth' and 'total bandwidth' monitoring for the socket. Local
bandwidth measures the amount of data sent through the memory controller
on the socket and total b/w measures the total system bandwidth.

Extending the cache quality of service monitoring (CQM) we add two
more events to the perf infrastructure:

  intel_cqm_llc/local_bytes - bytes sent through local socket memory controller
  intel_cqm_llc/total_bytes - total L3 external bytes sent

The tasks are associated with a Resouce Monitoring ID (RMID) just like
in CQM and OS uses a MSR write to indicate the RMID of the task during
scheduling.

Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: fenghua.yu@intel.com
Cc: h.peter.anvin@intel.com
Cc: ravi.v.shankar@intel.com
Cc: vikas.shivappa@intel.com
Link: http://lkml.kernel.org/r/1457652732-4499-4-git-send-email-vikas.shivappa@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 09:08:19 +01:00
Linus Torvalds
643ad15d47 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 protection key support from Ingo Molnar:
 "This tree adds support for a new memory protection hardware feature
  that is available in upcoming Intel CPUs: 'protection keys' (pkeys).

  There's a background article at LWN.net:

      https://lwn.net/Articles/643797/

  The gist is that protection keys allow the encoding of
  user-controllable permission masks in the pte.  So instead of having a
  fixed protection mask in the pte (which needs a system call to change
  and works on a per page basis), the user can map a (handful of)
  protection mask variants and can change the masks runtime relatively
  cheaply, without having to change every single page in the affected
  virtual memory range.

  This allows the dynamic switching of the protection bits of large
  amounts of virtual memory, via user-space instructions.  It also
  allows more precise control of MMU permission bits: for example the
  executable bit is separate from the read bit (see more about that
  below).

  This tree adds the MM infrastructure and low level x86 glue needed for
  that, plus it adds a high level API to make use of protection keys -
  if a user-space application calls:

        mmap(..., PROT_EXEC);

  or

        mprotect(ptr, sz, PROT_EXEC);

  (note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
  this special case, and will set a special protection key on this
  memory range.  It also sets the appropriate bits in the Protection
  Keys User Rights (PKRU) register so that the memory becomes unreadable
  and unwritable.

  So using protection keys the kernel is able to implement 'true'
  PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
  PROT_READ as well.  Unreadable executable mappings have security
  advantages: they cannot be read via information leaks to figure out
  ASLR details, nor can they be scanned for ROP gadgets - and they
  cannot be used by exploits for data purposes either.

  We know about no user-space code that relies on pure PROT_EXEC
  mappings today, but binary loaders could start making use of this new
  feature to map binaries and libraries in a more secure fashion.

  There is other pending pkeys work that offers more high level system
  call APIs to manage protection keys - but those are not part of this
  pull request.

  Right now there's a Kconfig that controls this feature
  (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
  (like most x86 CPU feature enablement code that has no runtime
  overhead), but it's not user-configurable at the moment.  If there's
  any serious problem with this then we can make it configurable and/or
  flip the default"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
  mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
  x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
  mm/core, x86/mm/pkeys: Add execute-only protection keys support
  x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
  x86/mm/pkeys: Allow kernel to modify user pkey rights register
  x86/fpu: Allow setting of XSAVE state
  x86/mm: Factor out LDT init from context init
  mm/core, x86/mm/pkeys: Add arch_validate_pkey()
  mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
  x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
  x86/mm/pkeys: Add Kconfig prompt to existing config option
  x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
  x86/mm/pkeys: Dump PKRU with other kernel registers
  mm/core, x86/mm/pkeys: Differentiate instruction fetches
  x86/mm/pkeys: Optimize fault handling in access_error()
  mm/core: Do not enforce PKEY permissions on remote mm access
  um, pkeys: Add UML arch_*_access_permitted() methods
  mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
  x86/mm/gup: Simplify get_user_pages() PTE bit handling
  ...
2016-03-20 19:08:56 -07:00
Linus Torvalds
24b5e20f11 Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes are:

   - Use separate EFI page tables when executing EFI firmware code.
     This isolates the EFI context from the rest of the kernel, which
     has security and general robustness advantages.  (Matt Fleming)

   - Run regular UEFI firmware with interrupts enabled.  This is already
     the status quo under other OSs.  (Ard Biesheuvel)

   - Various x86 EFI enhancements, such as the use of non-executable
     attributes for EFI memory mappings.  (Sai Praneeth Prakhya)

   - Various arm64 UEFI enhancements.  (Ard Biesheuvel)

   - ... various fixes and cleanups.

  The separate EFI page tables feature got delayed twice already,
  because it's an intrusive change and we didn't feel confident about
  it - third time's the charm we hope!"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  x86/mm/pat: Fix boot crash when 1GB pages are not supported by the CPU
  x86/efi: Only map kernel text for EFI mixed mode
  x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables
  x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
  efi/arm*: Perform hardware compatibility check
  efi/arm64: Check for h/w support before booting a >4 KB granular kernel
  efi/arm: Check for LPAE support before booting a LPAE kernel
  efi/arm-init: Use read-only early mappings
  efi/efistub: Prevent __init annotations from being used
  arm64/vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections
  efi/arm64: Drop __init annotation from handle_kernel_image()
  x86/mm/pat: Use _PAGE_GLOBAL bit for EFI page table mappings
  efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled
  efi: Reformat GUID tables to follow the format in UEFI spec
  efi: Add Persistent Memory type name
  efi: Add NV memory attribute
  x86/efi: Show actual ending addresses in efi_print_memmap
  x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0
  efivars: Use to_efivar_entry
  efi: Runtime-wrapper: Get rid of the rtc_lock spinlock
  ...
2016-03-20 18:58:18 -07:00
Linus Torvalds
26660a4046 Merge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull 'objtool' stack frame validation from Ingo Molnar:
 "This tree adds a new kernel build-time object file validation feature
  (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation.
  It was written by and is maintained by Josh Poimboeuf.

  The motivation: there's a category of hard to find kernel bugs, most
  of them in assembly code (but also occasionally in C code), that
  degrades the quality of kernel stack dumps/backtraces.  These bugs are
  hard to detect at the source code level.  Such bugs result in
  incorrect/incomplete backtraces most of time - but can also in some
  rare cases result in crashes or other undefined behavior.

  The build time correctness checking is done via the new 'objtool'
  user-space utility that was written for this purpose and which is
  hosted in the kernel repository in tools/objtool/.  The tool's (very
  simple) UI and source code design is shaped after Git and perf and
  shares quite a bit of infrastructure with tools/perf (which tooling
  infrastructure sharing effort got merged via perf and is already
  upstream).  Objtool follows the well-known kernel coding style.

  Objtool does not try to check .c or .S files, it instead analyzes the
  resulting .o generated machine code from first principles: it decodes
  the instruction stream and interprets it.  (Right now objtool supports
  the x86-64 architecture.)

  From tools/objtool/Documentation/stack-validation.txt:

   "The kernel CONFIG_STACK_VALIDATION option enables a host tool named
    objtool which runs at compile time.  It has a "check" subcommand
    which analyzes every .o file and ensures the validity of its stack
    metadata.  It enforces a set of rules on asm code and C inline
    assembly code so that stack traces can be reliable.

    Currently it only checks frame pointer usage, but there are plans to
    add CFI validation for C files and CFI generation for asm files.

    For each function, it recursively follows all possible code paths
    and validates the correct frame pointer state at each instruction.

    It also follows code paths involving special sections, like
    .altinstructions, __jump_table, and __ex_table, which can add
    alternative execution paths to a given instruction (or set of
    instructions).  Similarly, it knows how to follow switch statements,
    for which gcc sometimes uses jump tables."

  When this new kernel option is enabled (it's disabled by default), the
  tool, if it finds any suspicious assembly code pattern, outputs
  warnings in compiler warning format:

    warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch
    warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup
    warning: objtool:__schedule()+0x3c0: duplicate frame pointer save
    warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer

  ... so that scripts that pick up compiler warnings will notice them.
  All known warnings triggered by the tool are fixed by the tree, most
  of the commits in fact prepare the kernel to be warning-free.  Most of
  them are bugfixes or cleanups that stand on their own, but there are
  also some annotations of 'special' stack frames for justified cases
  such entries to JIT-ed code (BPF) or really special boot time code.

  There are two other long-term motivations behind this tool as well:

   - To improve the quality and reliability of kernel stack frames, so
     that they can be used for optimized live patching.

   - To create independent infrastructure to check the correctness of
     CFI stack frames at build time.  CFI debuginfo is notoriously
     unreliable and we cannot use it in the kernel as-is without extra
     checking done both on the kernel side and on the build side.

  The quality of kernel stack frames matters to debuggability as well,
  so IMO we can merge this without having to consider the live patching
  or CFI debuginfo angle"

* 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  objtool: Only print one warning per function
  objtool: Add several performance improvements
  tools: Copy hashtable.h into tools directory
  objtool: Fix false positive warnings for functions with multiple switch statements
  objtool: Rename some variables and functions
  objtool: Remove superflous INIT_LIST_HEAD
  objtool: Add helper macros for traversing instructions
  objtool: Fix false positive warnings related to sibling calls
  objtool: Compile with debugging symbols
  objtool: Detect infinite recursion
  objtool: Prevent infinite recursion in noreturn detection
  objtool: Detect and warn if libelf is missing and don't break the build
  tools: Support relative directory path for 'O='
  objtool: Support CROSS_COMPILE
  x86/asm/decoder: Use explicitly signed chars
  objtool: Enable stack metadata validation on 64-bit x86
  objtool: Add CONFIG_STACK_VALIDATION option
  objtool: Add tool to perform compile-time stack metadata validation
  x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard
  sched: Always inline context_switch()
  ...
2016-03-20 18:23:21 -07:00
Ard Biesheuvel
142b9e6c9d x86/kallsyms: fix GOLD link failure with new relative kallsyms table format
Commit 2213e9a66b ("kallsyms: add support for relative offsets in
kallsyms address table") changed the default kallsyms symbol table
format to use relative references rather than absolute addresses.

This reduces the size of the kallsyms symbol table by 50% on 64-bit
architectures, and further reduces the size of the relocation tables
used by relocatable kernels.  Since the memory footprint of the static
kernel image is always much smaller than 4 GB, these relative references
are assumed to be representable in 32 bits, even when the native word
size is 64 bits.

On 64-bit architectures, this obviously only works if the distance
between each relative reference and the chosen anchor point is
representable in 32 bits, and so the table generation code in
scripts/kallsyms.c scans the table for the lowest value that is covered
by the kernel text, and selects it as the anchor point.

However, when using the GOLD linker rather than the default BFD linker
to build the x86_64 kernel, the symbol phys_offset_64, which is the
result of arithmetic defined in the linker script, is emitted as a 'T'
rather than an 'A' type symbol, resulting in scripts/kallsyms.c to
mistake it for a suitable anchor point, even though it is far away from
the actual kernel image in the virtual address space.  This results in
out-of-range warnings from scripts/kallsyms.c and a broken build.

So let's align with the BFD linker, and emit the phys_offset_[32|64]
symbols as absolute symbols explicitly.  Note that the out of range
issue does not exist on 32-bit x86, but this patch changes both symbols
for symmetry.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-20 13:52:37 -07:00
Linus Torvalds
1200b6809d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...
2016-03-19 10:05:34 -07:00
Thomas Gleixner
f80be5e3d5 x86/hpet: Use proper mask to modify hotplug action
Magic hex constants are a guarantee for wreckage when the defines change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-19 13:40:08 +01:00
Thomas Gleixner
f47ab81aca x86/apic/uv: Fix the hotplug notifier
The notifier is missing the CPU_DOWN_FAILED transition. That leaves the
heartbeat disabled when CPU_DOWN_PREPARE fails.

It also does not handle the FROZEN transition variants. That might not be an
issue for UV, but it's inconsistent.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dimitri Sivanich <sivanich@sgi.com>
2016-03-19 13:40:08 +01:00
Thomas Gleixner
a38f98735e x86/apb/timer: Use proper mask to modify hotplug action
Magic hex constants are a guarantee for wreckage when the defines change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-19 13:40:08 +01:00
Thomas Gleixner
3e8db2246b x86/topology: Use total_cpus not nr_cpu_ids for logical packages
nr_cpu_ids can be limited on the command line via nr_cpus=. That can break the
logical package management because it results in a smaller number of packages,
but the cpus to online are occupying the full package space as the hyper
threads are enumerated after the physical cores typically.

total_cpus is the real possible cpu space not limited by nr_cpus command line
and gives us the proper number of packages.

Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Fixes: 1f12e32f4c ("x86/topology: Create logical package id")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Xiong Zhou <jencce.kernel@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andreas Herrmann <aherrmann@suse.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1603181254330.3978@nanos
2016-03-19 10:26:40 +01:00
Peter Zijlstra
63d1e995be x86/topology: Fix Intel HT disable
As per the comment in the code; due to BIOS it is sometimes impossible to know
if there actually are smp siblings until the machine is fully enumerated. So
we rather overestimate the number of possible packages.

Fixes: 1f12e32f4c ("x86/topology: Create logical package id")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: aherrmann@suse.com
Cc: jencce.kernel@gmail.com
Cc: bp@alien8.de
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Link: http://lkml.kernel.org/r/20160318150538.611014173@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-19 10:26:40 +01:00
Peter Zijlstra
b5d5f27d93 x86/topology: Fix logical package mapping
That first branch testing pkg against __max_logical_packages is wrong,
because if the first pkg id is larger, then the find_first_zero will
find us logical package id 0. However, if the second pkg id is indeed
0, we'll again claim it without testing if it was already taken.

Also, it fails to print the mapping.

Fixes: 1f12e32f4c ("x86/topology: Create logical package id")
Reported-by: Xiong Zhou <jencce.kernel@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: aherrmann@suse.com
Cc: bp@alien8.de
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Link: http://lkml.kernel.org/r/20160317095220.GO6344@twins.programming.kicks-ass.net
Link: http://lkml.kernel.org/r/20160318150538.482393396@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-19 10:26:40 +01:00
Li Bin
9d2099ab05 x86: ftrace: Fix the misleading comment for arch/x86/kernel/ftrace.c
Fix the misleading comment for arch/x86/kernel/ftrace.c that it
had used nop instead of jmp.

Signed-off-by: Li Bin <huawei.libin@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-03-18 15:54:01 -04:00
Thomas Gleixner
551adc6057 x86/irq: Cure live lock in fixup_irqs()
Harry reported, that he's able to trigger a system freeze with cpu hot
unplug. The freeze turned out to be a live lock caused by recent changes in
irq_force_complete_move().

When fixup_irqs() and from there irq_force_complete_move() is called on the
dying cpu, then all other cpus are in stop machine an wait for the dying cpu
to complete the teardown. If there is a move of an interrupt pending then
irq_force_complete_move() sends the cleanup IPI to the cpus in the old_domain
mask and waits for them to clear the mask. That's obviously impossible as
those cpus are firmly stuck in stop machine with interrupts disabled.

I should have known that, but I completely overlooked it being concentrated on
the locking issues around the vectors. And the existance of the call to
__irq_complete_move() in the code, which actually sends the cleanup IPI made
it reasonable to wait for that cleanup to complete. That call was bogus even
before the recent changes as it was just a pointless distraction.

We have to look at two cases:

1) The move_in_progress flag of the interrupt is set

   This means the ioapic has been updated with the new vector, but it has not
   fired yet. In theory there is a race:

   set_ioapic(new_vector) <-- Interrupt is raised before update is effective,
   			      i.e. it's raised on the old vector. 

   So if the target cpu cannot handle that interrupt before the old vector is
   cleaned up, we get a spurious interrupt and in the worst case the ioapic
   irq line becomes stale, but my experiments so far have only resulted in
   spurious interrupts.

   But in case of cpu hotplug this should be a non issue because if the
   affinity update happens right before all cpus rendevouz in stop machine,
   there is no way that the interrupt can be blocked on the target cpu because
   all cpus loops first with interrupts enabled in stop machine, so the old
   vector is not yet cleaned up when the interrupt fires.

   So the only way to run into this issue is if the delivery of the interrupt
   on the apic/system bus would be delayed beyond the point where the target
   cpu disables interrupts in stop machine. I doubt that it can happen, but at
   least there is a theroretical chance. Virtualization might be able to
   expose this, but AFAICT the IOAPIC emulation is not as stupid as the real
   hardware.

   I've spent quite some time over the weekend to enforce that situation,
   though I was not able to trigger the delayed case.

2) The move_in_progress flag is not set and the old_domain cpu mask is not
   empty.

   That means, that an interrupt was delivered after the change and the
   cleanup IPI has been sent to the cpus in old_domain, but not all CPUs have
   responded to it yet.

In both cases we can assume that the next interrupt will arrive on the new
vector, so we can cleanup the old vectors on the cpus in the old_domain cpu
mask.

Fixes: 98229aa36c "x86/irq: Plug vector cleanup race"
Reported-by: Harry Junior <harryjr@outlook.fr>
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Joe Lawrence <joe.lawrence@stratus.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1603140931430.3657@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-18 14:51:06 +01:00
Thomas Gleixner
f508a5ba7a x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known()
The topology_core_cpumask is used to find a neighbour cpu in
calibrate_delay_is_known(). It might not be allocated at the first invocation
of that function on the boot cpu, when CONFIG_CPUMASK_OFFSTACK is set.

The mask is allocated later in native_smp_prepare_cpus. As a consequence the
underlying find_next_bit() call dereferences a NULL pointer.

Add a proper check to prevent this.

Fixes: c25323c073 "x86/tsc: Use topology functions"
Reported-and-tested-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1603180843270.3978@nanos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-03-18 14:51:06 +01:00
Kees Cook
4cc7ecb7f2 param: convert some "on"/"off" users to strtobool
This changes several users of manual "on"/"off" parsing to use
strtobool.

Some side-effects:
- these uses will now parse y/n/1/0 meaningfully too
- the early_param uses will now bubble up parse errors

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Joe Perches <joe@perches.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steve French <sfrench@samba.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Kirill A. Shutemov
3ed3a4f0dd mm: cleanup *pte_alloc* interfaces
There are few things about *pte_alloc*() helpers worth cleaning up:

 - 'vma' argument is unused, let's drop it;

 - most __pte_alloc() callers do speculative check for pmd_none(),
   before taking ptl: let's introduce pte_alloc() macro which does
   the check.

   The only direct user of __pte_alloc left is userfaultfd, which has
   different expectation about atomicity wrt pmd.

 - pte_alloc_map() and pte_alloc_map_lock() are redefined using
   pte_alloc().

[sudeep.holla@arm.com: fix build for arm64 hugetlbpage]
[sfr@canb.auug.org.au: fix arch/arm/mm/mmu.c some more]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Andy Lutomirski
c29016cf41 x86/iopl: Fix iopl capability check on Xen PV
iopl(3) is supposed to work if iopl is already 3, even if
unprivileged.  This didn't work right on Xen PV.  Fix it.

Reviewewd-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/8ce12013e6e4c0a44a97e316be4a6faff31bd5ea.1458162709.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-17 09:49:27 +01:00
Andy Lutomirski
b7a584598a x86/iopl/64: Properly context-switch IOPL on Xen PV
On Xen PV, regs->flags doesn't reliably reflect IOPL and the
exit-to-userspace code doesn't change IOPL.  We need to context
switch it manually.

I'm doing this without going through paravirt because this is
specific to Xen PV.  After the dust settles, we can merge this with
the 32-bit code, tidy up the iopl syscall implementation, and remove
the set_iopl pvop entirely.

Fixes XSA-171.

Reviewewd-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/693c3bd7aeb4d3c27c92c622b7d0f554a458173c.1458162709.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-17 09:49:26 +01:00
Ingo Molnar
00f5268501 Merge branch 'x86/cleanups' into x86/urgent
Pull in some merge window leftovers.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-17 09:44:57 +01:00
Linus Torvalds
271ecc5253 Merge branch 'akpm' (patches from Andrew)
Merge first patch-bomb from Andrew Morton:

 - some misc things

 - ofs2 updates

 - about half of MM

 - checkpatch updates

 - autofs4 update

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits)
  autofs4: fix string.h include in auto_dev-ioctl.h
  autofs4: use pr_xxx() macros directly for logging
  autofs4: change log print macros to not insert newline
  autofs4: make autofs log prints consistent
  autofs4: fix some white space errors
  autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked()
  autofs4: fix coding style line length in autofs4_wait()
  autofs4: fix coding style problem in autofs4_get_set_timeout()
  autofs4: coding style fixes
  autofs: show pipe inode in mount options
  kallsyms: add support for relative offsets in kallsyms address table
  kallsyms: don't overload absolute symbol type for percpu symbols
  x86: kallsyms: disable absolute percpu symbols on !SMP
  checkpatch: fix another left brace warning
  checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses
  checkpatch: warn on bare unsigned or signed declarations without int
  checkpatch: exclude asm volatile from complex macro check
  mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate()
  mm: migrate: consolidate mem_cgroup_migrate() calls
  mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
  ...
2016-03-16 11:51:08 -07:00
Christian Borntraeger
288cf3c64e x86: query dynamic DEBUG_PAGEALLOC setting
We can use debug_pagealloc_enabled() to check if we can map the identity
mapping with 2MB pages.  We can also add the state into the dump_stack
output.

The patch does not touch the code for the 1GB pages, which ignored
CONFIG_DEBUG_PAGEALLOC.  Do we need to fence this as well?

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
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
Linus Torvalds
df2e37c814 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The 4.6 pile of irq updates contains:

   - Support for IPI irqdomains to support proper integration of IPIs to
     and from coprocessors.  The first user of this new facility is
     MIPS.  The relevant MIPS patches come with the core to avoid merge
     ordering issues and have been acked by Ralf.

   - A new command line option to set the default interrupt affinity
     mask at boot time.

   - Support for some more new ARM and MIPS interrupt controllers:
     tango, alpine-msix and bcm6345-l1

   - Two small cleanups for x86/apic which we merged into irq/core to
     avoid yet another branch in x86 with two tiny commits.

   - The usual set of updates, cleanups in drivers/irqchip.  Mostly in
     the area of ARM-GIC, arada-37-xp and atmel chips.  Nothing
     outstanding here"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  irqchip/irq-alpine-msi: Release the correct domain on error
  irqchip/mxs: Fix error check of of_io_request_and_map()
  irqchip/sunxi-nmi: Fix error check of of_io_request_and_map()
  genirq: Export IRQ functions for module use
  irqchip/gic/realview: Support more RealView DCC variants
  Documentation/bindings: Document the Alpine MSIX driver
  irqchip: Add the Alpine MSIX interrupt controller
  irqchip/gic-v3: Always return IRQ_SET_MASK_OK_DONE in gic_set_affinity
  irqchip/gic-v3-its: Mark its_init() and its children as __init
  irqchip/gic-v3: Remove gic_root_node variable from the ITS code
  irqchip/gic-v3: ACPI: Add redistributor support via GICC structures
  irqchip/gic-v3: Add ACPI support for GICv3/4 initialization
  irqchip/gic-v3: Refactor gic_of_init() for GICv3 driver
  x86/apic: Deinline _flat_send_IPI_mask, save ~150 bytes
  x86/apic: Deinline __default_send_IPI_*, save ~200 bytes
  dt-bindings: interrupt-controller: Add SoC-specific compatible string to Marvell ODMI
  irqchip/mips-gic: Add new DT property to reserve IPIs
  MIPS: Delete smp-gic.c
  MIPS: Make smp CMP, CPS and MT use the new generic IPI functions
  MIPS: Add generic SMP IPI support
  ...
2016-03-15 12:48:48 -07:00
Linus Torvalds
8a284c062e Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The timer department delivers this time:

   - Support for cross clock domain timestamps in the core code plus a
     first user.  That allows more precise timestamping for PTP and
     later for audio and other peripherals.

     The ptp/e1000e patches have been acked by the relevant maintainers
     and are carried in the timer tree to avoid merge ordering issues.

   - Support for unregistering the current clocksource watchdog.  That
     lifts a limitation for switching clocksources which has been there
     from day 1

   - The usual pile of fixes and updates to the core and the drivers.
     Nothing outstanding and exciting"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  time/timekeeping: Work around false positive GCC warning
  e1000e: Adds hardware supported cross timestamp on e1000e nic
  ptp: Add PTP_SYS_OFFSET_PRECISE for driver crosstimestamping
  x86/tsc: Always Running Timer (ART) correlated clocksource
  hrtimer: Revert CLOCK_MONOTONIC_RAW support
  time: Add history to cross timestamp interface supporting slower devices
  time: Add driver cross timestamp interface for higher precision time synchronization
  time: Remove duplicated code in ktime_get_raw_and_real()
  time: Add timekeeping snapshot code capturing system time and counter
  time: Add cycles to nanoseconds translation
  jiffies: Use CLOCKSOURCE_MASK instead of constant
  clocksource: Introduce clocksource_freq2mult()
  clockevents/drivers/exynos_mct: Implement ->set_state_oneshot_stopped()
  clockevents/drivers/arm_global_timer: Implement ->set_state_oneshot_stopped()
  clockevents/drivers/arm_arch_timer: Implement ->set_state_oneshot_stopped()
  clocksource/drivers/arm_global_timer: Register delay timer
  clocksource/drivers/lpc32xx: Support timer-based ARM delay
  clocksource/drivers/lpc32xx: Support periodic mode
  clocksource/drivers/lpc32xx: Don't use the prescaler counter for clockevents
  clocksource/drivers/rockchip: Add err handle for rk_timer_init
  ...
2016-03-15 12:13:56 -07:00
Linus Torvalds
ae465beeff Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 timer update from Ingo Molnar:
 "A single simplification of the x86 TSC code"

* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/tsc: Use topology functions
2016-03-15 11:29:24 -07:00
Linus Torvalds
13c76ad872 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Enable full ASLR randomization for 32-bit programs (Hector
     Marco-Gisbert)

   - Add initial minimal INVPCI support, to flush global mappings (Andy
     Lutomirski)

   - Add KASAN enhancements (Andrey Ryabinin)

   - Fix mmiotrace for huge pages (Karol Herbst)

   - ... misc cleanups and small enhancements"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/32: Enable full randomization on i386 and X86_32
  x86/mm/kmmio: Fix mmiotrace for hugepages
  x86/mm: Avoid premature success when changing page attributes
  x86/mm/ptdump: Remove paravirt_enabled()
  x86/mm: Fix INVPCID asm constraint
  x86/dmi: Switch dmi_remap() from ioremap() [uncached] to ioremap_cache()
  x86/mm: If INVPCID is available, use it to flush global mappings
  x86/mm: Add a 'noinvpcid' boot option to turn off INVPCID
  x86/mm: Add INVPCID helpers
  x86/kasan: Write protect kasan zero shadow
  x86/kasan: Clear kasan_zero_page after TLB flush
  x86/mm/numa: Check for failures in numa_clear_kernel_node_hotplug()
  x86/mm/numa: Clean up numa_clear_kernel_node_hotplug()
  x86/mm: Make kmap_prot into a #define
  x86/mm/32: Set NX in __supported_pte_mask before enabling paging
  x86/mm: Streamline and restore probe_memory_block_size()
2016-03-15 10:45:39 -07:00
Linus Torvalds
9cf8d6360c Merge branch 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode updates from Ingo Molnar:
 "The biggest change in this cycle was the separation of the microcode
  loading mechanism from the initrd code plus the support of built-in
  microcode images.

  There were also lots cleanups and general restructuring (by Borislav
  Petkov)"

* 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/microcode/intel: Drop orig_sum from ext signature checksum
  x86/microcode/intel: Improve microcode sanity-checking error messages
  x86/microcode/intel: Merge two consecutive if-statements
  x86/microcode/intel: Get rid of DWSIZE
  x86/microcode/intel: Change checksum variables to u32
  x86/microcode: Use kmemdup() rather than duplicating its implementation
  x86/microcode: Remove unnecessary paravirt_enabled check
  x86/microcode: Document builtin microcode loading method
  x86/microcode/AMD: Issue microcode updated message later
  x86/microcode/intel: Cleanup get_matching_model_microcode()
  x86/microcode/intel: Remove unused arg of get_matching_model_microcode()
  x86/microcode/intel: Rename mc_saved_in_initrd
  x86/microcode/intel: Use *wrmsrl variants
  x86/microcode/intel: Cleanup apply_microcode_intel()
  x86/microcode/intel: Move the BUG_ON up and turn it into WARN_ON
  x86/microcode/intel: Rename mc_intel variable to mc
  x86/microcode/intel: Rename mc_saved_count to num_saved
  x86/microcode/intel: Rename local variables of type struct mc_saved_data
  x86/microcode/AMD: Drop redundant printk prefix
  x86/microcode: Issue update message only once
  ...
2016-03-15 10:39:22 -07:00
Linus Torvalds
ecc026bff6 Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fpu updates from Ingo Molnar:
 "The biggest change in terms of impact is the changing of the FPU
  context switch model to 'eagerfpu' for all CPU types, via: commit
  58122bf1d8: "x86/fpu: Default eagerfpu=on on all CPUs"

  This makes all FPU saves and restores synchronous and makes the FPU
  code a lot more obvious to read.  In the next cycle, if this change is
  problem free, we'll remove the old lazy FPU restore code altogether.

  This change flushed out some old bugs, which should all be fixed by
  now, BYMMV"

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Default eagerfpu=on on all CPUs
  x86/fpu: Speed up lazy FPU restores slightly
  x86/fpu: Fold fpu_copy() into fpu__copy()
  x86/fpu: Fix FNSAVE usage in eagerfpu mode
  x86/fpu: Fix math emulation in eager fpu mode
2016-03-15 10:23:56 -07:00
Linus Torvalds
42576bee6e Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Early command line options parsing enhancements from Dave Hansen, plus
  minor cleanups and enhancements"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Remove unused 'is_big_kernel' variable
  x86/boot: Use proper array element type in memset() size calculation
  x86/boot: Pass in size to early cmdline parsing
  x86/boot: Simplify early command line parsing
  x86/boot: Fix early command-line parsing when partial word matches
  x86/boot: Fix early command-line parsing when matching at end
  x86/boot: Simplify kernel load address alignment check
  x86/boot: Micro-optimize reset_early_page_tables()
2016-03-15 10:02:25 -07:00
Linus Torvalds
ba33ea811e Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "This is another big update. Main changes are:

   - lots of x86 system call (and other traps/exceptions) entry code
     enhancements.  In particular the complex parts of the 64-bit entry
     code have been migrated to C code as well, and a number of dusty
     corners have been refreshed.  (Andy Lutomirski)

   - vDSO special mapping robustification and general cleanups (Andy
     Lutomirski)

   - cpufeature refactoring, cleanups and speedups (Borislav Petkov)

   - lots of other changes ..."

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits)
  x86/cpufeature: Enable new AVX-512 features
  x86/entry/traps: Show unhandled signal for i386 in do_trap()
  x86/entry: Call enter_from_user_mode() with IRQs off
  x86/entry/32: Change INT80 to be an interrupt gate
  x86/entry: Improve system call entry comments
  x86/entry: Remove TIF_SINGLESTEP entry work
  x86/entry/32: Add and check a stack canary for the SYSENTER stack
  x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup
  x86/entry: Only allocate space for tss_struct::SYSENTER_stack if needed
  x86/entry: Vastly simplify SYSENTER TF (single-step) handling
  x86/entry/traps: Clear DR6 early in do_debug() and improve the comment
  x86/entry/traps: Clear TIF_BLOCKSTEP on all debug exceptions
  x86/entry/32: Restore FLAGS on SYSEXIT
  x86/entry/32: Filter NT and speed up AC filtering in SYSENTER
  x86/entry/compat: In SYSENTER, sink AC clearing below the existing FLAGS test
  selftests/x86: In syscall_nt, test NT|TF as well
  x86/asm-offsets: Remove PARAVIRT_enabled
  x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled
  uprobes: __create_xol_area() must nullify xol_mapping.fault
  x86/cpufeature: Create a new synthetic cpu capability for machine check recovery
  ...
2016-03-15 09:32:27 -07:00
Linus Torvalds
d88bfe1d68 Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RAS updates from Ingo Molnar:
 "Various RAS updates:

   - AMD MCE support updates for future CPUs, fixes and 'SMCA' (Scalable
     MCA) error decoding support (Aravind Gopalakrishnan)

   - x86 memcpy_mcsafe() support, to enable smart(er) hardware error
     recovery in NVDIMM drivers, based on an extension of the x86
     exception handling code.  (Tony Luck)"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  EDAC/sb_edac: Fix computation of channel address
  x86/mm, x86/mce: Add memcpy_mcsafe()
  x86/mce/AMD: Document some functionality
  x86/mce: Clarify comments regarding deferred error
  x86/mce/AMD: Fix logic to obtain block address
  x86/mce/AMD, EDAC: Enable error decoding of Scalable MCA errors
  x86/mce: Move MCx_CONFIG MSR definitions
  x86/mce: Check for faults tagged in EXTABLE_CLASS_FAULT exception table entries
  x86/mm: Expand the exception table logic to allow new handling options
  x86/mce/AMD: Set MCAX Enable bit
  x86/mce/AMD: Carve out threshold block preparation
  x86/mce/AMD: Fix LVT offset configuration for thresholding
  x86/mce/AMD: Reduce number of blocks scanned per bank
  x86/mce/AMD: Do not perform shared bank check for future processors
  x86/mce: Fix order of AMD MCE init function call
2016-03-14 18:43:51 -07:00
Linus Torvalds
e71c2c1eeb Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "Main kernel side changes:

   - Big reorganization of the x86 perf support code.  The old code grew
     organically deep inside arch/x86/kernel/cpu/perf* and its naming
     became somewhat messy.

     The new location is under arch/x86/events/, using the following
     cleaner hierarchy of source code files:

       perf/x86: Move perf_event.c .................. => x86/events/core.c
       perf/x86: Move perf_event_amd.c .............. => x86/events/amd/core.c
       perf/x86: Move perf_event_amd_ibs.c .......... => x86/events/amd/ibs.c
       perf/x86: Move perf_event_amd_iommu.[ch] ..... => x86/events/amd/iommu.[ch]
       perf/x86: Move perf_event_amd_uncore.c ....... => x86/events/amd/uncore.c
       perf/x86: Move perf_event_intel_bts.c ........ => x86/events/intel/bts.c
       perf/x86: Move perf_event_intel.c ............ => x86/events/intel/core.c
       perf/x86: Move perf_event_intel_cqm.c ........ => x86/events/intel/cqm.c
       perf/x86: Move perf_event_intel_cstate.c ..... => x86/events/intel/cstate.c
       perf/x86: Move perf_event_intel_ds.c ......... => x86/events/intel/ds.c
       perf/x86: Move perf_event_intel_lbr.c ........ => x86/events/intel/lbr.c
       perf/x86: Move perf_event_intel_pt.[ch] ...... => x86/events/intel/pt.[ch]
       perf/x86: Move perf_event_intel_rapl.c ....... => x86/events/intel/rapl.c
       perf/x86: Move perf_event_intel_uncore.[ch] .. => x86/events/intel/uncore.[ch]
       perf/x86: Move perf_event_intel_uncore_nhmex.c => x86/events/intel/uncore_nmhex.c
       perf/x86: Move perf_event_intel_uncore_snb.c   => x86/events/intel/uncore_snb.c
       perf/x86: Move perf_event_intel_uncore_snbep.c => x86/events/intel/uncore_snbep.c
       perf/x86: Move perf_event_knc.c .............. => x86/events/intel/knc.c
       perf/x86: Move perf_event_p4.c ............... => x86/events/intel/p4.c
       perf/x86: Move perf_event_p6.c ............... => x86/events/intel/p6.c
       perf/x86: Move perf_event_msr.c .............. => x86/events/msr.c

     (Borislav Petkov)

   - Update various x86 PMU constraint and hw support details (Stephane
     Eranian)

   - Optimize kprobes for BPF execution (Martin KaFai Lau)

   - Rewrite, refactor and fix the Intel uncore PMU driver code (Thomas
     Gleixner)

   - Rewrite, refactor and fix the Intel RAPL PMU code (Thomas Gleixner)

   - Various fixes and smaller cleanups.

  There are lots of perf tooling updates as well.  A few highlights:

  perf report/top:

     - Hierarchy histogram mode for 'perf top' and 'perf report',
       showing multiple levels, one per --sort entry: (Namhyung Kim)

       On a mostly idle system:

         # perf top --hierarchy -s comm,dso

       Then expand some levels and use 'P' to take a snapshot:

         # cat perf.hist.0
         -  92.32%         perf
               58.20%         perf
               22.29%         libc-2.22.so
                5.97%         [kernel]
                4.18%         libelf-0.165.so
                1.69%         [unknown]
         -   4.71%         qemu-system-x86
                3.10%         [kernel]
                1.60%         qemu-system-x86_64 (deleted)
         +   2.97%         swapper
         #

     - Add 'L' hotkey to dynamicly set the percent threshold for
       histogram entries and callchains, i.e.  dynamicly do what the
       --percent-limit command line option to 'top' and 'report' does.
       (Namhyung Kim)

  perf mem:

     - Allow specifying events via -e in 'perf mem record', also listing
       what events can be specified via 'perf mem record -e list' (Jiri
       Olsa)

  perf record:

     - Add 'perf record' --all-user/--all-kernel options, so that one
       can tell that all the events in the command line should be
       restricted to the user or kernel levels (Jiri Olsa), i.e.:

         perf record -e cycles:u,instructions:u

       is equivalent to:

         perf record --all-user -e cycles,instructions

     - Make 'perf record' collect CPU cache info in the perf.data file header:

         $ perf record usleep 1
         [ perf record: Woken up 1 times to write data ]
         [ perf record: Captured and wrote 0.017 MB perf.data (7 samples) ]
         $ perf report --header-only -I | tail -10 | head -8
         # CPU cache info:
         #  L1 Data                 32K [0-1]
         #  L1 Instruction          32K [0-1]
         #  L1 Data                 32K [2-3]
         #  L1 Instruction          32K [2-3]
         #  L2 Unified             256K [0-1]
         #  L2 Unified             256K [2-3]
         #  L3 Unified            4096K [0-3]

       Will be used in 'perf c2c' and eventually in 'perf diff' to
       allow, for instance running the same workload in multiple
       machines and then when using 'diff' show the hardware difference.
       (Jiri Olsa)

     - Improved support for Java, using the JVMTI agent library to do
       jitdumps that then will be inserted in synthesized
       PERF_RECORD_MMAP2 events via 'perf inject' pointed to synthesized
       ELF files stored in ~/.debug and keyed with build-ids, to allow
       symbol resolution and even annotation with source line info, see
       the changeset comments to see how to use it (Stephane Eranian)

  perf script/trace:

     - Decode data_src values (e.g.  perf.data files generated by 'perf
       mem record') in 'perf script': (Jiri Olsa)

         # perf script
           perf 693 [1] 4.088652: 1 cpu/mem-loads,ldlat=30/P: ffff88007d0b0f40 68100142 L1 hit|SNP None|TLB L1 or L2 hit|LCK No <SNIP>
                                                                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     - Improve support to 'data_src', 'weight' and 'addr' fields in
       'perf script' (Jiri Olsa)

     - Handle empty print fmts in 'perf script -s' i.e. when running
       python or perl scripts (Taeung Song)

  perf stat:

     - 'perf stat' now shows shadow metrics (insn per cycle, etc) in
       interval mode too.  E.g:

         # perf stat -I 1000 -e instructions,cycles sleep 1
         #         time   counts unit events
            1.000215928  519,620      instructions     #  0.69 insn per cycle
            1.000215928  752,003      cycles
         <SNIP>

     - Port 'perf kvm stat' to PowerPC (Hemant Kumar)

     - Implement CSV metrics output in 'perf stat' (Andi Kleen)

  perf BPF support:

     - Support converting data from bpf events in 'perf data' (Wang Nan)

     - Print bpf-output events in 'perf script': (Wang Nan).

         # perf record -e bpf-output/no-inherit,name=evt/ -e ./test_bpf_output_3.c/map:channel.event=evt/ usleep 1000
         # perf script
            usleep  4882 21384.532523:   evt:  ffffffff810e97d1 sys_nanosleep ([kernel.kallsyms])
             BPF output: 0000: 52 61 69 73 65 20 61 20  Raise a
                         0008: 42 50 46 20 65 76 65 6e  BPF even
                         0010: 74 21 00 00              t!..
             BPF string: "Raise a BPF event!"
         #

     - Add API to set values of map entries in a BPF object, be it
       individual map slots or ranges (Wang Nan)

     - Introduce support for the 'bpf-output' event (Wang Nan)

     - Add glue to read perf events in a BPF program (Wang Nan)

     - Improve support for bpf-output events in 'perf trace' (Wang Nan)

  ... and tons of other changes as well - see the shortlog and git log
  for details!"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (342 commits)
  perf stat: Add --metric-only support for -A
  perf stat: Implement --metric-only mode
  perf stat: Document CSV format in manpage
  perf hists browser: Check sort keys before hot key actions
  perf hists browser: Allow thread filtering for comm sort key
  perf tools: Add sort__has_comm variable
  perf tools: Recalc total periods using top-level entries in hierarchy
  perf tools: Remove nr_sort_keys field
  perf hists browser: Cleanup hist_browser__fprintf_hierarchy_entry()
  perf tools: Remove hist_entry->fmt field
  perf tools: Fix command line filters in hierarchy mode
  perf tools: Add more sort entry check functions
  perf tools: Fix hist_entry__filter() for hierarchy
  perf jitdump: Build only on supported archs
  tools lib traceevent: Add '~' operation within arg_num_eval()
  perf tools: Omit unnecessary cast in perf_pmu__parse_scale
  perf tools: Pass perf_hpp_list all the way through setup_sort_list
  perf tools: Fix perf script python database export crash
  perf jitdump: DWARF is also needed
  perf bench mem: Prepare the x86-64 build for upstream memcpy_mcsafe() changes
  ...
2016-03-14 17:58:53 -07:00
Linus Torvalds
d09e356ad0 Merge branch 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull read-only kernel memory updates from Ingo Molnar:
 "This tree adds two (security related) enhancements to the kernel's
  handling of read-only kernel memory:

   - extend read-only kernel memory to a new class of formerly writable
     kernel data: 'post-init read-only memory' via the __ro_after_init
     attribute, and mark the ARM and x86 vDSO as such read-only memory.

     This kind of attribute can be used for data that requires a once
     per bootup initialization sequence, but is otherwise never modified
     after that point.

     This feature was based on the work by PaX Team and Brad Spengler.

     (by Kees Cook, the ARM vDSO bits by David Brown.)

   - make CONFIG_DEBUG_RODATA always enabled on x86 and remove the
     Kconfig option.  This simplifies the kernel and also signals that
     read-only memory is the default model and a first-class citizen.
     (Kees Cook)"

* 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM/vdso: Mark the vDSO code read-only after init
  x86/vdso: Mark the vDSO code read-only after init
  lkdtm: Verify that '__ro_after_init' works correctly
  arch: Introduce post-init read-only memory
  x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option
  mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
  asm-generic: Consolidate mark_rodata_ro()
2016-03-14 16:58:50 -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
Fenghua Yu
d050049442 x86/cpufeature: Enable new AVX-512 features
A few new AVX-512 instruction groups/features are added in cpufeatures.h
for enuermation: AVX512DQ, AVX512BW, and AVX512VL.

Clear the flags in fpu__xstate_clear_all_cpu_caps().

The specification for latest AVX-512 including the features can be found at:

  https://software.intel.com/sites/default/files/managed/07/b7/319433-023.pdf

Note, I didn't enable the flags in KVM. Hopefully the KVM guys can pick up
the flags and enable them in KVM.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Ravi V Shankar <ravi.v.shankar@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/1457667498-37357-1-git-send-email-fenghua.yu@intel.com
[ Added more detailed feature descriptions. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-12 17:30:53 +01:00
Borislav Petkov
6e6867093d x86/fpu: Fix eager-FPU handling on legacy FPU machines
i486 derived cores like Intel Quark support only the very old,
legacy x87 FPU (FSAVE/FRSTOR, CPUID bit FXSR is not set), and
our FPU code wasn't handling the saving and restoring there
properly in the 'eagerfpu' case.

So after we made eagerfpu the default for all CPU types:

  58122bf1d8 x86/fpu: Default eagerfpu=on on all CPUs

these old FPU designs broke. First, Andy Shevchenko reported a splat:

  WARNING: CPU: 0 PID: 823 at arch/x86/include/asm/fpu/internal.h:163 fpu__clear+0x8c/0x160

which was us trying to execute FXRSTOR on those machines even though
they don't support it.

After taking care of that, Bryan O'Donoghue reported that a simple FPU
test still failed because we weren't initializing the FPU state properly
on those machines.

Take care of all that.

Reported-and-tested-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Reported-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20160311113206.GD4312@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-12 16:13:55 +01:00
Jianyu Zhan
10ee73865e x86/entry/traps: Show unhandled signal for i386 in do_trap()
Commit abd4f7505b ("x86: i386-show-unhandled-signals-v3") did turn on
the showing-unhandled-signal behaviour for i386 for some exception handlers,
but for no reason do_trap() is left out (my naive guess is because turning it on
for do_trap() would be too noisy since do_trap() is shared by several exceptions).

And since the same commit make "show_unhandled_signals" a debug tunable(in
/proc/sys/debug/exception-trace), and x86 by default turning it on.

So it would be strange for i386 users who turing it on manually and expect
seeing the unhandled signal output in log, but nothing.

This patch turns it on for i386 in do_trap() as well.

Signed-off-by: Jianyu Zhan <nasa4836@gmail.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bp@suse.de
Cc: dave.hansen@linux.intel.com
Cc: heukelum@fastmail.fm
Cc: jbeulich@novell.com
Cc: jdike@addtoit.com
Cc: joe@perches.com
Cc: luto@kernel.org
Link: http://lkml.kernel.org/r/1457612398-4568-1-git-send-email-nasa4836@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-10 18:37:25 +01:00