Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
Pull x86 EFI update from Peter Anvin:
"EFI tree, from Matt Fleming. Most of the patches are the new efivarfs
filesystem by Matt Garrett & co. The balance are support for EFI
wallclock in the absence of a hardware-specific driver, and various
fixes and cleanups."
* 'core-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
efivarfs: Make efivarfs_fill_super() static
x86, efi: Check table header length in efi_bgrt_init()
efivarfs: Use query_variable_info() to limit kmalloc()
efivarfs: Fix return value of efivarfs_file_write()
efivarfs: Return a consistent error when efivarfs_get_inode() fails
efivarfs: Make 'datasize' unsigned long
efivarfs: Add unique magic number
efivarfs: Replace magic number with sizeof(attributes)
efivarfs: Return an error if we fail to read a variable
efi: Clarify GUID length calculations
efivarfs: Implement exclusive access for {get,set}_variable
efivarfs: efivarfs_fill_super() ensure we clean up correctly on error
efivarfs: efivarfs_fill_super() ensure we free our temporary name
efivarfs: efivarfs_fill_super() fix inode reference counts
efivarfs: efivarfs_create() ensure we drop our reference on inode on error
efivarfs: efivarfs_file_read ensure we free data in error paths
x86-64/efi: Use EFI to deal with platform wall clock (again)
x86/kernel: remove tboot 1:1 page table creation code
x86, efi: 1:1 pagetable mapping for virtual EFI calls
x86, mm: Include the entire kernel memory map in trampoline_pgd
...
Pull x86 RAS update from Ingo Molnar:
"Rework all config variables used throughout the MCA code and collect
them together into a mca_config struct. This keeps them tightly and
neatly packed together instead of spilled all over the place.
Then, convert those which are used as booleans into real booleans and
save some space. These bits are exposed via
/sys/devices/system/machinecheck/machinecheck*/"
* 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, MCA: Finish mca_config conversion
x86, MCA: Convert the next three variables batch
x86, MCA: Convert rip_msr, mce_bootlog, monarch_timeout
x86, MCA: Convert dont_log_ce, banks and tolerant
drivers/base: Add a DEVICE_BOOL_ATTR macro
Pull KVM updates from Marcelo Tosatti:
"Considerable KVM/PPC work, x86 kvmclock vsyscall support,
IA32_TSC_ADJUST MSR emulation, amongst others."
Fix up trivial conflict in kernel/sched/core.c due to cross-cpu
migration notifier added next to rq migration call-back.
* tag 'kvm-3.8-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (156 commits)
KVM: emulator: fix real mode segment checks in address linearization
VMX: remove unneeded enable_unrestricted_guest check
KVM: VMX: fix DPL during entry to protected mode
x86/kexec: crash_vmclear_local_vmcss needs __rcu
kvm: Fix irqfd resampler list walk
KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump
x86/kexec: VMCLEAR VMCSs loaded on all cpus if necessary
KVM: MMU: optimize for set_spte
KVM: PPC: booke: Get/set guest EPCR register using ONE_REG interface
KVM: PPC: bookehv: Add EPCR support in mtspr/mfspr emulation
KVM: PPC: bookehv: Add guest computation mode for irq delivery
KVM: PPC: Make EPCR a valid field for booke64 and bookehv
KVM: PPC: booke: Extend MAS2 EPN mask for 64-bit
KVM: PPC: e500: Mask MAS2 EPN high 32-bits in 32/64 tlbwe emulation
KVM: PPC: Mask ea's high 32-bits in 32/64 instr emulation
KVM: PPC: e500: Add emulation helper for getting instruction ea
KVM: PPC: bookehv64: Add support for interrupt handling
KVM: PPC: bookehv: Remove GET_VCPU macro from exception handler
KVM: PPC: booke: Fix get_tb() compile error on 64-bit
KVM: PPC: e500: Silence bogus GCC warning in tlb code
...
- Add necessary infrastructure to make balloon driver work under ARM.
- Add /dev/xen/privcmd interfaces to work with ARM and PVH.
- Improve Xen PCIBack wild-card parsing.
- Add Xen ACPI PAD (Processor Aggregator) support - so can offline/online
sockets depending on the power consumption.
- PVHVM + kexec = use an E820_RESV region for the shared region so we don't
overwrite said region during kexec reboot.
- Cleanups, compile fixes.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
iQEcBAABAgAGBQJQyJaAAAoJEFjIrFwIi8fJ9DoIALAjj3qaGDimykc/RPSu2MLL
Tfchb1su0WxSu6fP17jBadq39Qna85UzZATMCyN47k8wB3KoSEW13rqwe7JSsdT/
SEfZDrlbhNK+JAWJETx+6gq7J7dMwi/tFt4CbwPv/zAHb7C7JyzEgKctbi4Q1e89
FFMXZru2IWDbaqlcJQjJcE/InhWy5vKW3bY5nR/Bz0RBf9lk/WHbcJwLXirsDcKk
uMVmPy4yiApX6ZCPbYP5BZvsIFkmLKQEfpmwdzbLGDoL7N1onqq/lgYNgZqPJUkE
XL1GVBbRGpy+NQr++vUS1NiRyR81EChRO3IrDZwzvNEPqKa9GoF5U1CdRh71R5I=
=uZQZ
-----END PGP SIGNATURE-----
Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen updates from Konrad Rzeszutek Wilk:
- Add necessary infrastructure to make balloon driver work under ARM.
- Add /dev/xen/privcmd interfaces to work with ARM and PVH.
- Improve Xen PCIBack wild-card parsing.
- Add Xen ACPI PAD (Processor Aggregator) support - so can offline/
online sockets depending on the power consumption.
- PVHVM + kexec = use an E820_RESV region for the shared region so we
don't overwrite said region during kexec reboot.
- Cleanups, compile fixes.
Fix up some trivial conflicts due to the balloon driver now working on
ARM, and there were changes next to the previous work-arounds that are
now gone.
* tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/PVonHVM: fix compile warning in init_hvm_pv_info
xen: arm: implement remap interfaces needed for privcmd mappings.
xen: correctly use xen_pfn_t in remap_domain_mfn_range.
xen: arm: enable balloon driver
xen: balloon: allow PVMMU interfaces to be compiled out
xen: privcmd: support autotranslated physmap guests.
xen: add pages parameter to xen_remap_domain_mfn_range
xen/acpi: Move the xen_running_on_version_or_later function.
xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h
xen/acpi: Fix compile error by missing decleration for xen_domain.
xen/acpi: revert pad config check in xen_check_mwait
xen/acpi: ACPI PAD driver
xen-pciback: reject out of range inputs
xen-pciback: simplify and tighten parsing of device IDs
xen PVonHVM: use E820_Reserved area for shared_info
Host bridge hotplug:
- Untangle _PRT from struct pci_bus (Bjorn Helgaas)
- Request _OSC control before scanning root bus (Taku Izumi)
- Assign resources when adding host bridge (Yinghai Lu)
- Remove root bus when removing host bridge (Yinghai Lu)
- Remove _PRT during hot remove (Yinghai Lu)
SRIOV
- Add sysfs knobs to control numVFs (Don Dutile)
Power management
- Notify devices when power resource turned on (Huang Ying)
Bug fixes
- Work around broken _SEG on HP xw9300 (Bjorn Helgaas)
- Keep runtime PM enabled for unbound PCI devices (Huang Ying)
- Fix Optimus dual-GPU runtime D3 suspend issue (Dave Airlie)
- Fix xen frontend shutdown issue (David Vrabel)
- Work around PLX PCI 9050 BAR alignment erratum (Ian Abbott)
Miscellaneous
- Add GPL license for drivers/pci/ioapic (Andrew Cooks)
- Add standard PCI-X, PCIe ASPM register #defines (Bjorn Helgaas)
- NumaChip remote PCI support (Daniel Blueman)
- Fix PCIe Link Capabilities Supported Link Speed definition (Jingoo Han)
- Convert dev_printk() to dev_info(), etc (Joe Perches)
- Add support for non PCI BAR ROM data (Matthew Garrett)
- Add x86 support for host bridge translation offset (Mike Yoknis)
- Report success only when every driver supports AER (Vijay Pandarathil)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.10 (GNU/Linux)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=OE3Q
-----END PGP SIGNATURE-----
Merge tag 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI update from Bjorn Helgaas:
"Host bridge hotplug:
- Untangle _PRT from struct pci_bus (Bjorn Helgaas)
- Request _OSC control before scanning root bus (Taku Izumi)
- Assign resources when adding host bridge (Yinghai Lu)
- Remove root bus when removing host bridge (Yinghai Lu)
- Remove _PRT during hot remove (Yinghai Lu)
SRIOV
- Add sysfs knobs to control numVFs (Don Dutile)
Power management
- Notify devices when power resource turned on (Huang Ying)
Bug fixes
- Work around broken _SEG on HP xw9300 (Bjorn Helgaas)
- Keep runtime PM enabled for unbound PCI devices (Huang Ying)
- Fix Optimus dual-GPU runtime D3 suspend issue (Dave Airlie)
- Fix xen frontend shutdown issue (David Vrabel)
- Work around PLX PCI 9050 BAR alignment erratum (Ian Abbott)
Miscellaneous
- Add GPL license for drivers/pci/ioapic (Andrew Cooks)
- Add standard PCI-X, PCIe ASPM register #defines (Bjorn Helgaas)
- NumaChip remote PCI support (Daniel Blueman)
- Fix PCIe Link Capabilities Supported Link Speed definition (Jingoo
Han)
- Convert dev_printk() to dev_info(), etc (Joe Perches)
- Add support for non PCI BAR ROM data (Matthew Garrett)
- Add x86 support for host bridge translation offset (Mike Yoknis)
- Report success only when every driver supports AER (Vijay
Pandarathil)"
Fix up trivial conflicts.
* tag 'for-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (48 commits)
PCI: Use phys_addr_t for physical ROM address
x86/PCI: Add NumaChip remote PCI support
ath9k: Use standard #defines for PCIe Capability ASPM fields
iwlwifi: Use standard #defines for PCIe Capability ASPM fields
iwlwifi: collapse wrapper for pcie_capability_read_word()
iwlegacy: Use standard #defines for PCIe Capability ASPM fields
iwlegacy: collapse wrapper for pcie_capability_read_word()
cxgb3: Use standard #defines for PCIe Capability ASPM fields
PCI: Add standard PCIe Capability Link ASPM field names
PCI/portdrv: Use PCI Express Capability accessors
PCI: Use standard PCIe Capability Link register field names
x86: Use PCI setup data
PCI: Add support for non-BAR ROMs
PCI: Add pcibios_add_device
EFI: Stash ROMs if they're not in the PCI BAR
PCI: Add and use standard PCI-X Capability register names
PCI/PM: Keep runtime PM enabled for unbound PCI devices
xen-pcifront: Handle backend CLOSED without CLOSING
PCI: SRIOV control and status via sysfs (documentation)
PCI/AER: Report success only when every device has AER-aware driver
...
Pull big execve/kernel_thread/fork unification series from Al Viro:
"All architectures are converted to new model. Quite a bit of that
stuff is actually shared with architecture trees; in such cases it's
literally shared branch pulled by both, not a cherry-pick.
A lot of ugliness and black magic is gone (-3KLoC total in this one):
- kernel_thread()/kernel_execve()/sys_execve() redesign.
We don't do syscalls from kernel anymore for either kernel_thread()
or kernel_execve():
kernel_thread() is essentially clone(2) with callback run before we
return to userland, the callbacks either never return or do
successful do_execve() before returning.
kernel_execve() is a wrapper for do_execve() - it doesn't need to
do transition to user mode anymore.
As a result kernel_thread() and kernel_execve() are
arch-independent now - they live in kernel/fork.c and fs/exec.c
resp. sys_execve() is also in fs/exec.c and it's completely
architecture-independent.
- daemonize() is gone, along with its parts in fs/*.c
- struct pt_regs * is no longer passed to do_fork/copy_process/
copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump.
- sys_fork()/sys_vfork()/sys_clone() unified; some architectures
still need wrappers (ones with callee-saved registers not saved in
pt_regs on syscall entry), but the main part of those suckers is in
kernel/fork.c now."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits)
do_coredump(): get rid of pt_regs argument
print_fatal_signal(): get rid of pt_regs argument
ptrace_signal(): get rid of unused arguments
get rid of ptrace_signal_deliver() arguments
new helper: signal_pt_regs()
unify default ptrace_signal_deliver
flagday: kill pt_regs argument of do_fork()
death to idle_regs()
don't pass regs to copy_process()
flagday: don't pass regs to copy_thread()
bfin: switch to generic vfork, get rid of pointless wrappers
xtensa: switch to generic clone()
openrisc: switch to use of generic fork and clone
unicore32: switch to generic clone(2)
score: switch to generic fork/vfork/clone
c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone()
take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h
mn10300: switch to generic fork/vfork/clone
h8300: switch to generic fork/vfork/clone
tile: switch to generic clone()
...
Conflicts:
arch/microblaze/include/asm/Kbuild
Pull x86 timer update from Ingo Molnar:
"This tree includes HPET fixes and also implements a calibration-free,
TSC match driven APIC timer interrupt mode: 'TSC deadline mode'
supported in SandyBridge and later CPUs."
* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: hpet: Fix inverted return value check in arch_setup_hpet_msi()
x86: hpet: Fix masking of MSI interrupts
x86: apic: Use tsc deadline for oneshot when available
Pull "Nuke 386-DX/SX support" from Ingo Molnar:
"This tree removes ancient-386-CPUs support and thus zaps quite a bit
of complexity:
24 files changed, 56 insertions(+), 425 deletions(-)
... which complexity has plagued us with extra work whenever we wanted
to change SMP primitives, for years.
Unfortunately there's a nostalgic cost: your old original 386 DX33
system from early 1991 won't be able to boot modern Linux kernels
anymore. Sniff."
I'm not sentimental. Good riddance.
* 'x86-nuke386-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, 386 removal: Document Nx586 as a 386 and thus unsupported
x86, cleanups: Simplify sync_core() in the case of no CPUID
x86, 386 removal: Remove CONFIG_X86_POPAD_OK
x86, 386 removal: Remove CONFIG_X86_WP_WORKS_OK
x86, 386 removal: Remove CONFIG_INVLPG
x86, 386 removal: Remove CONFIG_BSWAP
x86, 386 removal: Remove CONFIG_XADD
x86, 386 removal: Remove CONFIG_CMPXCHG
x86, 386 removal: Remove CONFIG_M386 from Kconfig
Pull x86 topology discovery improvements from Ingo Molnar:
"These changes improve topology discovery on AMD CPUs.
Right now this feeds information displayed in
/sys/devices/system/cpu/cpuX/cache/indexY/* - but in the future we
could use this to set up a better scheduling topology."
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, cacheinfo: Base cache sharing info on CPUID 0x8000001d on AMD
x86, cacheinfo: Make use of CPUID 0x8000001d for cache information on AMD
x86, cacheinfo: Determine number of cache leafs using CPUID 0x8000001d on AMD
x86: Add cpu_has_topoext
Pull x86 BSP hotplug changes from Ingo Molnar:
"This tree enables CPU#0 (the boot processor) to be onlined/offlined on
x86, just like any other CPU. Enabled on Intel CPUs for now.
Allowing this required the identification and fixing of latent CPU#0
assumptions (such as CPU#0 initializations, etc.) in the x86
architecture code, plus the identification of barriers to
BSP-offlining, such as active PIC interrupts which can only be
serviced on the BSP.
It's behind a default-off option, and there's a debug option that
allows the automatic testing of this feature.
The motivation of this feature is to allow and prepare for true
CPU-hotplug hardware support: recent changes to MCE support enable us
to detect a deteriorating but not yet hard-failing L1/L2 cache on a
CPU that could be soft-unplugged - or a failing L3 cache on a
multi-socket system.
Note that true hardware hot-plug is not yet fully enabled by this,
because that requires a special platform wakeup sequence to be sent to
the freshly powered up CPU#0. Future patches for this are planned,
once such a platform exists. Chicken and egg"
* 'x86-bsp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, topology: Debug CPU0 hotplug
x86/i387.c: Initialize thread xstate only on CPU0 only once
x86, hotplug: Handle retrigger irq by the first available CPU
x86, hotplug: The first online processor saves the MTRR state
x86, hotplug: During CPU0 online, enable x2apic, set_numa_node.
x86, hotplug: Wake up CPU0 via NMI instead of INIT, SIPI, SIPI
x86-32, hotplug: Add start_cpu0() entry point to head_32.S
x86-64, hotplug: Add start_cpu0() entry point to head_64.S
kernel/cpu.c: Add comment for priority in cpu_hotplug_pm_callback
x86, hotplug, suspend: Online CPU0 for suspend or hibernate
x86, hotplug: Support functions for CPU0 online/offline
x86, topology: Don't offline CPU0 if any PIC irq can not be migrated out of it
x86, Kconfig: Add config switch for CPU0 hotplug
doc: Add x86 CPU0 online/offline feature
Pull x86 asm changes from Ingo Molnar:
"Two fixlets and a cleanup."
* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86_32: Return actual stack when requesting sp from regs
x86: Don't clobber top of pt_regs in nested NMI
x86/asm: Clean up copy_page_*() comments and code
Pull perf updates from Ingo Molnar:
"Lots of activity:
211 files changed, 8328 insertions(+), 4116 deletions(-)
most of it on the tooling side.
Main changes:
* ftrace enhancements and fixes from Steve Rostedt.
* uprobes fixes, cleanups and preparation for the ARM port from Oleg
Nesterov.
* UAPI fixes, from David Howels - prepares the arch/x86 UAPI
transition
* Separate perf tests into multiple objects, one per test, from Jiri
Olsa.
* Make hardware event translations available in sysfs, from Jiri
Olsa.
* Fixes to /proc/pid/maps parsing, preparatory to supporting data
maps, from Namhyung Kim
* Implement ui_progress for GTK, from Namhyung Kim
* Add framework for automated perf_event_attr tests, where tools with
different command line options will be run from a 'perf test', via
python glue, and the perf syscall will be intercepted to verify
that the perf_event_attr fields set by the tool are those expected,
from Jiri Olsa
* Add a 'link' method for hists, so that we can have the leader with
buckets for all the entries in all the hists. This new method is
now used in the default 'diff' output, making the sum of the
'baseline' column be 100%, eliminating blind spots.
* libtraceevent fixes for compiler warnings trying to make perf it
build on some distros, like fedora 14, 32-bit, some of the warnings
really pointed to real bugs.
* Add a browser for 'perf script' and make it available from the
report and annotate browsers. It does filtering to find the
scripts that handle events found in the perf.data file used. From
Feng Tang
* perf inject changes to allow showing where a task sleeps, from
Andrew Vagin.
* Makefile improvements from Namhyung Kim.
* Add --pre and --post command hooks in 'stat', from Peter Zijlstra.
* Don't stop synthesizing threads when one vanishes, this is for the
existing threads when we start a tool like trace.
* Use sched:sched_stat_runtime to provide a thread summary, this
produces the same output as the 'trace summary' subcommand of
tglx's original "trace" tool.
* Support interrupted syscalls in 'trace'
* Add an event duration column and filter in 'trace'.
* There are references to the man pages in some tools, so try to
build Documentation when installing, warning the user if that is
not possible, from Borislav Petkov.
* Give user better message if precise is not supported, from David
Ahern.
* Try to find cross-built objdump path by using the session
environment information in the perf.data file header, from Irina
Tirdea, original patch and idea by Namhyung Kim.
* Diplays more output on features check for make V=1, so that one can
figure out what is happening by looking at gcc output, etc. From
Jiri Olsa.
* Add on_exit implementation for systems without one, e.g. Android,
from Bernhard Rosenkraenzer.
* Only process events for vcpus of interest, helps handling large
number of events, from David Ahern.
* Cross compilation fixes for Android, from Irina Tirdea.
* Add documentation on compiling for Android, from Irina Tirdea.
* perf diff improvements from Jiri Olsa.
* Target (task/user/cpu/syswide) handling improvements, from Namhyung
Kim.
* Add support in 'trace' for tracing workload given by command line,
from Namhyung Kim.
* ... and much more."
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (194 commits)
uprobes: Use percpu_rw_semaphore to fix register/unregister vs dup_mmap() race
perf evsel: Introduce is_group_member method
perf powerpc: Use uapi/unistd.h to fix build error
tools: Pass the target in descend
tools: Honour the O= flag when tool build called from a higher Makefile
tools: Define a Makefile function to do subdir processing
perf ui: Always compile browser setup code
perf ui: Add ui_progress__finish()
perf ui gtk: Implement ui_progress functions
perf ui: Introduce generic ui_progress helper
perf ui tui: Move progress.c under ui/tui directory
perf tools: Add basic event modifier sanity check
perf tools: Omit group members from perf_evlist__disable/enable
perf tools: Ensure single disable call per event in record comand
perf tools: Fix 'disabled' attribute config for record command
perf tools: Fix attributes for '{}' defined event groups
perf tools: Use sscanf for parsing /proc/pid/maps
perf tools: Add gtk.<command> config option for launching GTK browser
perf tools: Fix compile error on NO_NEWT=1 build
perf hists: Initialize all of he->stat with zeroes
...
Pull RCU update from Ingo Molnar:
"The major features of this tree are:
1. A first version of no-callbacks CPUs. This version prohibits
offlining CPU 0, but only when enabled via CONFIG_RCU_NOCB_CPU=y.
Relaxing this constraint is in progress, but not yet ready
for prime time. These commits were posted to LKML at
https://lkml.org/lkml/2012/10/30/724.
2. Changes to SRCU that allows statically initialized srcu_struct
structures. These commits were posted to LKML at
https://lkml.org/lkml/2012/10/30/296.
3. Restructuring of RCU's debugfs output. These commits were posted
to LKML at https://lkml.org/lkml/2012/10/30/341.
4. Additional CPU-hotplug/RCU improvements, posted to LKML at
https://lkml.org/lkml/2012/10/30/327.
Note that the commit eliminating __stop_machine() was judged to
be too-high of risk, so is deferred to 3.9.
5. Changes to RCU's idle interface, most notably a new module
parameter that redirects normal grace-period operations to
their expedited equivalents. These were posted to LKML at
https://lkml.org/lkml/2012/10/30/739.
6. Additional diagnostics for RCU's CPU stall warning facility,
posted to LKML at https://lkml.org/lkml/2012/10/30/315.
The most notable change reduces the
default RCU CPU stall-warning time from 60 seconds to 21 seconds,
so that it once again happens sooner than the softlockup timeout.
7. Documentation updates, which were posted to LKML at
https://lkml.org/lkml/2012/10/30/280.
A couple of late-breaking changes were posted at
https://lkml.org/lkml/2012/11/16/634 and
https://lkml.org/lkml/2012/11/16/547.
8. Miscellaneous fixes, which were posted to LKML at
https://lkml.org/lkml/2012/10/30/309.
9. Finally, a fix for an lockdep-RCU splat was posted to LKML
at https://lkml.org/lkml/2012/11/7/486."
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (49 commits)
context_tracking: New context tracking susbsystem
sched: Mark RCU reader in sched_show_task()
rcu: Separate accounting of callbacks from callback-free CPUs
rcu: Add callback-free CPUs
rcu: Add documentation for the new rcuexp debugfs trace file
rcu: Update documentation for TREE_RCU debugfs tracing
rcu: Reduce default RCU CPU stall warning timeout
rcu: Fix TINY_RCU rcu_is_cpu_rrupt_from_idle check
rcu: Clarify memory-ordering properties of grace-period primitives
rcu: Add new rcutorture module parameters to start/end test messages
rcu: Remove list_for_each_continue_rcu()
rcu: Fix batch-limit size problem
rcu: Add tracing for synchronize_sched_expedited()
rcu: Remove old debugfs interfaces and also RCU flavor name
rcu: split 'rcuhier' to each flavor
rcu: split 'rcugp' to each flavor
rcu: split 'rcuboost' to each flavor
rcu: split 'rcubarrier' to each flavor
rcu: Fix tracing formatting
rcu: Remove the interface "rcudata.csv"
...
Merge misc updates from Andrew Morton:
"About half of most of MM. Going very early this time due to
uncertainty over the coreautounifiednumasched things. I'll send the
other half of most of MM tomorrow. The rest of MM awaits a slab merge
from Pekka."
* emailed patches from Andrew Morton: (71 commits)
memory_hotplug: ensure every online node has NORMAL memory
memory_hotplug: handle empty zone when online_movable/online_kernel
mm, memory-hotplug: dynamic configure movable memory and portion memory
drivers/base/node.c: cleanup node_state_attr[]
bootmem: fix wrong call parameter for free_bootmem()
avr32, kconfig: remove HAVE_ARCH_BOOTMEM
mm: cma: remove watermark hacks
mm: cma: skip watermarks check for already isolated blocks in split_free_page()
mm, oom: fix race when specifying a thread as the oom origin
mm, oom: change type of oom_score_adj to short
mm: cleanup register_node()
mm, mempolicy: remove duplicate code
mm/vmscan.c: try_to_freeze() returns boolean
mm: introduce putback_movable_pages()
virtio_balloon: introduce migration primitives to balloon pages
mm: introduce compaction and migration for ballooned pages
mm: introduce a common interface for balloon pages mobility
mm: redefine address_space.assoc_mapping
mm: adjust address_space_operations.migratepage() return code
arch/sparc/kernel/sys_sparc_64.c: s/COLOUR/COLOR/
...
Update the x86_64 arch_get_unmapped_area[_topdown] functions to make use
of vm_unmapped_area() instead of implementing a brute force search.
Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
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>
There was some desire in large applications using MAP_HUGETLB or
SHM_HUGETLB to use 1GB huge pages on some mappings, and stay with 2MB on
others. This is useful together with NUMA policy: use 2MB interleaving
on some mappings, but 1GB on local mappings.
This patch extends the IPC/SHM syscall interfaces slightly to allow
specifying the page size.
It borrows some upper bits in the existing flag arguments and allows
encoding the log of the desired page size in addition to the *_HUGETLB
flag. When 0 is specified the default size is used, this makes the
change fully compatible.
Extending the internal hugetlb code to handle this is straight forward.
Instead of a single mount it just keeps an array of them and selects the
right mount based on the specified page size. When no page size is
specified it uses the mount of the default page size.
The change is not visible in /proc/mounts because internal mounts don't
appear there. It also has very little overhead: the additional mounts
just consume a super block, but not more memory when not used.
I also exported the new flags to the user headers (they were previously
under __KERNEL__). Right now only symbols for x86 and some other
architecture for 1GB and 2MB are defined. The interface should already
work for all other architectures though. Only architectures that define
multiple hugetlb sizes actually need it (that is currently x86, tile,
powerpc). However tile and powerpc have user configurable hugetlb
sizes, so it's not easy to add defines. A program on those
architectures would need to query sysfs and use the appropiate log2.
[akpm@linux-foundation.org: cleanups]
[rientjes@google.com: fix build]
[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Introduction of device PM QoS flags.
* ACPI device power management update allowing subsystems other than
PCI to use it more easily.
* ACPI device enumeration rework allowing additional kinds of devices
to be enumerated via ACPI. From Mika Westerberg, Adrian Hunter,
Mathias Nyman, Andy Shevchenko, and Rafael J. Wysocki.
* ACPICA update to version 20121018 from Bob Moore and Lv Zheng.
* ACPI memory hotplug update from Wen Congyang and Yasuaki Ishimatsu.
* Introduction of acpi_handle_<level>() messaging macros and ACPI-based CPU
hot-remove support from Toshi Kani.
* ACPI EC updates from Feng Tang.
* cpufreq updates from Viresh Kumar, Fabio Baltieri and others.
* cpuidle changes to quickly notice governor prediction failure from
Youquan Song.
* Support for using multiple cpuidle drivers at the same time and cpuidle
cleanups from Daniel Lezcano.
* devfreq updates from Nishanth Menon and others.
* cpupower update from Thomas Renninger.
* Fixes and small cleanups all over the place.
--
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.19 (GNU/Linux)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=6OEP
-----END PGP SIGNATURE-----
Merge tag 'pm+acpi-for-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI and power management updates from Rafael Wysocki:
- Introduction of device PM QoS flags.
- ACPI device power management update allowing subsystems other than
PCI to use it more easily.
- ACPI device enumeration rework allowing additional kinds of devices
to be enumerated via ACPI. From Mika Westerberg, Adrian Hunter,
Mathias Nyman, Andy Shevchenko, and Rafael J. Wysocki.
- ACPICA update to version 20121018 from Bob Moore and Lv Zheng.
- ACPI memory hotplug update from Wen Congyang and Yasuaki Ishimatsu.
- Introduction of acpi_handle_<level>() messaging macros and ACPI-based
CPU hot-remove support from Toshi Kani.
- ACPI EC updates from Feng Tang.
- cpufreq updates from Viresh Kumar, Fabio Baltieri and others.
- cpuidle changes to quickly notice governor prediction failure from
Youquan Song.
- Support for using multiple cpuidle drivers at the same time and
cpuidle cleanups from Daniel Lezcano.
- devfreq updates from Nishanth Menon and others.
- cpupower update from Thomas Renninger.
- Fixes and small cleanups all over the place.
* tag 'pm+acpi-for-3.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (196 commits)
mmc: sdhci-acpi: enable runtime-pm for device HID INT33C6
ACPI: add Haswell LPSS devices to acpi_platform_device_ids list
ACPI: add documentation about ACPI 5 enumeration
pnpacpi: fix incorrect TEST_ALPHA() test
ACPI / PM: Fix header of acpi_dev_pm_detach() in acpi.h
ACPI / video: ignore BIOS initial backlight value for HP Folio 13-2000
ACPI : do not use Lid and Sleep button for S5 wakeup
ACPI / PNP: Do not crash due to stale pointer use during system resume
ACPI / video: Add "Asus UL30VT" to ACPI video detect blacklist
ACPI: do acpisleep dmi check when CONFIG_ACPI_SLEEP is set
spi / ACPI: add ACPI enumeration support
gpio / ACPI: add ACPI support
PM / devfreq: remove compiler error with module governors (2)
cpupower: IvyBridge (0x3a and 0x3e models) support
cpupower: Provide -c param for cpupower monitor to schedule process on all cores
cpupower tools: Fix warning and a bug with the cpu package count
cpupower tools: Fix malloc of cpu_info structure
cpupower tools: Fix issues with sysfs_topology_read_file
cpupower tools: Fix minor warnings
cpupower tools: Update .gitignore for files created in the debug directories
...
This patch provides a way to VMCLEAR VMCSs related to guests
on all cpus before executing the VMXOFF when doing kdump. This
is used to ensure the VMCSs in the vmcore updated and
non-corrupted.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
EFI provides support for providing PCI ROMs via means other than the ROM
BAR. This support vanishes after we've exited boot services, so add support
for stashing copies of the ROMs in setup_data if they're not otherwise
available.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Bit24 in VMX_EPT_VPID_CAP_MASI is not used for address-specific invalidation capability
reporting, so remove it from KVM to avoid conflicts in future.
Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Conflicts:
arch/x86/kernel/ptrace.c
Pull the latest RCU tree from Paul E. McKenney:
" The major features of this series are:
1. A first version of no-callbacks CPUs. This version prohibits
offlining CPU 0, but only when enabled via CONFIG_RCU_NOCB_CPU=y.
Relaxing this constraint is in progress, but not yet ready
for prime time. These commits were posted to LKML at
https://lkml.org/lkml/2012/10/30/724, and are at branch rcu/nocb.
2. Changes to SRCU that allows statically initialized srcu_struct
structures. These commits were posted to LKML at
https://lkml.org/lkml/2012/10/30/296, and are at branch rcu/srcu.
3. Restructuring of RCU's debugfs output. These commits were posted
to LKML at https://lkml.org/lkml/2012/10/30/341, and are at
branch rcu/tracing.
4. Additional CPU-hotplug/RCU improvements, posted to LKML at
https://lkml.org/lkml/2012/10/30/327, and are at branch rcu/hotplug.
Note that the commit eliminating __stop_machine() was judged to
be too-high of risk, so is deferred to 3.9.
5. Changes to RCU's idle interface, most notably a new module
parameter that redirects normal grace-period operations to
their expedited equivalents. These were posted to LKML at
https://lkml.org/lkml/2012/10/30/739, and are at branch rcu/idle.
6. Additional diagnostics for RCU's CPU stall warning facility,
posted to LKML at https://lkml.org/lkml/2012/10/30/315, and
are at branch rcu/stall. The most notable change reduces the
default RCU CPU stall-warning time from 60 seconds to 21 seconds,
so that it once again happens sooner than the softlockup timeout.
7. Documentation updates, which were posted to LKML at
https://lkml.org/lkml/2012/10/30/280, and are at branch rcu/doc.
A couple of late-breaking changes were posted at
https://lkml.org/lkml/2012/11/16/634 and
https://lkml.org/lkml/2012/11/16/547.
8. Miscellaneous fixes, which were posted to LKML at
https://lkml.org/lkml/2012/10/30/309, along with a late-breaking
change posted at Fri, 16 Nov 2012 11:26:25 -0800 with message-ID
<20121116192625.GA447@linux.vnet.ibm.com>, but which lkml.org
seems to have missed. These are at branch rcu/fixes.
9. Finally, a fix for an lockdep-RCU splat was posted to LKML
at https://lkml.org/lkml/2012/11/7/486. This is at rcu/next. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf fixes from Ingo Molnar:
"This is mostly about unbreaking architectures that took the UAPI
changes in the v3.7 cycle, plus misc fixes."
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf kvm: Fix building perf kvm on non x86 arches
perf kvm: Rename perf_kvm to perf_kvm_stat
perf: Make perf build for x86 with UAPI disintegration applied
perf powerpc: Use uapi/unistd.h to fix build error
tools: Pass the target in descend
tools: Honour the O= flag when tool build called from a higher Makefile
tools: Define a Makefile function to do subdir processing
x86: Export asm/{svm.h,vmx.h,perf_regs.h}
perf tools: Fix strbuf_addf() when the buffer needs to grow
perf header: Fix numa topology printing
perf, powerpc: Fix hw breakpoints returning -ENOSPC
When a cpu enters S3 state, the FPU state is lost.
After resuming for S3, if we try to lazy restore the FPU for a process running
on the same CPU, this will result in a corrupted FPU context.
Ensure that "fpu_owner_task" is properly invalided when (re-)initializing a CPU,
so nobody will try to lazy restore a state which doesn't exist in the hardware.
Tested with a 64-bit kernel on a 4-core Ivybridge CPU with eagerfpu=off,
by doing thousands of suspend/resume cycles with 4 processes doing FPU
operations running. Without the patch, a process is killed after a
few hundreds cycles by a SIGFPE.
Cc: Duncan Laurie <dlaurie@chromium.org>
Cc: Olof Johansson <olofj@chromium.org>
Cc: <stable@kernel.org> v3.4+ # for 3.4 need to replace this_cpu_write by percpu_write
Signed-off-by: Vincent Palatin <vpalatin@chromium.org>
Link: http://lkml.kernel.org/r/1354306532-1014-1-git-send-email-vpalatin@chromium.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
CPUID.7.0.EBX[1]=1 indicates IA32_TSC_ADJUST MSR 0x3b is supported
Basic design is to emulate the MSR by allowing reads and writes to a guest
vcpu specific location to store the value of the emulated MSR while adding
the value to the vmcs tsc_offset. In this way the IA32_TSC_ADJUST value will
be included in all reads to the TSC MSR whether through rdmsr or rdtsc. This
is of course as long as the "use TSC counter offsetting" VM-execution control
is enabled as well as the IA32_TSC_ADJUST control.
However, because hardware will only return the TSC + IA32_TSC_ADJUST +
vmsc tsc_offset for a guest process when it does and rdtsc (with the correct
settings) the value of our virtualized IA32_TSC_ADJUST must be stored in one
of these three locations. The argument against storing it in the actual MSR
is performance. This is likely to be seldom used while the save/restore is
required on every transition. IA32_TSC_ADJUST was created as a way to solve
some issues with writing TSC itself so that is not an option either.
The remaining option, defined above as our solution has the problem of
returning incorrect vmcs tsc_offset values (unless we intercept and fix, not
done here) as mentioned above. However, more problematic is that storing the
data in vmcs tsc_offset will have a different semantic effect on the system
than does using the actual MSR. This is illustrated in the following example:
The hypervisor set the IA32_TSC_ADJUST, then the guest sets it and a guest
process performs a rdtsc. In this case the guest process will get
TSC + IA32_TSC_ADJUST_hyperviser + vmsc tsc_offset including
IA32_TSC_ADJUST_guest. While the total system semantics changed the semantics
as seen by the guest do not and hence this will not cause a problem.
Signed-off-by: Will Auld <will.auld@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
In order to track who initiated the call (host or guest) to modify an msr
value I have changed function call parameters along the call path. The
specific change is to add a struct pointer parameter that points to (index,
data, caller) information rather than having this information passed as
individual parameters.
The initial use for this capability is for updating the IA32_TSC_ADJUST msr
while setting the tsc value. It is anticipated that this capability is
useful for other tasks.
Signed-off-by: Will Auld <will.auld@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Create a new subsystem that probes on kernel boundaries
to keep track of the transitions between level contexts
with two basic initial contexts: user or kernel.
This is an abstraction of some RCU code that use such tracking
to implement its userspace extended quiescent state.
We need to pull this up from RCU into this new level of indirection
because this tracking is also going to be used to implement an "on
demand" generic virtual cputime accounting. A necessary step to
shutdown the tick while still accounting the cputime.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Gilad Ben-Yossef <gilad@benyossef.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
[ paulmck: fix whitespace error and email address. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Simplify the implementation of sync_core() for the case where we may
not have the CPUID instruction available.
[ v2: stylistic cleanup of the #else clause per suggestion by Borislav
Petkov. ]
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1354132230-21854-9-git-send-email-hpa@linux.intel.com
Cc: Borislav Petkov <bp@alien8.de>
We use XENMEM_add_to_physmap_range which is the preferred interface
for foreign mappings.
Acked-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
With master clock, a pvclock clock read calculates:
ret = system_timestamp + [ (rdtsc + tsc_offset) - tsc_timestamp ]
Where 'rdtsc' is the host TSC.
system_timestamp and tsc_timestamp are unique, one tuple
per VM: the "master clock".
Given a host with synchronized TSCs, its obvious that
guest TSC must be matched for the above to guarantee monotonicity.
Allow master clock usage only if guest TSCs are synchronized.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
KVM added a global variable to guarantee monotonicity in the guest.
One of the reasons for that is that the time between
1. ktime_get_ts(×pec);
2. rdtscll(tsc);
Is variable. That is, given a host with stable TSC, suppose that
two VCPUs read the same time via ktime_get_ts() above.
The time required to execute 2. is not the same on those two instances
executing in different VCPUS (cache misses, interrupts...).
If the TSC value that is used by the host to interpolate when
calculating the monotonic time is the same value used to calculate
the tsc_timestamp value stored in the pvclock data structure, and
a single <system_timestamp, tsc_timestamp> tuple is visible to all
vcpus simultaneously, this problem disappears. See comment on top
of pvclock_update_vm_gtod_copy for details.
Monotonicity is then guaranteed by synchronicity of the host TSCs
and guest TSCs.
Set TSC stable pvclock flag in that case, allowing the guest to read
clock from userspace.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Improve performance of time system calls when using Linux pvclock,
by reading time info from fixmap visible copy of pvclock data.
Originally from Jeremy Fitzhardinge.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Hook into generic pvclock vsyscall code, with the aim to
allow userspace to have visibility into pvclock data.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>