James Simmons [Mon, 11 Jul 2016 13:40:10 +0000 (09:40 -0400)]
staging: lustre: llite: basic port to xattr_handler API
Port the xattr functionality to the new xattr_handler API.
This is smallest changes needed to move to this new API. The
function ll_removexattr can be replaced by generic_removexattr
as well since it also uses the xattr_handler set xattr backend.
To tell the difference between the two cases we test the flag
passed in for XATTR_REPLACE. The ll_getxattr function is
replaced by the generic_getxattr function.
Signed-off-by: James Simmons <jsimmons@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
James Simmons [Mon, 20 Jun 2016 22:47:50 +0000 (18:47 -0400)]
staging: lustre: llite: break ll_getxattr_common into 2 functions
Split the function ll_getxattr_common into two functions.
The code used for listing xattrs and ll_getxattr_common is
placed into a new function ll_getxattr_list. This allows
ll_listxattr to call directly ll_getxattr_list instead of
going through ll_getxattr_common. This change is needed
for the upcoming VFS move xattr_handler from [s|g]etxattr.
Signed-off-by: James Simmons <jsimmons@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The workqueue is being used to run deferred work for the android binder.
The "binder_deferred_workqueue" queues only a single work item and hence
does not require ordering. Also, this workqueue is not being used on a
memory recliam path. Hence, the singlethreaded workqueue has been
replaced with the use of system_wq.
System workqueues have been able to handle high level of concurrency
for a long time now and hence it's not required to have a singlethreaded
workqueue just to gain concurrency. Unlike a dedicated per-cpu workqueue
created with create_singlethread_workqueue(), system_wq allows multiple
work items to overlap executions even on the same CPU; however, a
per-cpu workqueue doesn't have any CPU locality or global ordering
guarantee unless the target CPU is explicitly specified and thus the
increase of local concurrency shouldn't make any difference.
Gustavo Padovan [Thu, 11 Aug 2016 15:26:44 +0000 (12:26 -0300)]
dma-buf/sw_sync: de-stage SW_SYNC
SW_SYNC allows to run tests on the sync_file framework via debugfs on
<debugfs>/sync/sw_sync
Opening and closing the file triggers creation and release of a sync
timeline. To create fences on this timeline the SW_SYNC_IOC_CREATE_FENCE
ioctl should be used. To increment the timeline value use SW_SYNC_IOC_INC.
Gustavo Padovan [Thu, 11 Aug 2016 16:45:53 +0000 (13:45 -0300)]
staging/android: add Doc for SW_SYNC ioctl interface
This interface is hidden from kernel headers and it is intended for use
only for testing. So testers would have to add the ioctl information
internally. This is to prevent misuse of this feature.
v2: take in Eric suggestions for the Documentation
Gustavo Padovan [Thu, 11 Aug 2016 15:26:40 +0000 (12:26 -0300)]
staging/android: do not let userspace trigger WARN_ON
Closing the timeline without waiting all fences to signal is not
a critical failure, it is just bad usage from userspace so avoid
calling WARN_ON in this case.
Laura Abbott [Mon, 8 Aug 2016 16:52:58 +0000 (09:52 -0700)]
staging: android: ion: Get rid of ion_reserve
ion_reserve was supposed to be used to reserve memory in board files.
These days, board files are no more and there are other more controlled
mechanisms for reserving memory. Get rid of this function.
Signed-off-by: Laura Abbott <labbott@redhat.com> Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Laura Abbott [Mon, 8 Aug 2016 16:52:56 +0000 (09:52 -0700)]
staging: android: ion: Get rid of map_dma/unmap_dma
The map_dma API interface was designed to generate an sg_table.
Currently, every client just creates the table at allocation time and
then returns the one table. Nothing happens on unmap_dma either.
Just get rid of the API and assign the sg_table directly.
Signed-off-by: Laura Abbott <labbott@redhat.com> Reviewed-by: Benjamin Gaignard <benjamin.gaignard@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Colin Ian King [Sat, 13 Aug 2016 18:52:38 +0000 (19:52 +0100)]
staging: ks7010: do not dereference priv if priv is null
priv is being dereferenced before a check for it being null
is made, so there is a possibililty a null pointer deference
can occur. Instead, only dereference priv if it is non-null.
Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Markus Elfring [Sun, 17 Jul 2016 11:38:46 +0000 (13:38 +0200)]
staging: ks7010: Delete unnecessary assignments for buffer variables
A few variables were assigned a null pointer despite of the detail
that they were immediately reassigned by the following statement.
Thus remove such unnecessary assignments.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linus Torvalds [Mon, 15 Aug 2016 02:01:31 +0000 (19:01 -0700)]
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal updates from Zhang Rui:
- Fix a race condition when updating cooling device, which may lead to
a situation where a thermal governor never updates the cooling
device. From Michele Di Giorgio.
- Fix a zero division error when disabling the forced idle injection
from the intel powerclamp. From Petr Mladek.
- Add suspend/resume callback for intel_pch_thermal thermal driver.
From Srinivas Pandruvada.
- Another two fixes for clocking cooling driver and hwmon sysfs I/F.
From Michele Di Giorgio and Kuninori Morimoto.
[ Hmm. That suspend/resume callback for intel_pch_thermal doesn't look
like a fix, but I'm letting it slide.. - Linus ]
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal: clock_cooling: Fix missing mutex_init()
thermal: hwmon: EXPORT_SYMBOL_GPL for thermal hwmon sysfs
thermal: fix race condition when updating cooling device
thermal/powerclamp: Prevent division by zero when counting interval
thermal: intel_pch_thermal: Add suspend/resume callback
Linus Torvalds [Mon, 15 Aug 2016 01:54:37 +0000 (18:54 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
Pull m68knommu fix from Greg Ungerer:
"This contains only a single fix for a register corruption problem on
certain types of m68k flat format binaries"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68knommu: fix user a5 register being overwritten
Linus Torvalds [Sun, 14 Aug 2016 02:39:38 +0000 (19:39 -0700)]
Merge tag 'fixes-for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull h8300 and unicore32 architecture fixes from Guenter Roeck:
"Two patches to fix h8300 and unicore32 builds.
unicore32 builds have been broken since v4.6. The fix has been
available in -next since March of this year.
h8300 builds have been broken since the last commit window. The fix
has been available in -next since June of this year"
* tag 'fixes-for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
h8300: Add missing include file to asm/io.h
unicore32: mm: Add missing parameter to arch_vma_access_permitted
Linus Torvalds [Sat, 13 Aug 2016 16:56:45 +0000 (09:56 -0700)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- an NVMe fix from Gabriel, fixing a suspend/resume issue on some
setups
- addition of a few missing entries in the block queue sysfs
documentation, from Joe
- a fix for a sparse shadow warning for the bvec iterator, from
Johannes
- a writeback deadlock involving raid issuing barriers, and not
flushing the plug when we wakeup the flusher threads. From
Konstantin
- a set of patches for the NVMe target/loop/rdma code, from Roland and
Sagi
* 'for-linus' of git://git.kernel.dk/linux-block:
bvec: avoid variable shadowing warning
doc: update block/queue-sysfs.txt entries
nvme: Suspend all queues before deletion
mm, writeback: flush plugged IO in wakeup_flusher_threads()
nvme-rdma: Remove unused includes
nvme-rdma: start async event handler after reconnecting to a controller
nvmet: Fix controller serial number inconsistency
nvmet-rdma: Don't use the inline buffer in order to avoid allocation for small reads
nvmet-rdma: Correctly handle RDMA device hot removal
nvme-rdma: Make sure to shutdown the controller if we can
nvme-loop: Remove duplicate call to nvme_remove_namespaces
nvme-rdma: Free the I/O tags when we delete the controller
nvme-rdma: Remove duplicate call to nvme_remove_namespaces
nvme-rdma: Fix device removal handling
nvme-rdma: Queue ns scanning after a sucessful reconnection
nvme-rdma: Don't leak uninitialized memory in connect request private data
Guenter Roeck [Thu, 9 Jun 2016 03:11:58 +0000 (20:11 -0700)]
h8300: Add missing include file to asm/io.h
h8300 builds fail with
arch/h8300/include/asm/io.h:9:15: error: unknown type name ‘u8’
arch/h8300/include/asm/io.h:15:15: error: unknown type name ‘u16’
arch/h8300/include/asm/io.h:21:15: error: unknown type name ‘u32’
Guenter Roeck [Mon, 21 Mar 2016 11:20:53 +0000 (04:20 -0700)]
unicore32: mm: Add missing parameter to arch_vma_access_permitted
unicore32 fails to compile with the following errors.
mm/memory.c: In function ‘__handle_mm_fault’:
mm/memory.c:3381: error:
too many arguments to function ‘arch_vma_access_permitted’
mm/gup.c: In function ‘check_vma_flags’:
mm/gup.c:456: error:
too many arguments to function ‘arch_vma_access_permitted’
mm/gup.c: In function ‘vma_permits_fault’:
mm/gup.c:640: error:
too many arguments to function ‘arch_vma_access_permitted’
Linus Torvalds [Fri, 12 Aug 2016 23:28:41 +0000 (16:28 -0700)]
Merge tag 'nfsd-4.8-1' of git://linux-nfs.org/~bfields/linux
Pull nfsd fixes from Bruce Fields:
"Fixes for the dentry refcounting leak I introduced in 4.8-rc1, and for
races in the LOCK code which appear to go back to the big nfsd state
lock removal from 3.17"
* tag 'nfsd-4.8-1' of git://linux-nfs.org/~bfields/linux:
nfsd: don't return an unhashed lock stateid after taking mutex
nfsd: Fix race between FREE_STATEID and LOCK
nfsd: fix dentry refcounting on create
Linus Torvalds [Fri, 12 Aug 2016 23:23:58 +0000 (16:23 -0700)]
Merge tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Two hibernation fixes allowing it to work with the recently added
randomization of the kernel identity mapping base on x86-64 and one
cpufreq driver regression fix.
Specifics:
- Fix the x86 identity mapping creation helpers to avoid the
assumption that the base address of the mapping will always be
aligned at the PGD level, as it may be aligned at the PUD level if
address space randomization is enabled (Rafael Wysocki).
- Fix the hibernation core to avoid executing tracing functions
before restoring the processor state completely during resume
(Thomas Garnier).
- Fix a recently introduced regression in the powernv cpufreq driver
that causes it to crash due to an out-of-bounds array access
(Akshay Adiga)"
* tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / hibernate: Restore processor state before using per-CPU variables
x86/power/64: Always create temporary identity mapping correctly
cpufreq: powernv: Fix crash in gpstate_timer_handler()
Linus Torvalds [Fri, 12 Aug 2016 21:31:10 +0000 (14:31 -0700)]
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"This is bigger than usual - the reason is partly a pent-up stream of
fixes after the merge window and partly accidental. The fixes are:
- five patches to fix a boot failure on Andy Lutomirsky's laptop
- four SGI UV platform fixes
- KASAN fix
- warning fix
- documentation update
- swap entry definition fix
- pkeys fix
- irq stats fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe()
x86/efi: Allocate a trampoline if needed in efi_free_boot_services()
x86/boot: Rework reserve_real_mode() to allow multiple tries
x86/boot: Defer setup_real_mode() to early_initcall time
x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly
x86/boot: Run reserve_bios_regions() after we initialize the memory map
x86/irq: Do not substract irq_tlb_count from irq_call_count
x86/mm: Fix swap entry comment and macro
x86/mm/kaslr: Fix -Wformat-security warning
x86/mm/pkeys: Fix compact mode by removing protection keys' XSAVE buffer manipulation
x86/build: Reduce the W=1 warnings noise when compiling x86 syscall tables
x86/platform/UV: Fix kernel panic running RHEL kdump kernel on UV systems
x86/platform/UV: Fix problem with UV4 BIOS providing incorrect PXM values
x86/platform/UV: Fix bug with iounmap() of the UV4 EFI System Table causing a crash
x86/platform/UV: Fix problem with UV4 Socket IDs not being contiguous
x86/entry: Clarify the RF saving/restoring situation with SYSCALL/SYSRET
x86/mm: Disable preemption during CR3 read+write
x86/mm/KASLR: Increase BRK pages for KASLR memory randomization
x86/mm/KASLR: Fix physical memory calculation on KASLR memory randomization
x86, kasan, ftrace: Put APIC interrupt handlers into .irqentry.text
Linus Torvalds [Fri, 12 Aug 2016 20:55:06 +0000 (13:55 -0700)]
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Ingo Molnar:
"Misc fixes: a /dev/rtc regression fix, two APIC timer period
calibration fixes, an ARM clocksource driver fix and a NOHZ
power use regression fix"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/hpet: Fix /dev/rtc breakage caused by RTC cleanup
x86/timers/apic: Inform TSC deadline clockevent device about recalibration
x86/timers/apic: Fix imprecise timer interrupts by eliminating TSC clockevents frequency roundoff error
timers: Fix get_next_timer_interrupt() computation
clocksource/arm_arch_timer: Force per-CPU interrupt to be level-triggered
Thomas Garnier [Thu, 11 Aug 2016 21:49:29 +0000 (14:49 -0700)]
PM / hibernate: Restore processor state before using per-CPU variables
Restore the processor state before calling any other functions to
ensure per-CPU variables can be used with KASLR memory randomization.
Tracing functions use per-CPU variables (GS based on x86) and one was
called just before restoring the processor state fully. It resulted
in a double fault when both the tracing & the exception handler
functions tried to use a per-CPU variable.
Fixes: bb3632c6101b (PM / sleep: trace events for suspend/resume) Reported-and-tested-by: Borislav Petkov <bp@suse.de> Reported-by: Jiri Kosina <jikos@kernel.org> Tested-by: Rafael J. Wysocki <rafael@kernel.org> Tested-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Thomas Garnier <thgarnie@google.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Linus Torvalds [Fri, 12 Aug 2016 20:21:18 +0000 (13:21 -0700)]
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, plus two uncore-PMU fixes, an uprobes fix, a
perf-cgroups fix and an AUX events fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Add enable_box for client MSR uncore
perf/x86/intel/uncore: Fix uncore num_counters
uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions
perf/core: Set cgroup in CPU contexts for new cgroup events
perf/core: Fix sideband list-iteration vs. event ordering NULL pointer deference crash
perf probe ppc64le: Fix probe location when using DWARF
perf probe: Add function to post process kernel trace events
tools: Sync cpufeatures headers with the kernel
toops: Sync tools/include/uapi/linux/bpf.h with the kernel
tools: Sync cpufeatures.h and vmx.h with the kernel
perf probe: Support signedness casting
perf stat: Avoid skew when reading events
perf probe: Fix module name matching
perf probe: Adjust map->reloc offset when finding kernel symbol from map
perf hists: Trim libtraceevent trace_seq buffers
perf script: Add 'bpf-output' field to usage message
Jeff Layton [Thu, 11 Aug 2016 14:37:39 +0000 (10:37 -0400)]
nfsd: don't return an unhashed lock stateid after taking mutex
nfsd4_lock will take the st_mutex before working with the stateid it
gets, but between the time when we drop the cl_lock and take the mutex,
the stateid could become unhashed (a'la FREE_STATEID). If that happens
the lock stateid returned to the client will be forgotten.
Fix this by first moving the st_mutex acquisition into
lookup_or_create_lock_state. Then, have it check to see if the lock
stateid is still hashed after taking the mutex. If it's not, then put
the stateid and try the find/create again.
Signed-off-by: Jeff Layton <jlayton@redhat.com> Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> Cc: stable@vger.kernel.org # feb9dad5 nfsd: Always lock state exclusively. Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Linus Torvalds [Fri, 12 Aug 2016 19:46:37 +0000 (12:46 -0700)]
Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
"Misc fixes: lockstat fix, futex fix on !MMU systems, big endian fix
for qrwlocks and a race fix for pvqspinlocks"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/pvqspinlock: Fix a bug in qstat_read()
locking/pvqspinlock: Fix double hash race
locking/qrwlock: Fix write unlock bug on big endian systems
futex: Assume all mappings are private on !MMU systems
Linus Torvalds [Fri, 12 Aug 2016 19:39:02 +0000 (12:39 -0700)]
Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI fixes from Ingo Molnar:
"A fix for EFI capsules and an SGI UV platform fix"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi/capsule: Allocate whole capsule into virtual memory
x86/platform/uv: Skip UV runtime services mapping in the efi_runtime_disabled case
Linus Torvalds [Fri, 12 Aug 2016 19:32:24 +0000 (12:32 -0700)]
Merge tag 'nfs-for-4.8-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
- Stable patch from Olga to fix RPCSEC_GSS upcalls when the same user
needs multiple different security services (e.g. krb5i and krb5p).
- Stable patch to fix a regression introduced by the use of
SO_REUSEPORT, and that prevented the use of multiple different NFS
versions to the same server.
- TCP socket reconnection timer fixes.
- Patch from Neil to disable the use of IPv6 temporary addresses"
* tag 'nfs-for-4.8-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Cap the transport reconnection timer at 1/2 lease period
NFSv4: Cleanup the setting of the nfs4 lease period
SUNRPC: Limit the reconnect backoff timer to the max RPC message timeout
SUNRPC: Fix reconnection timeouts
NFSv4.2: LAYOUTSTATS may return NFS4ERR_ADMIN/DELEG_REVOKED
SUNRPC: disable the use of IPv6 temporary addresses.
SUNRPC: allow for upcalls for same uid but different gss service
SUNRPC: Fix up socket autodisconnect
SUNRPC: Handle EADDRNOTAVAIL on connection failures
Linus Torvalds [Fri, 12 Aug 2016 19:28:23 +0000 (12:28 -0700)]
Merge branch 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm fixes from Dan Williams:
- Fix for the nd_blk (NVDIMM Block Window Aperture) driver.
A spec clarification requires the driver to mask off reserved bits in
status register. This is tagged for -stable back to the v4.2 kernel.
- Fix for a kernel crash in the nvdimm unit tests when module loading
is interrupted with SIGTERM. Tagged for -stable since validation
efforts external to Intel use the unit tests for qualifying
backports.
- Add a new 'size' sysfs attribute for the BTT (NVDIMM Block
Translation Table) driver to make it symmetric with the other
namespace personality drivers (PFN and DAX) that provide a size
attribute for indicating how much namespace capacity is lost to
metadata.
The BTT change arrived at the start of the merge window and has
appeared in a -next release. It can technically wait for 4.9, but it
is small, fixes asymmetry in the libnvdimm-sysfs interface, and
something I would have squeezed into the v4.8 pull request had it
arrived a few days earlier.
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
tools/testing/nvdimm: fix SIGTERM vs hotplug crash
nvdimm, btt: add a size attribute for BTTs
libnvdimm, nd_blk: mask off reserved status bits
Linus Torvalds [Fri, 12 Aug 2016 19:26:59 +0000 (12:26 -0700)]
Merge tag 'sound-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A regression fix of HD-audio runtime PM and two USB quirks"
* tag 'sound-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda - Manage power well properly for resume
ALSA: usb-audio: Add quirk for ELP HD USB Camera
ALSA: usb-audio: Add a sample rate quirk for Creative Live! Cam Socialize HD (VF0610)
Linus Torvalds [Fri, 12 Aug 2016 19:09:44 +0000 (12:09 -0700)]
Merge tag 'powerpc-4.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Some powerpc fixes for 4.8:
Misc:
- powerpc/vdso: Fix build rules to rebuild vdsos correctly from Nicholas Piggin
- powerpc/ptrace: Fix coredump since ptrace TM changes from Cyril Bur
- powerpc/32: Fix csum_partial_copy_generic() from Christophe Leroy
- cxl: Set psl_fir_cntl to production environment value from Frederic Barrat
- powerpc/eeh: Switch to conventional PCI address output in EEH log from Guilherme G. Piccoli
- cxl: Use fixed width predefined types in data structure. from Philippe Bergheaud
- powerpc/vdso: Add missing include file from Guenter Roeck
- powerpc: Fix unused function warning 'lmb_to_memblock' from Alastair D'Silva
- powerpc/powernv/ioda: Fix TCE invalidate to work in real mode again from Alexey Kardashevskiy
- powerpc/cell: Add missing error code in spufs_mkgang() from Dan Carpenter
- crypto: crc32c-vpmsum - Convert to CPU feature based module autoloading from Anton Blanchard
- powerpc/pasemi: Fix coherent_dma_mask for dma engine from Darren Stevens
Benjamin Herrenschmidt:
- powerpc/32: Fix crash during static key init
- powerpc: Update obsolete comment in setup_32.c about early_init()
- powerpc: Print the kernel load address at the end of prom_init()
- powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs
- powerpc/xics: Properly set Edge/Level type and enable resend
Mahesh Salgaonkar:
- powerpc/book3s: Fix MCE console messages for unrecoverable MCE.
- powerpc/powernv: Fix MCE handler to avoid trashing CR0/CR1 registers.
- powerpc/powernv: Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h
- powerpc/powernv: Load correct TOC pointer while waking up from winkle.
Andrew Donnellan:
- cxl: Fix sparse warnings
- cxl: Fix NULL dereference in cxl_context_init() on PowerVM guests
Michael Ellerman:
- selftests/powerpc: Specify we expect to build with std=gnu99
- powerpc/Makefile: Use cflags-y/aflags-y for setting endian options
- powerpc/pci: Fix endian bug in fixed PHB numbering"
* tag 'powerpc-4.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (26 commits)
selftests/powerpc: Specify we expect to build with std=gnu99
powerpc/vdso: Fix build rules to rebuild vdsos correctly
powerpc/Makefile: Use cflags-y/aflags-y for setting endian options
powerpc/32: Fix crash during static key init
powerpc: Update obsolete comment in setup_32.c about early_init()
powerpc: Print the kernel load address at the end of prom_init()
powerpc/ptrace: Fix coredump since ptrace TM changes
powerpc/32: Fix csum_partial_copy_generic()
cxl: Set psl_fir_cntl to production environment value
powerpc/pnv/pci: Fix incorrect PE reservation attempt on some 64-bit BARs
powerpc/book3s: Fix MCE console messages for unrecoverable MCE.
powerpc/pci: Fix endian bug in fixed PHB numbering
powerpc/eeh: Switch to conventional PCI address output in EEH log
cxl: Fix sparse warnings
cxl: Fix NULL dereference in cxl_context_init() on PowerVM guests
cxl: Use fixed width predefined types in data structure.
powerpc/vdso: Add missing include file
powerpc: Fix unused function warning 'lmb_to_memblock'
powerpc/powernv: Fix MCE handler to avoid trashing CR0/CR1 registers.
powerpc/powernv: Move IDLE_STATE_ENTER_SEQ macro to cpuidle.h
...
Riku Voipio [Wed, 15 Jun 2016 08:27:59 +0000 (11:27 +0300)]
arm64: defconfig: add options for virtualization and containers
Enable options commonly needed by popular virtualization
and container applications. Use modules when possible to
avoid too much overhead for users not interested.
- add namespace and cgroup options needed
- add seccomp - optional, but enhances Qemu etc
- bridge, nat, veth, macvtap and multicast for routing
guests and containers
- btfrs and overlayfs modules for container COW backends
- while near it, make fuse a module instead of built-in.
Generated with make saveconfig and dropping unrelated spurious
change hunks while commiting. bloat-o-meter old-vmlinux vmlinux:
Mark Rutland [Thu, 11 Aug 2016 13:11:06 +0000 (14:11 +0100)]
arm64: hibernate: handle allocation failures
In create_safe_exec_page(), we create a copy of the hibernate exit text,
along with some page tables to map this via TTBR0. We then install the
new tables in TTBR0.
In swsusp_arch_resume() we call create_safe_exec_page() before trying a
number of operations which may fail (e.g. copying the linear map page
tables). If these fail, we bail out of swsusp_arch_resume() and return
an error code, but leave TTBR0 as-is. Subsequently, the core hibernate
code will call free_basic_memory_bitmaps(), which will free all of the
memory allocations we made, including the page tables installed in
TTBR0.
Thus, we may have TTBR0 pointing at dangling freed memory for some
period of time. If the hibernate attempt was triggered by a user
requesting a hibernate test via the reboot syscall, we may return to
userspace with the clobbered TTBR0 value.
Avoid these issues by reorganising swsusp_arch_resume() such that we
have no failure paths after create_safe_exec_page(). We also add a check
that the zero page allocation succeeded, matching what we have for other
allocations.
Fixes: 82869ac57b5d ("arm64: kernel: Add support for hibernate/suspend-to-disk") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: James Morse <james.morse@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> # 4.7+ Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Mark Rutland [Thu, 11 Aug 2016 13:11:05 +0000 (14:11 +0100)]
arm64: hibernate: avoid potential TLB conflict
In create_safe_exec_page we install a set of global mappings in TTBR0,
then subsequently invalidate TLBs. While TTBR0 points at the zero page,
and the TLBs should be free of stale global entries, we may have stale
ASID-tagged entries (e.g. from the EFI runtime services mappings) for
the same VAs. Per the ARM ARM these ASID-tagged entries may conflict
with newly-allocated global entries, and we must follow a
Break-Before-Make approach to avoid issues resulting from this.
This patch reworks create_safe_exec_page to invalidate TLBs while the
zero page is still in place, ensuring that there are no potential
conflicts when the new TTBR0 value is installed. As a single CPU is
online while this code executes, we do not need to perform broadcast TLB
maintenance, and can call local_flush_tlb_all(), which also subsumes
some barriers. The remaining assembly is converted to use write_sysreg()
and isb().
Other than this, we safely manipulate TTBRs in the hibernate dance. The
code we install as part of the new TTBR0 mapping (the hibernated
kernel's swsusp_arch_suspend_exit) installs a zero page into TTBR1,
invalidates TLBs, then installs its preferred value. Upon being restored
to the middle of swsusp_arch_suspend, the new image will call
__cpu_suspend_exit, which will call cpu_uninstall_idmap, installing the
zero page in TTBR0 and invalidating all TLB entries.
Fixes: 82869ac57b5d ("arm64: kernel: Add support for hibernate/suspend-to-disk") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: James Morse <james.morse@arm.com> Tested-by: James Morse <james.morse@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> # 4.7+ Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Executing from a non-executable area gives an ugly message:
lkdtm: Performing direct entry EXEC_RODATA
lkdtm: attempting ok execution at ffff0000084c0e08
lkdtm: attempting bad execution at ffff000008880700
Bad mode in Synchronous Abort handler detected on CPU2, code 0x8400000e -- IABT (current EL)
CPU: 2 PID: 998 Comm: sh Not tainted 4.7.0-rc2+ #13
Hardware name: linux,dummy-virt (DT)
task: ffff800077e35780 ti: ffff800077970000 task.ti: ffff800077970000
PC is at lkdtm_rodata_do_nothing+0x0/0x8
LR is at execute_location+0x74/0x88
The 'IABT (current EL)' indicates the error but it's a bit cryptic
without knowledge of the ARM ARM. There is also no indication of the
specific address which triggered the fault. The increase in kernel
page permissions makes hitting this case more likely as well.
Handling the case in the vectors gives a much more familiar looking
error message:
Propagate errors from kvm_mips_handle_kseg0_tlb_fault() and
kvm_mips_handle_mapped_seg_tlb_fault(), usually triggering an internal
error since they normally indicate the guest accessed bad physical
memory or the commpage in an unexpected way.
James Hogan [Thu, 11 Aug 2016 10:58:13 +0000 (11:58 +0100)]
MIPS: KVM: Add missing gfn range check
kvm_mips_handle_mapped_seg_tlb_fault() calculates the guest frame number
based on the guest TLB EntryLo values, however it is not range checked
to ensure it lies within the guest_pmap. If the physical memory the
guest refers to is out of range then dump the guest TLB and emit an
internal error.
Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: <stable@vger.kernel.org> # 3.10.x- Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
kvm_mips_handle_mapped_seg_tlb_fault() appears to map the guest page at
virtual address 0 to PFN 0 if the guest has created its own mapping
there. The intention is unclear, but it may have been an attempt to
protect the zero page from being mapped to anything but the comm page in
code paths you wouldn't expect from genuine commpage accesses (guest
kernel mode cache instructions on that address, hitting trapping
instructions when executing from that address with a coincidental TLB
eviction during the KVM handling, and guest user mode accesses to that
address).
Fix this to check for mappings exactly at KVM_GUEST_COMMPAGE_ADDR (it
may not be at address 0 since commit 42aa12e74e91 ("MIPS: KVM: Move
commpage so 0x0 is unmapped")), and set the corresponding EntryLo to be
interpreted as 0 (invalid).
Fixes: 858dd5d45733 ("KVM/MIPS32: MMU/TLB operations for the Guest.") Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: <stable@vger.kernel.org> # 3.10.x- Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
KVM: Protect device ops->create and list_add with kvm->lock
KVM devices were manipulating list data structures without any form of
synchronization, and some implementations of the create operations also
suffered from a lack of synchronization.
Now when we've split the xics create operation into create and init, we
can hold the kvm->lock mutex while calling the create operation and when
manipulating the devices list.
The error path in the generic code gets slightly ugly because we have to
take the mutex again and delete the device from the list, but holding
the mutex during anon_inode_getfd or releasing/locking the mutex in the
common non-error path seemed wrong.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
As we are about to hold the kvm->lock during the create operation on KVM
devices, we should move the call to xics_debugfs_init into its own
function, since holding a mutex over extended amounts of time might not
be a good idea.
Introduce an init operation on the kvm_device_ops struct which cannot
fail and call this, if configured, after the device has been created.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
KVM: s390: reset KVM_REQ_MMU_RELOAD if mapping the prefix failed
When triggering KVM_RUN without a user memory region being mapped
(KVM_SET_USER_MEMORY_REGION) a validity intercept occurs. This could
happen, if the user memory region was not mapped initially or if it
was unmapped after the vcpu is initialized. The function
kvm_s390_handle_requests checks for the KVM_REQ_MMU_RELOAD bit. The
check function always clears this bit. If gmap_mprotect_notify
returns an error code, the mapping failed, but the KVM_REQ_MMU_RELOAD
was not set anymore. So the next time kvm_s390_handle_requests is
called, the execution would fall trough the check for
KVM_REQ_MMU_RELOAD. The bit needs to be resetted, if
gmap_mprotect_notify returns an error code. Resetting the bit with
kvm_make_request(KVM_REQ_MMU_RELOAD, vcpu) fixes the bug.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Julius Niedworok <jniedwor@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
When KVM_RUN is triggered on a VCPU without an initial reset, a
validity intercept occurs.
Setting the prefix will set the KVM_REQ_MMU_RELOAD bit initially,
thus preventing the bug.
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Julius Niedworok <jniedwor@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Kan Liang [Thu, 11 Aug 2016 14:31:14 +0000 (07:31 -0700)]
perf/x86/intel/uncore: Add enable_box for client MSR uncore
There are bug reports about miscounting uncore counters on some
client machines like Sandybridge, Broadwell and Skylake. It is
very likely to be observed on idle systems.
This issue is caused by a hardware issue. PERF_GLOBAL_CTL could be
cleared after Package C7, and nothing will be count.
The related errata (HSD 158) could be found in:
This patch tries to work around this issue by re-enabling PERF_GLOBAL_CTL
in ->enable_box(). The workaround does not cover all cases. It helps for new
events after returning from C7. But it cannot prevent C7, it will still
miscount if a counter is already active.
There is no drawback in leaving it enabled, so it does not need
disable_box() here.
Signed-off-by: Kan Liang <kan.liang@intel.com> Cc: <stable@vger.kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/1470925874-59943-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Kan Liang [Thu, 11 Aug 2016 14:30:20 +0000 (07:30 -0700)]
perf/x86/intel/uncore: Fix uncore num_counters
Some uncore boxes' num_counters value for Haswell server and
Broadwell server are not correct (too large, off by one).
This issue was found by comparing the code with the document. Although
there is no bug report from users yet, accessing non-existent counters
is dangerous and the behavior is undefined: it may cause miscounting or
even crashes.
This patch makes them consistent with the uncore document.
Reported-by: Lukasz Odzioba <lukasz.odzioba@intel.com> Signed-off-by: Kan Liang <kan.liang@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1470925820-59847-1-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Denys Vlasenko [Thu, 11 Aug 2016 15:45:21 +0000 (17:45 +0200)]
uprobes/x86: Fix RIP-relative handling of EVEX-encoded instructions
Since instruction decoder now supports EVEX-encoded instructions, two fixes
are needed to correctly handle them in uprobes.
Extended bits for MODRM.rm field need to be sanitized just like we do it
for VEX3, to avoid encoding wrong register for register-relative access.
EVEX has _two_ extended bits: b and x. Theoretically, EVEX.x should be
ignored by the CPU (since GPRs go only up to 15, not 31), but let's be
paranoid here: proper encoding for register-relative access
should have EVEX.x = 1.
Secondly, we should fetch vex.vvvv for EVEX too.
This is now super easy because instruction decoder populates
vex_prefix.bytes[2] for all flavors of (e)vex encodings, even for VEX2.
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: linux-kernel@vger.kernel.org Cc: <stable@vger.kernel.org> # v4.1+ Fixes: 8a764a875fe3 ("x86/asm/decoder: Create artificial 3rd byte for 2-byte VEX") Link: http://lkml.kernel.org/r/20160811154521.20469-1-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Linus Torvalds [Thu, 11 Aug 2016 23:58:24 +0000 (16:58 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
"7 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/memory_hotplug.c: initialize per_cpu_nodestats for hotadded pgdats
mm, oom: fix uninitialized ret in task_will_free_mem()
kasan: remove the unnecessary WARN_ONCE from quarantine.c
mm: memcontrol: fix memcg id ref counter on swap charge move
mm: memcontrol: fix swap counter leak on swapout from offline cgroup
proc, meminfo: use correct helpers for calculating LRU sizes in meminfo
mm/hugetlb: fix incorrect hugepages count during mem hotplug
kasan: remove the unnecessary WARN_ONCE from quarantine.c
It's quite unlikely that the user will so little memory that the per-CPU
quarantines won't fit into the given fraction of the available memory.
Even in that case he won't be able to do anything with the information
given in the warning.
Link: http://lkml.kernel.org/r/1470929182-101413-1-git-send-email-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kuthonuzo Luruo <kuthonuzo.luruo@hpe.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 11 Aug 2016 22:33:03 +0000 (15:33 -0700)]
mm: memcontrol: fix memcg id ref counter on swap charge move
Since commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure
after many small jobs") swap entries do not pin memcg->css.refcnt
directly. Instead, they pin memcg->id.ref. So we should adjust the
reference counters accordingly when moving swap charges between cgroups.
Fixes: 73f576c04b941 ("mm: memcontrol: fix cgroup creation failure after many small jobs") Link: http://lkml.kernel.org/r/9ce297c64954a42dc90b543bc76106c4a94f07e8.1470219853.git.vdavydov@virtuozzo.com Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: <stable@vger.kernel.org> [3.19+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 11 Aug 2016 22:33:00 +0000 (15:33 -0700)]
mm: memcontrol: fix swap counter leak on swapout from offline cgroup
An offline memory cgroup might have anonymous memory or shmem left
charged to it and no swap. Since only swap entries pin the id of an
offline cgroup, such a cgroup will have no id and so an attempt to
swapout its anon/shmem will not store memory cgroup info in the swap
cgroup map. As a result, memcg->swap or memcg->memsw will never get
uncharged from it and any of its ascendants.
Fix this by always charging swapout to the first ancestor cgroup that
hasn't released its id yet.
[hannes@cmpxchg.org: add comment to mem_cgroup_swapout]
[vdavydov@virtuozzo.com: use WARN_ON_ONCE() in mem_cgroup_id_get_online()] Link: http://lkml.kernel.org/r/20160803123445.GJ13263@esperanza Fixes: 73f576c04b941 ("mm: memcontrol: fix cgroup creation failure after many small jobs") Link: http://lkml.kernel.org/r/5336daa5c9a32e776067773d9da655d2dc126491.1470219853.git.vdavydov@virtuozzo.com Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> [3.19+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 11 Aug 2016 22:32:57 +0000 (15:32 -0700)]
proc, meminfo: use correct helpers for calculating LRU sizes in meminfo
meminfo_proc_show() and si_mem_available() are using the wrong helpers
for calculating the size of the LRUs. The user-visible impact is that
there appears to be an abnormally high number of unevictable pages.
Link: http://lkml.kernel.org/r/20160805105805.GR2799@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Cc: Dave Chinner <david@fromorbit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
zhong jiang [Thu, 11 Aug 2016 22:32:55 +0000 (15:32 -0700)]
mm/hugetlb: fix incorrect hugepages count during mem hotplug
When memory hotplug operates, free hugepages will be freed if the
movable node is offline. Therefore, /proc/sys/vm/nr_hugepages will be
incorrect.
Fix it by reducing max_huge_pages when the node is offlined.
n-horiguchi@ah.jp.nec.com said:
: dissolve_free_huge_page intends to break a hugepage into buddy, and the
: destination hugepage is supposed to be allocated from the pool of the
: destination node, so the system-wide pool size is reduced. So adding
: h->max_huge_pages-- makes sense to me.
Linus Torvalds [Thu, 11 Aug 2016 21:14:23 +0000 (14:14 -0700)]
Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC fixes from Arnd Bergmann:
"A couple of bug fixes have come in for v4.8 so far. Since the first
few were originally meant to go into -rc1 (but didn't get sent in time
for travel reasons), the branch is unfortunately based on top of a
commit in the middle of the merge window rather than -rc1.
Content-wise we have:
- a fix for the last remaining broken build in kernelci, getting
mach-shmobile to build again with SMP disabled
- a fix for a realview regression that broke real hardware but not
the qemu model that everyone uses in practice (needed for v4.7 as
well)
- a merge conflict fix for Tegra that also broke v4.7
- two Kconfig fixes for arm64 build regressions
- a couple of arm32 build warning fixes (all harmless)
- fix the RTC on Exynos7 Espresso (which apparently never worked
right)"
* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
Merge tag 'pxa-fixes-v4.8' of https://github.com/rjarzmik/linux into randconfig-4.8
arm64: Kconfig: select HISILICON_IRQ_MBIGEN only if PCI is selected
arm64: Kconfig: select ALPINE_MSI only if PCI is selected
ARM: dts: realview: Fix PBX-A9 cache description
ARM: tegra: fix erroneous address in dts
ARM: dts: add syscon compatible string for AP syscon
ARM: dts: add syscon compatible string for CP syscon
ARM: oxnas: select reset controller framework
ARM: hide mach-*/ include for ARM_SINGLE_ARMV7M
ARM: don't include removed directories
Revert "ARM: aspeed: adapt defconfigs for new CONFIG_PRINTK_TIME"
ARM: shmobile: don't call platform_can_secondary_boot on UP
MAINTAINER: alpine: add a mailing list
ARM: do away with final ARCH_REQUIRE_GPIOLIB
arm64: dts: Fix RTC by providing rtc_src clock
Linus Torvalds [Thu, 11 Aug 2016 21:10:23 +0000 (14:10 -0700)]
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio/vhost fixes and cleanups from Michael Tsirkin:
"Misc fixes and cleanups all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio/s390: deprecate old transport
virtio/s390: keep early_put_chars
virtio_blk: Fix a slient kernel panic
virtio-vsock: fix include guard typo
vhost/vsock: fix vhost virtio_vsock_pkt use-after-free
9p/trans_virtio: use kvfree() for iov_iter_get_pages_alloc()
virtio: fix error handling for debug builds
virtio: fix memory leak in virtqueue_add()
Linus Torvalds [Thu, 11 Aug 2016 20:53:34 +0000 (13:53 -0700)]
Merge tag 'ceph-for-4.8-rc2' of https://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"A patch for a NULL dereference bug introduced in 4.8-rc1 and a handful
of static checker fixes"
* tag 'ceph-for-4.8-rc2' of https://github.com/ceph/ceph-client:
ceph: initialize pathbase in the !dentry case in encode_caps_cb()
rbd: nuke the 32-bit pool id check
rbd: destroy header_oloc in rbd_dev_release()
ceph: fix null pointer dereference in ceph_flush_snaps()
libceph: using kfree_rcu() to simplify the code
libceph: make cancel_generic_request() static
libceph: fix return value check in alloc_msg_with_page_vector()
Chuck Lever [Thu, 11 Aug 2016 14:37:30 +0000 (10:37 -0400)]
nfsd: Fix race between FREE_STATEID and LOCK
When running LTP's nfslock01 test, the Linux client can send a LOCK
and a FREE_STATEID request at the same time. The outcome is:
Frame 324 R OPEN stateid [2,O]
Frame 115004 C LOCK lockowner_is_new stateid [2,O] offset 672000 len 64
Frame 115008 R LOCK stateid [1,L]
Frame 115012 C WRITE stateid [0,L] offset 672000 len 64
Frame 115016 R WRITE NFS4_OK
Frame 115019 C LOCKU stateid [1,L] offset 672000 len 64
Frame 115022 R LOCKU NFS4_OK
Frame 115025 C FREE_STATEID stateid [2,L]
Frame 115026 C LOCK lockowner_is_new stateid [2,O] offset 672128 len 64
Frame 115029 R FREE_STATEID NFS4_OK
Frame 115030 R LOCK stateid [3,L]
Frame 115034 C WRITE stateid [0,L] offset 672128 len 64
Frame 115038 R WRITE NFS4ERR_BAD_STATEID
In other words, the server returns stateid L in a successful LOCK
reply, but it has already released it. Subsequent uses of stateid L
fail.
To address this, protect the generation check in nfsd4_free_stateid
with the st_mutex. This should guarantee that only one of two
outcomes occurs: either LOCK returns a fresh valid stateid, or
FREE_STATEID returns NFS4ERR_LOCKS_HELD.
Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com> Fix-suggested-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Alexey Kodanev <alexey.kodanev@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
David A. Long [Wed, 10 Aug 2016 20:44:51 +0000 (16:44 -0400)]
arm64: Remove stack duplicating code from jprobes
Because the arm64 calling standard allows stacked function arguments to be
anywhere in the stack frame, do not attempt to duplicate the stack frame for
jprobes handler functions.
Documentation changes to describe this issue have been broken out into a
separate patch in order to simultaneously address them in other
architecture(s).
Signed-off-by: David A. Long <dave.long@linaro.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Josef Bacik [Wed, 10 Aug 2016 18:46:27 +0000 (14:46 -0400)]
nfsd: fix dentry refcounting on create
b44061d0b9 introduced a dentry ref counting bug. Previously we were
grabbing one ref to dchild in nfsd_create(), but with the creation of
nfsd_create_locked() we have a ref for dchild from the lookup in
nfsd_create(), and then another ref in nfsd_create_locked(). The ref
from the lookup in nfsd_create() is never dropped and results in
dentries still in use at unmount.
Signed-off-by: Josef Bacik <jbacik@fb.com> Fixes: b44061d0b9 "nfsd: reorganize nfsd_create" Reported-by: kernel test robot <xiaolong.ye@intel.com> Reviewed-by: Jeff Layton <jlayton@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When nvme_delete_queue fails in the first pass of the
nvme_disable_io_queues() loop, we return early, failing to suspend all
of the IO queues. Later, on the nvme_pci_disable path, this causes us
to disable MSI without actually having freed all the IRQs, which
triggers the BUG_ON in free_msi_irqs(), as show below.
This patch refactors nvme_disable_io_queues to suspend all queues before
start submitting delete queue commands. This way, we ensure that we
have at least returned every IRQ before continuing with the removal
path.
Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Cc: Brian King <brking@linux.vnet.ibm.com> Cc: Keith Busch <keith.busch@intel.com> Cc: linux-nvme@lists.infradead.org Signed-off-by: Jens Axboe <axboe@fb.com>
x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe()
I made a mistake while converting the driver to the hotplug state
machine and as a result x2apic_cluster_probe() was accessing
cpus_in_cluster before allocating it.
This patch fixes it by setting the cpumask after the allocation the
memory succeeded.
While at it, I marked two functions static which are only used within
this file.
Reported-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 6b2c28471de5 ("x86/x2apic: Convert to CPU hotplug state machine") Link: http://lkml.kernel.org/r/1470924515-9444-1-git-send-email-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Austin Christ [Thu, 11 Aug 2016 10:42:00 +0000 (11:42 +0100)]
efi/capsule: Allocate whole capsule into virtual memory
According to UEFI 2.6 section 7.5.3, the capsule should be in contiguous
virtual memory and firmware may consume the capsule immediately. To
correctly implement this functionality, the kernel driver needs to vmap
the entire capsule at the time it is made available to firmware.
The virtual allocation of the capsule update has been changed from kmap,
which was only allocating the first page of the update, to vmap, and
allocates the entire data payload.
Signed-off-by: Austin Christ <austinwc@codeaurora.org> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> Reviewed-by: Lee, Chun-Yi <jlee@suse.com> Cc: <stable@vger.kernel.org> # v4.7 Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Bryan O'Donoghue <pure.logic@nexus-software.ie> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kweh Hock Leong <hock.leong.kweh@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1470912120-22831-3-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
Alex Thorlton [Thu, 11 Aug 2016 10:41:59 +0000 (11:41 +0100)]
x86/platform/uv: Skip UV runtime services mapping in the efi_runtime_disabled case
This problem has actually been in the UV code for a while, but we didn't
catch it until recently, because we had been relying on EFI_OLD_MEMMAP
to allow our systems to boot for a period of time. We noticed the issue
when trying to kexec a recent community kernel, where we hit this NULL
pointer dereference in efi_sync_low_kernel_mappings():
[ 0.337515] BUG: unable to handle kernel NULL pointer dereference at 0000000000000880
[ 0.346276] IP: [<ffffffff8105df8d>] efi_sync_low_kernel_mappings+0x5d/0x1b0
The problem doesn't show up with EFI_OLD_MEMMAP because we skip the
chunk of setup_efi_state() that sets the efi_loader_signature for the
kexec'd kernel. When the kexec'd kernel boots, it won't set EFI_BOOT in
setup_arch, so we completely avoid the bug.
We always kexec with noefi on the command line, so this shouldn't be an
issue, but since we're not actually checking for efi_runtime_disabled in
uv_bios_init(), we end up trying to do EFI runtime callbacks when we
shouldn't be. This patch just adds a check for efi_runtime_disabled in
uv_bios_init() so that we don't map in uv_systab when runtime_disabled ==
true.
Signed-off-by: Alex Thorlton <athorlton@sgi.com> Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk> Cc: <stable@vger.kernel.org> # v4.7 Cc: Andy Lutomirski <luto@kernel.org> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Borislav Petkov <bp@suse.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Travis <travis@sgi.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russ Anderson <rja@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/1470912120-22831-2-git-send-email-matt@codeblueprint.co.uk Signed-off-by: Ingo Molnar <mingo@kernel.org>
My EBDA is at 0x2c000, which blocks off everything from 0x2c000 and
up, and my trampoline is 0x6000 bytes (6 pages), so it doesn't fit
in the loader data range at 0x28000.
Without this patch, it panics due to a failure to allocate the
trampoline. With this patch, it works:
[ +0.001744] Base memory trampoline at [ffff880000001000] 1000 size 24576
Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk> 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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mario Limonciello <mario_limonciello@dell.com> Cc: Matt Fleming <mfleming@suse.de> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/998c77b3bf709f3dfed85cb30701ed1a5d8a438b.1470821230.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Wed, 10 Aug 2016 09:29:15 +0000 (02:29 -0700)]
x86/boot: Defer setup_real_mode() to early_initcall time
There's no need to run setup_real_mode() as early as we run it.
Defer it to the same early_initcall that sets up the page
permissions for the real mode code.
This should be a code size reduction. More importantly, it give us
a longer window in which we can allocate the real mode trampoline.
Signed-off-by: Andy Lutomirski <luto@kernel.org> 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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mario Limonciello <mario_limonciello@dell.com> Cc: Matt Fleming <mfleming@suse.de> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/fd62f0da4f79357695e9bf3e365623736b05f119.1470821230.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Wed, 10 Aug 2016 09:29:14 +0000 (02:29 -0700)]
x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly
The initialization process for trampoline_cr4_features and
mmu_cr4_features was confusing. The intent is for mmu_cr4_features
and *trampoline_cr4_features to stay in sync, but
trampoline_cr4_features is NULL until setup_real_mode() runs. The
old code synchronized *trampoline_cr4_features *twice*, once in
setup_real_mode() and once in setup_arch(). It also initialized
mmu_cr4_features in setup_real_mode(), which causes the actual value
of mmu_cr4_features to potentially depend on when setup_real_mode()
is called.
With this patch, mmu_cr4_features is initialized directly in
setup_arch(), and *trampoline_cr4_features is synchronized to
mmu_cr4_features when the trampoline is set up.
After this patch, it should be safe to defer setup_real_mode().
Signed-off-by: Andy Lutomirski <luto@kernel.org> 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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mario Limonciello <mario_limonciello@dell.com> Cc: Matt Fleming <mfleming@suse.de> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/d48a263f9912389b957dd495a7127b009259ffe0.1470821230.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andy Lutomirski [Wed, 10 Aug 2016 09:29:13 +0000 (02:29 -0700)]
x86/boot: Run reserve_bios_regions() after we initialize the memory map
reserve_bios_regions() is a quirk that reserves memory that we might
otherwise think is available. There's no need to run it so early,
and running it before we have the memory map initialized with its
non-quirky inputs makes it hard to make reserve_bios_regions() more
intelligent.
Move it right after we populate the memblock state.
Signed-off-by: Andy Lutomirski <luto@kernel.org> 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: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mario Limonciello <mario_limonciello@dell.com> Cc: Matt Fleming <mfleming@suse.de> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/59f58618911005c799c6c9979ce6ae4881d907c2.1470821230.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Aaron Lu [Thu, 11 Aug 2016 07:44:30 +0000 (15:44 +0800)]
x86/irq: Do not substract irq_tlb_count from irq_call_count
Since commit:
52aec3308db8 ("x86/tlb: replace INVALIDATE_TLB_VECTOR by CALL_FUNCTION_VECTOR")
the TLB remote shootdown is done through call function vector. That
commit didn't take care of irq_tlb_count, which a later commit:
fd0f5869724f ("x86: Distinguish TLB shootdown interrupts from other functions call interrupts")
... tried to fix.
The fix assumes every increase of irq_tlb_count has a corresponding
increase of irq_call_count. So the irq_call_count is always bigger than
irq_tlb_count and we could substract irq_tlb_count from irq_call_count.
Unfortunately this is not true for the smp_call_function_single() case.
The IPI is only sent if the target CPU's call_single_queue is empty when
adding a csd into it in generic_exec_single. That means if two threads
are both adding flush tlb csds to the same CPU's call_single_queue, only
one IPI is sent. In other words, the irq_call_count is incremented by 1
but irq_tlb_count is incremented by 2. Over time, irq_tlb_count will be
bigger than irq_call_count and the substract will produce a very large
irq_call_count value due to overflow.
Considering that:
1) it's not worth to send more IPIs for the sake of accurate counting of
irq_call_count in generic_exec_single();
2) it's not easy to tell if the call function interrupt is for TLB
shootdown in __smp_call_function_single_interrupt().
Not to exclude TLB shootdown from call function count seems to be the
simplest fix and this patch just does that.
This bug was found by LKP's cyclic performance regression tracking recently
with the vm-scalability test suite. I have bisected to commit:
This commit didn't do anything wrong but revealed the irq_call_count
problem. IIUC, the commit makes rwc->remap_one in rmap_walk_file
concurrent with multiple threads. When remap_one is try_to_unmap_one(),
then multiple threads could queue flush TLB to the same CPU but only
one IPI will be sent.
Since the commit was added in Linux v3.19, the counting problem only
shows up from v3.19 onwards.
Signed-off-by: Aaron Lu <aaron.lu@intel.com> Cc: Alex Shi <alex.shi@linaro.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tomoki Sekiyama <tomoki.sekiyama.qu@hitachi.com> Link: http://lkml.kernel.org/r/20160811074430.GA18163@aaronlu.sh.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Dave Hansen [Wed, 10 Aug 2016 17:23:25 +0000 (10:23 -0700)]
x86/mm: Fix swap entry comment and macro
A recent patch changed the format of a swap PTE.
The comment explaining the format of the swap PTE is wrong about
the bits used for the swap type field. Amusingly, the ASCII art
and the patch description are correct, but the comment itself
is wrong.
As I was looking at this, I also noticed that the
SWP_OFFSET_FIRST_BIT has an off-by-one error. This does not
really hurt anything. It just wasted a bit of space in the PTE,
giving us 2^59 bytes of addressable space in our swapfiles
instead of 2^60. But, it doesn't match with the comments, and it
wastes a bit of space, so fix it.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Fixes: 00839ee3b299 ("x86/mm: Move swap offset/type up in PTE to work around erratum") Link: http://lkml.kernel.org/r/20160810172325.E56AD7DA@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
... didn't take steal time into consideration with passing the noirqtime
kernel parameter.
As Paolo pointed out before:
| Why not? If idle=poll, for example, any time the guest is suspended (and
| thus cannot poll) does count as stolen time.
This patch fixes it by reducing steal time from idle time accounting when
the noirqtime parameter is true. The average idle time drops from 56.8%
to 54.75% for nohz idle kvm guest(noirqtime, idle=poll, four vCPUs running
on one pCPU).
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1470893795-3527-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>