Commit Graph

53479 Commits

Author SHA1 Message Date
Suravee Suthikulpanit
bd6fcefc66 iommu/amd: Adding GALOG interrupt handler
This patch adds AMD IOMMU guest virtual APIC log (GALOG) handler.
When IOMMU hardware receives an interrupt targeting a blocking vcpu,
it creates an entry in the GALOG, and generates an interrupt to notify
the AMD IOMMU driver.

At this point, the driver processes the log entry, and notify the SVM
driver via the registered iommu_ga_log_notifier function.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2016-09-05 12:41:46 +02:00
Jan Beulich
d4c4fed08f efi: Make for_each_efi_memory_desc_in_map() cope with running on Xen
While commit 55f1ea1521 ("efi: Fix for_each_efi_memory_desc_in_map()
for empty memmaps") made an attempt to deal with empty memory maps, it
didn't address the case where the map field never gets set, as is
apparently the case when running under Xen.

Reported-by: <lists@ssl-mail.com>
Tested-by: <lists@ssl-mail.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Jan Beulich <jbeulich@suse.com>
[ Guard the loop with a NULL check instead of pointer underflow ]
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-05 11:16:56 +01:00
Ingo Molnar
2cc538412a Merge branch 'perf/urgent' into perf/core, to pick up fixed and resolve conflicts
Conflicts:
	kernel/events/core.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 12:09:59 +02:00
Johannes Berg
d7127b5e5f locking/barriers: Don't use sizeof(void) in lockless_dereference()
My previous commit:

  112dc0c806 ("locking/barriers: Suppress sparse warnings in lockless_dereference()")

caused sparse to complain that (in radix-tree.h) we use sizeof(void)
since that rcu_dereference()s a void *.

Really, all we need is to have the expression *p in here somewhere
to make sure p is a pointer type, and sizeof(*p) was the thing that
came to my mind first to make sure that's done without really doing
anything at runtime.

Another thing I had considered was using typeof(*p), but obviously
we can't just declare a typeof(*p) variable either, since that may
end up being void. Declaring a variable as typeof(*p)* gets around
that, and still checks that typeof(*p) is valid, so do that. This
type construction can't be done for _________p1 because that will
actually be used and causes sparse address space warnings, so keep
a separate unused variable for it.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kbuild-all@01.org
Fixes: 112dc0c806 ("locking/barriers: Suppress sparse warnings in lockless_dereference()")
Link: http://lkml.kernel.org/r/1472192160-4049-1-git-send-email-johannes@sipsolutions.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-05 11:50:42 +02:00
Tony Luck
b8fb03785d locking/static_keys: Provide DECLARE and well as DEFINE macros
We will need to provide declarations of static keys in header
files. Provide DECLARE_STATIC_KEY_{TRUE,FALSE} macros.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/816881cf85bd3cf13385d212882618f38a3b5d33.1472754711.git.tony.luck@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-05 11:47:31 +02:00
Greg Kroah-Hartman
9c2edd8b5b Merge 4.8-rc5 into staging-next
We want the staging fixes in here as well to handle merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-05 08:13:24 +02:00
Greg Kroah-Hartman
b53761e36a Merge 4.8-rc5 into tty-next
We want the fixes in here for merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-05 08:11:21 +02:00
Greg Kroah-Hartman
9b0dd49e35 Merge 4.8-rc5 into usb-testing
We want the USB fixes in here for testing and merge issues.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-05 08:07:58 +02:00
Greg Kroah-Hartman
fbc1ec2efe Merge 4.8-rc5 into char-misc-next
We want the fixes in here for merging and testing.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-05 08:04:07 +02:00
Mahesh Bandewar
24b27fc4cd bonding: Fix bonding crash
Following few steps will crash kernel -

  (a) Create bonding master
      > modprobe bonding miimon=50
  (b) Create macvlan bridge on eth2
      > ip link add link eth2 dev mvl0 address aa:0:0:0:0:01 \
	   type macvlan
  (c) Now try adding eth2 into the bond
      > echo +eth2 > /sys/class/net/bond0/bonding/slaves
      <crash>

Bonding does lots of things before checking if the device enslaved is
busy or not.

In this case when the notifier call-chain sends notifications, the
bond_netdev_event() assumes that the rx_handler /rx_handler_data is
registered while the bond_enslave() hasn't progressed far enough to
register rx_handler for the new slave.

This patch adds a rx_handler check that can be performed right at the
beginning of the enslave code to avoid getting into this situation.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 11:41:12 -07:00
Gregor Boirie
70e483487d iio: add resource managed triggered buffer init helpers
Add resource managed devm_iio_triggered_buffer_setup() and
devm_iio_triggered_buffer_cleanup() to automatically clean up triggered
buffers setup by IIO drivers, thus leading to simplified IIO drivers code.

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-04 15:42:46 +01:00
Gregor Boirie
9083325f11 iio:trigger: add resource managed (un)register
Add resource managed devm_iio_trigger_register() and
devm_iio_triger_unregister() to automatically clean up registered triggers
allocated by IIO drivers, thus leading to simplified IIO drivers code.

Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-04 15:42:37 +01:00
Linus Torvalds
018c81b827 Merge tag 'staging-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging/IIO driver fixes from Greg KH:
 "Here are a number of small fixes for staging and IIO drivers that
  resolve reported problems.

  Full details are in the shortlog.  All of these have been in
  linux-next with no reported issues"

* tag 'staging-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (35 commits)
  arm: dts: rockchip: add reset node for the exist saradc SoCs
  arm64: dts: rockchip: add reset saradc node for rk3368 SoCs
  iio: adc: rockchip_saradc: reset saradc controller before programming it
  iio: accel: kxsd9: Fix raw read return
  iio: adc: ti_am335x_adc: Increase timeout value waiting for ADC sample
  iio: adc: ti_am335x_adc: Protect FIFO1 from concurrent access
  include/linux: fix excess fence.h kernel-doc notation
  staging: wilc1000: correctly check if associatedsta has not been found
  staging: wilc1000: NULL dereference on error
  staging: wilc1000: txq_event: Fix coding error
  MAINTAINERS: Add file patterns for ion device tree bindings
  MAINTAINERS: Update maintainer entry for wilc1000
  iio: chemical: atlas-ph-sensor: fix typo in val assignment
  iio: fix sched WARNING "do not call blocking ops when !TASK_RUNNING"
  staging: comedi: ni_mio_common: fix AO inttrig backwards compatibility
  staging: comedi: dt2811: fix a precedence bug
  staging: comedi: adv_pci1760: Do not return EINVAL for CMDF_ROUND_DOWN.
  staging: comedi: ni_mio_common: fix wrong insn_write handler
  staging: comedi: comedi_test: fix timer race conditions
  staging: comedi: daqboard2000: bug fix board type matching code
  ...
2016-09-03 11:33:33 -07:00
Linus Torvalds
39da979c98 Merge tag 'tty-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull serial driver fixes from Greg KH:
 "Here are some small serial driver fixes for 4.8-rc5.  One fixes an
  oft-reported build issue with the fintek driver, another reverts a
  patch that was causing problems, one fixes a crash, and some new
  device ids were added.

  All of these have been in linux-next for a while"

* tag 'tty-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250: added acces i/o products quad and octal serial cards
  serial: 8250_mid: fix divide error bug if baud rate is 0
  Revert "tty/serial/8250: use mctrl_gpio helpers"
  8250/fintek: rename IRQ_MODE macro
2016-09-03 11:29:31 -07:00
Linus Torvalds
70dad4998e Merge tag 'usb-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/PHY fixes from Greg KH:
 "Here are some USB and PHY driver fixes for 4.8-rc5

  Nothing major, lots of little fixes for reported bugs, and a build fix
  for a missing .h file that the phy drivers needed.  All of these have
  been in linux-next for a while with no reported issues"

* tag 'usb-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (24 commits)
  usb: musb: Fix locking errors for host only mode
  usb: dwc3: gadget: always decrement by 1
  usb: dwc3: debug: fix ep name on trace output
  usb: gadget: udc: core: don't starve DMA resources
  USB: serial: option: add WeTelecom 0x6802 and 0x6803 products
  USB: avoid left shift by -1
  USB: fix typo in wMaxPacketSize validation
  usb: gadget: Add the gserial port checking in gs_start_tx()
  usb: dwc3: gadget: don't rely on jiffies while holding spinlock
  usb: gadget: fsl_qe_udc: signedness bug in qe_get_frame()
  usb: gadget: function: f_rndis: socket buffer may be NULL
  usb: gadget: function: f_eem: socket buffer may be NULL
  usb: renesas_usbhs: gadget: fix return value check in usbhs_mod_gadget_probe()
  usb: dwc2: Add reset control to dwc2
  usb: dwc3: core: allow device to runtime_suspend several times
  usb: dwc3: pci: runtime_resume child device
  USB: serial: option: add WeTelecom WM-D200
  usb: chipidea: udc: don't touch DP when controller is in host mode
  USB: serial: mos7840: fix non-atomic allocation in write path
  USB: serial: mos7720: fix non-atomic allocation in write path
  ...
2016-09-03 11:24:23 -07:00
Matt Ranostay
c8cdf70890 iio: trigger: allow immutable triggers to be assigned
There are times when an assigned trigger to a device shouldn't ever
change after intialization.

Examples of this being used is when an provider device has a trigger
that is assigned to an ADC, which uses it populate data into a callback
buffer.

Signed-off-by: Matt Ranostay <matt@ranostay.consulting>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
2016-09-03 15:31:55 +01:00
Rafał Miłecki
3f37ec79dd bcma: support BCM53573 series of wireless SoCs
BCM53573 seems to be the first series of Northstar family with wireless
on the chip. The base models are BCM53573-s (A0, A1) and there is also
BCM47189B0 which seems to be some small modification.

The only problem with these chipsets seems to be watchdog. It's totally
unavailable on 53573A0 / 53573A1 and preferable PMU watchdog is broken
on 53573B0 / 53573B1.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2016-09-03 12:58:42 +03:00
Linus Torvalds
0141af184a Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A collection of fixes for the nvme over fabrics code"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme-rdma: Get rid of redundant defines
  nvme-rdma: Get rid of duplicate variable
  nvme: fabrics drivers don't need the nvme-pci driver
  nvme-fabrics: get a reference when reusing a nvme_host structure
  nvme-fabrics: change NQN UUID to big-endian format
  nvme-loop: set sqsize to 0-based value, per spec
  nvme-rdma: fix sqsize/hsqsize per spec
  fabrics: define admin sqsize min default, per spec
  nvmet-rdma: +1 to *queue_size from hsqsize/hrqsize
  nvmet-rdma: Fix use after free
  nvme-rdma: initialize ret to zero to avoid returning garbage
2016-09-02 21:05:38 -07:00
Linus Torvalds
601b586994 Merge tag 'acpi-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI fixes ffrom Rafael Wysocki:
 "Two stable-candidate fixes for the ACPI early device probing code
  added during the 4.4 cycle, one fixing a typo in a stub macro used
  when CONFIG_ACPI is unset and one that prevents sleeping functions
  from being called under a spinlock (Lorenzo Pieralisi)"

* tag 'acpi-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / drivers: replace acpi_probe_lock spinlock with mutex
  ACPI / drivers: fix typo in ACPI_DECLARE_PROBE_ENTRY macro
2016-09-02 15:16:04 -07:00
Lorenzo Pieralisi
3feab13c91 ACPI / drivers: fix typo in ACPI_DECLARE_PROBE_ENTRY macro
When the ACPI_DECLARE_PROBE_ENTRY macro was added in
commit e647b53227 ("ACPI: Add early device probing infrastructure"),
a stub macro adding an unused entry was added for the !CONFIG_ACPI
Kconfig option case to make sure kernel code making use of the
macro did not require to be guarded within CONFIG_ACPI in order to
be compiled.

The stub macro was never used since all kernel code that defines
ACPI_DECLARE_PROBE_ENTRY entries is currently guarded within
CONFIG_ACPI; it contains a typo that should be nonetheless fixed.

Fix the typo in the stub (ie !CONFIG_ACPI) ACPI_DECLARE_PROBE_ENTRY()
macro so that it can actually be used if needed.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Fixes: e647b53227 (ACPI: Add early device probing infrastructure)
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-02 22:21:34 +02:00
Sebastian Frias
f88eecfe2f genirq/generic_chip: Verify irqs_per_chip <= 32
Most (if not all) code here implicitly assumes that the maximum number of
IRQs per chip will be 32, and thus uses 'u32' or 'unsigned long' for many
tasks (for example "struct irq_data" declares its 'mask' field as 'u32',
and "struct irq_chip_generic" declares its 'installed' field as 'unsigned
long')

However, there is no check to verify that irqs_per_chip is <= 32.  Hence,
calling irq_alloc_domain_generic_chips() with a bigger value will result in
unexpected results.

Provide a wrapper with a MAYBE_BUILD_BUG_ON(nrirqs >= 32) to catch such
cases.

[ tglx: Reduced changelog to the essential information ]

Signed-off-by: Sebastian Frias <sf84@laposte.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mason <slash.tmp@free.fr>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/57B31D94.5040701@laposte.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-02 20:20:59 +02:00
Sebastian Andrzej Siewior
8017c27919 net/virtio-net: Convert to hotplug state machine
Install the callbacks via the state machine.

The driver supports multiple instances and therefore the new
cpuhp_state_add_instance_nocalls() infrastrucure is used. The driver
currently uses get_online_cpus() to avoid missing a CPU hotplug event while
invoking virtnet_set_affinity(). This could be avoided by using
cpuhp_state_add_instance() variant which holds the hotplug lock and invokes
callback during registration. This is more or less a 1:1 conversion of the
current code.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: netdev@vger.kernel.org
Cc: Will Deacon <will.deacon@arm.com>
Cc: virtualization@lists.linux-foundation.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/1471024183-12666-7-git-send-email-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-02 20:05:06 +02:00
Sebastian Andrzej Siewior
6e103c0cfe arm/perf: Use multi instance instead of custom list
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160817171420.sdwk2qivxunzryz4@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-02 20:05:06 +02:00
Thomas Gleixner
cf392d10b6 cpu/hotplug: Add multi instance support
This patch adds the ability for a given state to have multiple
instances. Until now all states have a single instance and the startup /
teardown callback use global variables.
A few drivers need to perform a the same callbacks on multiple
"instances". Currently we have three drivers in tree which all have a
global list which they iterate over. With multi instance they support
don't need their private list and the functionality has been moved into
core code. Plus we hold the hotplug lock in core so no cpus comes/goes
while instances are registered and we do rollback in error case :)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/1471024183-12666-3-git-send-email-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-02 20:05:05 +02:00
Alexei Starovoitov
aa6a5f3cb2 perf, bpf: add perf events core support for BPF_PROG_TYPE_PERF_EVENT programs
Allow attaching BPF_PROG_TYPE_PERF_EVENT programs to sw and hw perf events
via overflow_handler mechanism.
When program is attached the overflow_handlers become stacked.
The program acts as a filter.
Returning zero from the program means that the normal perf_event_output handler
will not be called and sampling event won't be stored in the ring buffer.

The overflow_handler_context==NULL is an additional safety check
to make sure programs are not attached to hw breakpoints and watchdog
in case other checks (that prevent that now anyway) get accidentally
relaxed in the future.

The program refcnt is incremented in case perf_events are inhereted
when target task is forked.
Similar to kprobe and tracepoint programs there is no ioctl to
detach the program or swap already attached program. The user space
expected to close(perf_event_fd) like it does right now for kprobe+bpf.
That restriction simplifies the code quite a bit.

The invocation of overflow_handler in __perf_event_overflow() is now
done via READ_ONCE, since that pointer can be replaced when the program
is attached while perf_event itself could have been active already.
There is no need to do similar treatment for event->prog, since it's
assigned only once before it's accessed.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02 10:46:44 -07:00
Alexei Starovoitov
0515e5999a bpf: introduce BPF_PROG_TYPE_PERF_EVENT program type
Introduce BPF_PROG_TYPE_PERF_EVENT programs that can be attached to
HW and SW perf events (PERF_TYPE_HARDWARE and PERF_TYPE_SOFTWARE
correspondingly in uapi/linux/perf_event.h)

The program visible context meta structure is
struct bpf_perf_event_data {
    struct pt_regs regs;
     __u64 sample_period;
};
which is accessible directly from the program:
int bpf_prog(struct bpf_perf_event_data *ctx)
{
  ... ctx->sample_period ...
  ... ctx->regs.ip ...
}

The bpf verifier rewrites the accesses into kernel internal
struct bpf_perf_event_data_kern which allows changing
struct perf_sample_data without affecting bpf programs.
New fields can be added to the end of struct bpf_perf_event_data
in the future.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-02 10:46:44 -07:00
Steven Rostedt (Red Hat)
7b2c862501 tracing: Add NMI tracing in hwlat detector
As NMIs can also cause latency when interrupts are disabled, the hwlat
detectory has no way to know if the latency it detects is from an NMI or an
SMI or some other hardware glitch.

As ftrace_nmi_enter/exit() funtions are no longer used (except for sh, which
isn't supported anymore), I converted those to "arch_ftrace_nmi_enter/exit"
and use ftrace_nmi_enter/exit() to check if hwlat detector is tracing or
not, and if so, it calls into the hwlat utility.

Since the hwlat detector only has a single kthread that is spinning with
interrupts disabled, it marks what CPU it is on, and if the NMI callback
happens on that CPU, it records the time spent in that NMI. This is added to
the output that is generated by the hwlat detector as:

 #3     inner/outer(us):    9/9     ts:1470836488.206734548
 #4     inner/outer(us):    0/8     ts:1470836497.140808588
 #5     inner/outer(us):    0/6     ts:1470836499.140825168 nmi-total:5 nmi-count:1
 #6     inner/outer(us):    9/9     ts:1470836501.140841748

All time is still tracked in microseconds.

The NMI information is only shown when an NMI occurred during the sample.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-02 12:47:55 -04:00
Linus Torvalds
f28929ba36 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "Most of this is regression fixes for posix acl behavior introduced in
  4.8-rc1 (these were caught by the pjd-fstest suite).  The are also
  miscellaneous fixes marked as stable material and cleanups.

  Other than overlayfs code, it touches <linux/fs.h> to add a constant
  with which to disable posix acl caching.  No changes needed to the
  actual caching code, it automatically does the right thing, although
  later we may want to optimize this case.

  I'm now testing overlayfs with the following test suites to catch
  regressions:

   - unionmount-testsuite
   - xfstests
   - pjd-fstest"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: update doc
  ovl: listxattr: use strnlen()
  ovl: Switch to generic_getxattr
  ovl: copyattr after setting POSIX ACL
  ovl: Switch to generic_removexattr
  ovl: Get rid of ovl_xattr_noacl_handlers array
  ovl: Fix OVL_XATTR_PREFIX
  ovl: fix spelling mistake: "directries" -> "directories"
  ovl: don't cache acl on overlay layer
  ovl: use cached acl on underlying layer
  ovl: proper cleanup of workdir
  ovl: remove posix_acl_default from workdir
  ovl: handle umask and posix_acl_default correctly on creation
  ovl: don't copy up opaqueness
2016-09-02 09:32:15 -07:00
Arnd Bergmann
2b97f10b38 Merge tag 'gpmc-omap-for-v4.9' of https://github.com/rogerq/linux into next/drivers
Merge "OMAP-GPMC: driver updates for v4.9" from Roger Quadros:

* Fix potential build failure if CONFIG_OMAP_GPMC is disabled while
  OMAP_NAND driver is enabled
* Trivial fixes which fix build warnings and code check tool warnings
  (Coccinelle)
* Use devm_gpiochip_add_data()

* tag 'gpmc-omap-for-v4.9' of https://github.com/rogerq/linux:
  memory: omap-gpmc: make gpmc_clk_ticks_to_ns() static
  memory: omap-gpmc: Fix build with CONFIG_OMAP_GPMC disabled
  memory: omap-gpmc: use devm_gpiochip_add_data()
  memory: omap-gpmc: Delete an unnecessary check before the function call "gpiochip_free_own_desc"
2016-09-02 18:27:11 +02:00
K. Y. Srinivasan
509879bdb3 Drivers: hv: Introduce a policy for controlling channel affinity
Introduce a mechanism to control how channels will be affinitized. We will
support two policies:

1. HV_BALANCED: All performance critical channels will be dstributed
evenly amongst all the available NUMA nodes. Once the Node is assigned,
we will assign the CPU based on a simple round robin scheme.

2. HV_LOCALIZED: Only the primary channels are distributed across all
NUMA nodes. Sub-channels will be in the same NUMA node as the primary
channel. This is the current behaviour.

The default policy will be the HV_BALANCED as it can minimize the remote
memory access on NUMA machines with applications that span NUMA nodes.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02 17:22:51 +02:00
Vitaly Kuznetsov
bb08d431a9 Drivers: hv: ring_buffer: count on wrap around mappings in get_next_pkt_raw()
With wrap around mappings in place we can always provide drivers with
direct links to packets on the ring buffer, even when they wrap around.
Do the required updates to get_next_pkt_raw()/put_pkt_raw()

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Tested-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02 17:22:51 +02:00
Andy Shevchenko
d2f5a7311b dmaengine: hsu: refactor hsu_dma_do_irq() to return int
Since we have nice macro IRQ_RETVAL() we would use it to convert a flag of
handled interrupt from int to irqreturn_t.

The rationale of doing this is:
a) hence we implicitly mark hsu_dma_do_irq() as an auxiliary function that
   can't be used as interrupt handler directly, and
b) to be in align with serial driver which is using serial8250_handle_irq()
   that returns plain int by design.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02 15:05:48 +02:00
Alexander Sverdlin
46e36683f4 serial: earlycon: Extend earlycon command line option to support 64-bit addresses
earlycon implementation used "unsigned long" internally, but there are systems
(ARM with LPAE) where sizeof(unsigned long) == 4 and uart is mapped beyond 4GiB
address range.

Switch to resource_size_t internally and replace obsoleted simple_strtoul() with
kstrtoull().

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02 15:03:35 +02:00
Nikolay Aleksandrov
b6cb5ac833 net: bridge: add per-port multicast flood flag
Add a per-port flag to control the unknown multicast flood, similar to the
unknown unicast flood flag and break a few long lines in the netlink flag
exports.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 22:48:33 -07:00
Linus Torvalds
b9677faf45 Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "14 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  rapidio/tsi721: fix incorrect detection of address translation condition
  rapidio/documentation/mport_cdev: add missing parameter description
  kernel/fork: fix CLONE_CHILD_CLEARTID regression in nscd
  MAINTAINERS: Vladimir has moved
  mm, mempolicy: task->mempolicy must be NULL before dropping final reference
  printk/nmi: avoid direct printk()-s from __printk_nmi_flush()
  treewide: remove references to the now unnecessary DEFINE_PCI_DEVICE_TABLE
  drivers/scsi/wd719x.c: remove last declaration using DEFINE_PCI_DEVICE_TABLE
  mm, vmscan: only allocate and reclaim from zones with pages managed by the buddy allocator
  lib/test_hash.c: fix warning in preprocessor symbol evaluation
  lib/test_hash.c: fix warning in two-dimensional array init
  kconfig: tinyconfig: provide whole choice blocks to avoid warnings
  kexec: fix double-free when failing to relocate the purgatory
  mm, oom: prevent premature OOM killer invocation for high order request
2016-09-01 18:23:22 -07:00
David Rientjes
c11600e4fe mm, mempolicy: task->mempolicy must be NULL before dropping final reference
KASAN allocates memory from the page allocator as part of
kmem_cache_free(), and that can reference current->mempolicy through any
number of allocation functions.  It needs to be NULL'd out before the
final reference is dropped to prevent a use-after-free bug:

	BUG: KASAN: use-after-free in alloc_pages_current+0x363/0x370 at addr ffff88010b48102c
	CPU: 0 PID: 15425 Comm: trinity-c2 Not tainted 4.8.0-rc2+ #140
	...
	Call Trace:
		dump_stack
		kasan_object_err
		kasan_report_error
		__asan_report_load2_noabort
		alloc_pages_current	<-- use after free
		depot_save_stack
		save_stack
		kasan_slab_free
		kmem_cache_free
		__mpol_put		<-- free
		do_exit

This patch sets current->mempolicy to NULL before dropping the final
reference.

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1608301442180.63329@chino.kir.corp.google.com
Fixes: cd11016e5f ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB")
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>	[4.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-01 17:52:01 -07:00
Joe Perches
7e93215990 treewide: remove references to the now unnecessary DEFINE_PCI_DEVICE_TABLE
It's been eliminated from the sources, remove it from everywhere else.

Link: http://lkml.kernel.org/r/076eff466fd7edb550c25c8b25d76924ca0eba62.1472660229.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-01 17:52:01 -07:00
Mel Gorman
6aa303defb mm, vmscan: only allocate and reclaim from zones with pages managed by the buddy allocator
Firmware Assisted Dump (FA_DUMP) on ppc64 reserves substantial amounts
of memory when booting a secondary kernel.  Srikar Dronamraju reported
that multiple nodes may have no memory managed by the buddy allocator
but still return true for populated_zone().

Commit 1d82de618d ("mm, vmscan: make kswapd reclaim in terms of
nodes") was reported to cause kswapd to spin at 100% CPU usage when
fadump was enabled.  The old code happened to deal with the situation of
a populated node with zero free pages by co-incidence but the current
code tries to reclaim populated zones without realising that is
impossible.

We cannot just convert populated_zone() as many existing users really
need to check for present_pages.  This patch introduces a managed_zone()
helper and uses it in the few cases where it is critical that the check
is made for managed pages -- zonelist construction and page reclaim.

Link: http://lkml.kernel.org/r/20160831195104.GB8119@techsingularity.net
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-01 17:52:01 -07:00
Roopa Prabhu
d297653dd6 rtnetlink: fdb dump: optimize by saving last interface markers
fdb dumps spanning multiple skb's currently restart from the first
interface again for every skb. This results in unnecessary
iterations on the already visited interfaces and their fdb
entries. In large scale setups, we have seen this to slow
down fdb dumps considerably. On a system with 30k macs we
see fdb dumps spanning across more than 300 skbs.

To fix the problem, this patch replaces the existing single fdb
marker with three markers: netdev hash entries, netdevs and fdb
index to continue where we left off instead of restarting from the
first netdev. This is consistent with link dumps.

In the process of fixing the performance issue, this patch also
re-implements fix done by
commit 472681d57a ("net: ndo_fdb_dump should report -EMSGSIZE to rtnl_fdb_dump")
(with an internal fix from Wilson Kok) in the following ways:
- change ndo_fdb_dump handlers to return error code instead
of the last fdb index
- use cb->args strictly for dump frag markers and not error codes.
This is consistent with other dump functions.

Below results were taken on a system with 1000 netdevs
and 35085 fdb entries:
before patch:
$time bridge fdb show | wc -l
15065

real    1m11.791s
user    0m0.070s
sys 1m8.395s

(existing code does not return all macs)

after patch:
$time bridge fdb show | wc -l
35085

real    0m2.017s
user    0m0.113s
sys 0m1.942s

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 16:56:15 -07:00
Linus Torvalds
511a8cdb65 Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
Pull audit fixes from Paul Moore:
 "Two small patches to fix some bugs with the audit-by-executable
  functionality we introduced back in v4.3 (both patches are marked
  for the stable folks)"

* 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit:
  audit: fix exe_file access in audit_exe_compare
  mm: introduce get_task_exe_file
2016-09-01 15:55:56 -07:00
Linus Torvalds
7d1ce606a3 Merge tag 'xfs-iomap-for-linus-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs and iomap fixes from Dave Chinner:
 "Most of these changes are small regression fixes that address problems
  introduced in the 4.8-rc1 window.  The two fixes that aren't (IO
  completion fix and superblock inprogress check) are fixes for problems
  introduced some time ago and need to be pushed back to stable kernels.

  Changes in this update:
   - iomap FIEMAP_EXTENT_MERGED usage fix
   - additional mount-time feature restrictions
   - rmap btree query fixes
   - freeze/unmount io completion workqueue fix
   - memory corruption fix for deferred operations handling"

* tag 'xfs-iomap-for-linus-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: track log done items directly in the deferred pending work item
  iomap: don't set FIEMAP_EXTENT_MERGED for extent based filesystems
  xfs: prevent dropping ioend completions during buftarg wait
  xfs: fix superblock inprogress check
  xfs: simple btree query range should look right if LE lookup fails
  xfs: fix some key handling problems in _btree_simple_query_range
  xfs: don't log the entire end of the AGF
  xfs: disallow mounting of realtime + rmap filesystems
  xfs: don't perform lookups on zero-height btrees
2016-09-01 15:33:16 -07:00
Carlo Caione
2c4ddb2155 firmware: Amlogic: Add secure monitor driver
Introduce a driver to provide calls into secure monitor mode.

In the Amlogic SoCs these calls are used for multiple reasons: access to
NVMEM, set USB boot, enable JTAG, etc...

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Carlo Caione <carlo@endlessm.com>
[khilman: add in SZ_4K cleanup]
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
2016-09-01 14:23:39 -07:00
Namhyung Kim
8861dd303c ftrace: Access ret_stack->subtime only in the function profiler
The subtime is used only for function profiler with function graph
tracer enabled.  Move the definition of subtime under
CONFIG_FUNCTION_PROFILER to reduce the memory usage.  Also move the
initialization of subtime into the graph entry callback.

Link: http://lkml.kernel.org/r/20160831025529.24018-1-namhyung@kernel.org

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-09-01 12:19:40 -04:00
Martin Schwidefsky
f5b55fa1f8 RAID/s390: provide raid6 recovery optimization
The XC instruction can be used to improve the speed of the raid6
recovery. The loops now operate on blocks of 256 bytes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-01 16:13:25 +02:00
Phil Reid
3b5dd3a494 power: supply: sbs-battery: Use gpio_desc and sleeping calls for battery detect
Switch to using new gpio_desc interface and devm gpio get calls to
automatically manage gpio resource. Use gpiod_get_value which handles
active high / low calls.

If gpio_detect is set then force loading of the driver as it is
reasonable to assume that the battery may not be present.

Update the is_present flag immediately in the IRQ.

Remove legacy gpio specification from platform data.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Sebastian Reichel <sre@kernel.org>
2016-09-01 16:06:14 +02:00
Will Deacon
e937dd5782 arm64: debug: convert OS lock CPU hotplug notifier to new infrastructure
The arm64 debug monitor initialisation code uses a CPU hotplug notifier
to clear the OS lock when CPUs come online.

This patch converts the code to the new hotplug mechanism.

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-01 13:45:58 +01:00
Will Deacon
d7a83d127a arm64: hw_breakpoint: convert CPU hotplug notifier to new infrastructure
The arm64 hw_breakpoint implementation uses a CPU hotplug notifier to
reset the {break,watch}point registers when CPUs come online.

This patch converts the code to the new hotplug mechanism, whilst moving
the invocation earlier to remove the need to disable IRQs explicitly in
the driver (which could cause havok if we trip a watchpoint in an IRQ
handler whilst restoring the debug register state).

Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-01 13:45:51 +01:00
Miklos Szeredi
2a3a2a3f35 ovl: don't cache acl on overlay layer
Some operations (setxattr/chmod) can make the cached acl stale.  We either
need to clear overlay's acl cache for the affected inode or prevent acl
caching on the overlay altogether.  Preventing caching has the following
advantages:

 - no double caching, less memory used

 - overlay cache doesn't go stale when fs clears it's own cache

Possible disadvantage is performance loss.  If that becomes a problem
get_acl() can be optimized for overlayfs.

This patch disables caching by pre setting i_*acl to a value that

  - has bit 0 set, so is_uncached_acl() will return true

  - is not equal to ACL_NOT_CACHED, so get_acl() will not overwrite it

The constant -3 was chosen for this purpose.

Fixes: 39a25b2b37 ("ovl: define ->get_acl() for overlay inodes")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Vegard Nossum
979515c564 time: Avoid undefined behaviour in ktime_add_safe()
I ran into this:

    ================================================================================
    UBSAN: Undefined behaviour in kernel/time/hrtimer.c:310:16
    signed integer overflow:
    9223372036854775807 + 50000 cannot be represented in type 'long long int'
    CPU: 2 PID: 4798 Comm: trinity-c2 Not tainted 4.8.0-rc1+ #91
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
     0000000000000000 ffff88010ce6fb88 ffffffff82344740 0000000041b58ab3
     ffffffff84f97a20 ffffffff82344694 ffff88010ce6fbb0 ffff88010ce6fb60
     000000000000c350 ffff88010ce6f968 dffffc0000000000 ffffffff857bc320
    Call Trace:
     [<ffffffff82344740>] dump_stack+0xac/0xfc
     [<ffffffff82344694>] ? _atomic_dec_and_lock+0xc4/0xc4
     [<ffffffff8242df78>] ubsan_epilogue+0xd/0x8a
     [<ffffffff8242e6b4>] handle_overflow+0x202/0x23d
     [<ffffffff8242e4b2>] ? val_to_string.constprop.6+0x11e/0x11e
     [<ffffffff8236df71>] ? timerqueue_add+0x151/0x410
     [<ffffffff81485c48>] ? hrtimer_start_range_ns+0x3b8/0x1380
     [<ffffffff81795631>] ? memset+0x31/0x40
     [<ffffffff8242e6fd>] __ubsan_handle_add_overflow+0xe/0x10
     [<ffffffff81488ac9>] hrtimer_nanosleep+0x5d9/0x790
     [<ffffffff814884f0>] ? hrtimer_init_sleeper+0x80/0x80
     [<ffffffff813a9ffb>] ? __might_sleep+0x5b/0x260
     [<ffffffff8148be10>] common_nsleep+0x20/0x30
     [<ffffffff814906c7>] SyS_clock_nanosleep+0x197/0x210
     [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150
     [<ffffffff823c7113>] ? __this_cpu_preempt_check+0x13/0x20
     [<ffffffff8162ef60>] ? __context_tracking_exit.part.3+0x30/0x1b0
     [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150
     [<ffffffff81007bd3>] do_syscall_64+0x1b3/0x4b0
     [<ffffffff845f85aa>] entry_SYSCALL64_slow_path+0x25/0x25
    ================================================================================

Add a new ktime_add_unsafe() helper which doesn't check for overflow, but
doesn't throw a UBSAN warning when it does overflow either.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2016-08-31 14:43:36 -07:00
Vegard Nossum
469e857f37 time: Avoid undefined behaviour in timespec64_add_safe()
I ran into this:

    ================================================================================
    UBSAN: Undefined behaviour in kernel/time/time.c:783:2
    signed integer overflow:
    5273 + 9223372036854771711 cannot be represented in type 'long int'
    CPU: 0 PID: 17363 Comm: trinity-c0 Not tainted 4.8.0-rc1+ #88
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org
    04/01/2014
     0000000000000000 ffff88011457f8f0 ffffffff82344f50 0000000041b58ab3
     ffffffff84f98080 ffffffff82344ea4 ffff88011457f918 ffff88011457f8c8
     ffff88011457f8e0 7fffffffffffefff ffff88011457f6d8 dffffc0000000000
    Call Trace:
     [<ffffffff82344f50>] dump_stack+0xac/0xfc
     [<ffffffff82344ea4>] ? _atomic_dec_and_lock+0xc4/0xc4
     [<ffffffff8242f4c8>] ubsan_epilogue+0xd/0x8a
     [<ffffffff8242fc04>] handle_overflow+0x202/0x23d
     [<ffffffff8242fa02>] ? val_to_string.constprop.6+0x11e/0x11e
     [<ffffffff823c7837>] ? debug_smp_processor_id+0x17/0x20
     [<ffffffff8131b581>] ? __sigqueue_free.part.13+0x51/0x70
     [<ffffffff8146d4e0>] ? rcu_is_watching+0x110/0x110
     [<ffffffff8242fc4d>] __ubsan_handle_add_overflow+0xe/0x10
     [<ffffffff81476ef8>] timespec64_add_safe+0x298/0x340
     [<ffffffff81476c60>] ? timespec_add_safe+0x330/0x330
     [<ffffffff812f7990>] ? wait_noreap_copyout+0x1d0/0x1d0
     [<ffffffff8184bf18>] poll_select_set_timeout+0xf8/0x170
     [<ffffffff8184be20>] ? poll_schedule_timeout+0x2b0/0x2b0
     [<ffffffff813aa9bb>] ? __might_sleep+0x5b/0x260
     [<ffffffff833c8a87>] __sys_recvmmsg+0x107/0x790
     [<ffffffff833c8980>] ? SyS_recvmsg+0x20/0x20
     [<ffffffff81486378>] ? hrtimer_start_range_ns+0x3b8/0x1380
     [<ffffffff845f8bfb>] ? _raw_spin_unlock_irqrestore+0x3b/0x60
     [<ffffffff8148bcea>] ? do_setitimer+0x39a/0x8e0
     [<ffffffff813aa9bb>] ? __might_sleep+0x5b/0x260
     [<ffffffff833c9110>] ? __sys_recvmmsg+0x790/0x790
     [<ffffffff833c91e9>] SyS_recvmmsg+0xd9/0x160
     [<ffffffff833c9110>] ? __sys_recvmmsg+0x790/0x790
     [<ffffffff823c7853>] ? __this_cpu_preempt_check+0x13/0x20
     [<ffffffff8162f680>] ? __context_tracking_exit.part.3+0x30/0x1b0
     [<ffffffff833c9110>] ? __sys_recvmmsg+0x790/0x790
     [<ffffffff81007bd3>] do_syscall_64+0x1b3/0x4b0
     [<ffffffff845f936a>] entry_SYSCALL64_slow_path+0x25/0x25
    ================================================================================

Line 783 is this:

783         set_normalized_timespec64(&res, lhs.tv_sec + rhs.tv_sec,
784                         lhs.tv_nsec + rhs.tv_nsec);

In other words, since lhs.tv_sec and rhs.tv_sec are both time64_t, this
is a signed addition which will cause undefined behaviour on overflow.

Note that this is not currently a huge concern since the kernel should be
built with -fno-strict-overflow by default, but could be a problem in the
future, a problem with older compilers, or other compilers than gcc.

The easiest way to avoid the overflow is to cast one of the arguments to
unsigned (so the addition will be done using unsigned arithmetic).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2016-08-31 14:43:35 -07:00