Now we populate each directory with a read/write (mode 0644) file
named "cpus". This is used to over-ride the resources available
to processes in the default resource group when running on specific
CPUs.  Each "cpus" file reads as a cpumask showing which CPUs belong
to this resource group. Initially all online CPUs are assigned to
the default group. They can be added to other groups by writing a
cpumask to the "cpus" file in the directory for the resource group
(which will remove them from the previous group to which they were
assigned). CPU online/offline operations will delete CPUs that go
offline from whatever group they are in and add new CPUs to the
default group.

If there are CPUs assigned to a group when the directory is removed,
they are returned to the default group.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477692289-37412-7-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Resource control groups are represented as directories in the resctrl
file system. The root directory describes the default resources available
to tasks that have not been assigned specific resources. Other directories
can be created at the root level to make new resource groups. It is not
permitted to make directories within other directories.

Hardware uses a CLOSID (Class of service ID) to determine which resource
limits are currently in effect. The exact number available is enumerated
by CPUID leaf 0x10, but on current implementations it is a small number.
We implement a simple bitmask allocator for CLOSIDs.

Each resource control group uses one CLOSID, which limits the total number
of directories that can be created.

Resource groups can be removed using rmdir.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477692289-37412-6-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

For the convenience of applications we make the decoded values of some
of the CPUID values available in read-only (0444) files.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477692289-37412-5-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Use kernfs as basis for our user interface filesystem. This patch
supports mount/umount, and one mount parameter "cdp" to enable code/data
prioritization (though all we do at this point is ensure that the system
can support CDP).  The file system is not populated yet in this patch.

[ tglx: Fixed up a few nits and added cdp handling in case of error ]
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477692289-37412-4-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

We use the cpu hotplug notifier to catch each cpu in turn and look at
its cache topology w.r.t each of the resource groups. As we discover
new resources, we initialize the bitmask array for each to the default
(full access) value.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477692289-37412-3-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

The documentation describes user interface of how to allocate resource
in Intel RDT.

Please note that the documentation covers generic user interface. Current
patch set code only implemente CAT L3. CAT L2 code will be sent later.

[ tglx: Added cpu example ]
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477692289-37412-2-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

PQR_ASSOC MSR contains the RMID used for preformance monitoring of cache
occupancy and memory bandwidth. The upper 32bit of this MSR contain the
CLOSID for cache allocation. So we need to share the information between
the two facilities.

Move the rdt data structure declaration into the shared header file and
make the per cpu data structure containing the MSR values global.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-10-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Define struct rdt_resource to hold all the parameterized values for an RDT
resource and fill in the CPUID enumerated values from leaf 0x10 if
available. Hard code them for the MSR detected Haswells.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-9-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Some Haswell generation CPUs support RDT, but they don't enumerate this via
CPUID.  Use rdmsr_safe() and wrmsr_safe() to probe the MSRs on cpu model 63
(INTEL_FAM6_HASWELL_X)

Move the relevant defines into a common header file which is shared between
RDT/CQM and RDT/Allocation to avoid duplication.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-8-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Introduce CONFIG_INTEL_RDT_A (default: no, dependent on CPU_SUP_INTEL) to
control inclusion of Resource Director Technology in the build.

Simple init() routine just checks which features are present. If they are
pr_info() one line summary for each feature for now.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-7-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Check CPUID leaves for all the Resource Director Technology (RDT)
Cache Allocation Technology (CAT) bits.

Presence of allocation features:
  CPUID.(EAX=7H, ECX=0):EBX[bit 15]	X86_FEATURE_RDT_A

L2 and L3 caches are each separately enabled:
  CPUID.(EAX=10H, ECX=0):EBX[bit 1]	X86_FEATURE_CAT_L3
  CPUID.(EAX=10H, ECX=0):EBX[bit 2]	X86_FEATURE_CAT_L2

L3 cache may support independent control of allocation for
code and data (CDP = Code/Data Prioritization):
  CPUID.(EAX=10H, ECX=1):ECX[bit 2]	X86_FEATURE_CDP_L3

[ tglx: Fixed up Borislavs comments and moved the feature bits into a gap ]
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Acked-by: N"Borislav Petkov" <bp@suse.de>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-5-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Cache id is retrieved from APIC ID and CPUID leaf 4 on x86.

For more details please see the section on "Cache ID Extraction
Parameters" in "Intel 64 Architecture Processor Topology Enumeration".

Also the documentation of the CPUID instruction in the "Intel 64 and
IA-32 Architectures Software Developer's Manual"
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-4-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Cache management software needs an id for each instance of a cache of
a particular type.

The current cacheinfo structure does not provide any information about
the underlying hardware so there is no way to expose it.

Hardware with cache management features provides means (cpuid, enumeration
etc.) to retrieve the hardware id of a particular cache instance. Cache
instances which share hardware have the same hardware id.

Add an 'id' field to struct cacheinfo to store this information. Expose
this information under the /sys/devices/system/cpu/cpu*/cache/index*/
directory as well.
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "Tony Luck" <tony.luck@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-3-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Add an ABI document entry for /sys/devices/system/cpu/cpu*/cache/index*/id.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NFenghua Yu <fenghua.yu@intel.com>
Cc: "Ravi V Shankar" <ravi.v.shankar@intel.com>
Cc: "David Carrillo-Cisneros" <davidcc@google.com>
Cc: "Sai Prakhya" <sai.praneeth.prakhya@intel.com>
Cc: "Peter Zijlstra" <peterz@infradead.org>
Cc: "Stephane Eranian" <eranian@google.com>
Cc: "Dave Hansen" <dave.hansen@intel.com>
Cc: "Shaohua Li" <shli@fb.com>
Cc: "Nilay Vaish" <nilayvaish@gmail.com>
Cc: "Vikas Shivappa" <vikas.shivappa@linux.intel.com>
Cc: "Ingo Molnar" <mingo@elte.hu>
Cc: "Borislav Petkov" <bp@suse.de>
Cc: "H. Peter Anvin" <h.peter.anvin@intel.com>
Link: http://lkml.kernel.org/r/1477142405-32078-2-git-send-email-fenghua.yu@intel.comSigned-off-by: NThomas Gleixner <tglx@linutronix.de>

Pull crypto fix from Herbert Xu:
 "This fixes a regression caused by the stack vmalloc change"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  hwrng: core - Don't use a stack buffer in add_early_randomness()

Pull clk fixes from Stephen Boyd:
 "This is the first batch of clk driver fixes for this release.

  We have a handful of fixes for the uniphier clk driver that was
  introduced recently, as well as Kconfig option hiding, module
  autoloading markings, and a few fixes for clk_hw based registration
  patches that went in this merge window"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: at91: Fix a return value in case of error
  clk: uniphier: rename MIO clock to SD clock for Pro5, PXs2, LD20 SoCs
  clk: uniphier: fix memory overrun bug
  clk: hi6220: use CLK_OF_DECLARE_DRIVER for sysctrl and mediactrl clock init
  clk: mvebu: armada-37xx-periph: Fix the clock gate flag
  clk: bcm2835: Clamp the PLL's requested rate to the hardware limits.
  clk: max77686: fix number of clocks setup for clk_hw based registration
  clk: mvebu: armada-37xx-periph: Fix the clock provider registration
  clk: core: add __init decoration for CLK_OF_DECLARE_DRIVER function
  clk: mediatek: Add hardware dependency
  clk: samsung: clk-exynos-audss: Fix module autoload
  clk: uniphier: fix type of variable passed to regmap_read()
  clk: uniphier: add system clock support for sLD3 SoC

Pull GPIO fixes from Linus Walleij:
 "Here is a set of GPIO fixes for the v4.9 kernel series:

   - Fix up off-by one and line offset validation, info leak to
     userspace, and reject invalid flags. Those are especially valuable
     hardening patches from Lars-Peter Clausen, all tagged for stable.

   - Fix module autoload for TS4800 and ATH79.

   - Correct the IRQ handler for MPC8xxx to use handle_level_irq() as it
     (a) reacts to edges not levels and (b) even implements .irq_ack().
     We were missing IRQs here.

   - Fix the error path for acpi_dev_gpio_irq_get()

   - Fix a memory leak in the MXS driver.

   - Fix an annoying typo in the STMPE driver.

   - Put a dependency on sysfs to the mockup driver"

* tag 'gpio-v4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: mpc8xxx: Correct irq handler function
  gpio: ath79: Fix module autoload
  gpio: ts4800: Fix module autoload
  gpio: GPIO_GET_LINEEVENT_IOCTL: Reject invalid line and event flags
  gpio: GPIO_GET_LINEHANDLE_IOCTL: Reject invalid line flags
  gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leak
  gpio: GPIO_GET_LINEEVENT_IOCTL: Validate line offset
  gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leak
  gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offset
  gpio: GPIO_GET_CHIPINFO_IOCTL: Fix information leak
  gpio: GPIO_GET_CHIPINFO_IOCTL: Fix line offset validation
  gpio / ACPI: fix returned error from acpi_dev_gpio_irq_get()
  gpio: mockup: add sysfs dependency
  gpio: stmpe: || vs && typo
  gpio: mxs: Unmap region obtained by of_iomap
  gpio/board.txt: point to gpiod_set_value

Pull xen fixes from David Vrabel:

 - advertise control feature flags in xenstore

 - fix x86 build when XEN_PVHVM is disabled

* tag 'for-linus-4.9-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xenbus: check return value of xenbus_scanf()
  xenbus: prefer list_for_each()
  x86: xen: move cpu_up functions out of ifdef
  xenbus: advertise control feature flags

This patch unexports the low-level __get_user_pages() function.

Recent refactoring of the get_user_pages* functions allow flags to be
passed through get_user_pages() which eliminates the need for access to
this function from its one user, kvm.

We can see that the two calls to get_user_pages() which replace
__get_user_pages() in kvm_main.c are equivalent by examining their call
stacks:

  get_user_page_nowait():
    get_user_pages(start, 1, flags, page, NULL)
    __get_user_pages_locked(current, current->mm, start, 1, page, NULL, NULL,
			    false, flags | FOLL_TOUCH)
    __get_user_pages(current, current->mm, start, 1,
		     flags | FOLL_TOUCH | FOLL_GET, page, NULL, NULL)

  check_user_page_hwpoison():
    get_user_pages(addr, 1, flags, NULL, NULL)
    __get_user_pages_locked(current, current->mm, addr, 1, NULL, NULL, NULL,
			    false, flags | FOLL_TOUCH)
    __get_user_pages(current, current->mm, addr, 1, flags | FOLL_TOUCH, NULL,
		     NULL, NULL)
Signed-off-by: NLorenzo Stoakes <lstoakes@gmail.com>
Acked-by: NPaolo Bonzini <pbonzini@redhat.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Now that Lorenzo cleaned things up and made the FOLL_FORCE users
explicit, it becomes obvious how some of them don't really need
FOLL_FORCE at all.

So remove FOLL_FORCE from the proc code that reads the command line and
arguments from user space.

The mem_rw() function actually does want FOLL_FORCE, because gdd (and
possibly many other debuggers) use it as a much more convenient version
of PTRACE_PEEKDATA, but we should consider making the FOLL_FORCE part
conditional on actually being a ptracer.  This does not actually do
that, just moves adds a comment to that effect and moves the gup_flags
settings next to each other.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Don't ignore errors here: Set backend state to unknown when
unsuccessful.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

This is more efficient than list_for_each_safe() when list modification
is accompanied by breaking out of the loop.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Reviewed-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

Three newly introduced functions are not defined when CONFIG_XEN_PVHVM is
disabled, but are still being used:

arch/x86/xen/enlighten.c:141:12: warning: ‘xen_cpu_up_prepare’ used but never defined
arch/x86/xen/enlighten.c:142:12: warning: ‘xen_cpu_up_online’ used but never defined
arch/x86/xen/enlighten.c:143:12: warning: ‘xen_cpu_dead’ used but never defined

Fixes: 4d737042 ("xen/x86: Convert to hotplug state machine")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

The Xen docs specify several flags which a guest can set to advertise
which values of the xenstore control/shutdown key it will recognize.
This patch adds code to write all the relevant feature-flag keys.
Based-on-patch-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>

From the beginning of the gpio-mpc8xxx.c, the "handle_level_irq"
has being used to handle GPIO interrupts in the PowerPC/Layerscape
platforms. But actually, almost all PowerPC/Layerscape platforms
assert an interrupt request upon either a high-to-low change or
any change on the state of the signal.

So the "handle_level_irq" is not reasonable for PowerPC/Layerscape
GPIO interrupt, it should be "handle_edge_irq". Otherwise the system
may lost some interrupts from the PIN's state changes.
Signed-off-by: NLiu Gang <Gang.Liu@nxp.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Pull UBI[FS] fixes from Richard Weinberger:
 "This contains fixes for issues in both UBI and UBIFS:

   - Fallout from the merge window, refactoring UBI code introduced some
     issues.

   - Fixes for an UBIFS readdir bug which can cause getdents() to busy
     loop for ever and a bug in the UBIFS xattr code"

* tag 'upstream-4.9-rc2' of git://git.infradead.org/linux-ubifs:
  ubifs: Abort readdir upon error
  UBI: Fix crash in try_recover_peb()
  ubi: fix swapped arguments to call to ubi_alloc_aeb
  ubifs: Fix xattr_names length in exit paths
  ubifs: Rename ubifs_rename2

Pull ext4 fixes from Ted Ts'o:
 "A few bug fixes and add some missing KERN_CONT annotations"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: add missing KERN_CONT to a few more debugging uses
  fscrypto: lock inode while setting encryption policy
  ext4: correct endianness conversion in __xattr_check_inode()
  fscrypto: make XTS tweak initialization endian-independent
  ext4: do not advertise encryption support when disabled
  jbd2: fix incorrect unlock on j_list_lock
  ext4: super.c: Update logging style using KERN_CONT

Pull SCSI target fixes from Nicholas Bellinger:
 "Here are the outstanding target-pending fixes for v4.9-rc2.

  This includes:

   - Fix v4.1.y+ reference leak regression with concurrent TMR
     ABORT_TASK + session shutdown. (Vaibhav Tandon)

   - Enable tcm_fc w/ SCF_USE_CPUID to avoid host exchange timeouts
     (Hannes)

   - target/user error sense handling fixes. (Andy + MNC + HCH)

   - Fix iscsi-target NOP_OUT error path iscsi_cmd descriptor leak
     (Varun)

   - Two EXTENDED_COPY SCSI status fixes for ESX VAAI (Dinesh Israni +
     Nixon Vincent)

   - Revert a v4.8 residual overflow change, that breaks sg_inq with
     small allocation lengths.

  There are a number of folks stress testing the v4.1.y regression fix
  in their environments, and more folks doing iser-target I/O stress
  testing atop recent v4.x.y code.

  There is also one v4.2.y+ RCU conversion regression related to
  explicit NodeACL configfs changes, that is still being tracked down"

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target/tcm_fc: use CPU affinity for responses
  target/tcm_fc: Update debugging statements to match libfc usage
  target/tcm_fc: return detailed error in ft_sess_create()
  target/tcm_fc: print command pointer in debug message
  target: fix potential race window in target_sess_cmd_list_waiting()
  Revert "target: Fix residual overflow handling in target_complete_cmd_with_length"
  target: Don't override EXTENDED_COPY xcopy_pt_cmd SCSI status code
  target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLE
  target: Re-add missing SCF_ACK_KREF assignment in v4.1.y
  iscsi-target: fix iscsi cmd leak
  iscsi-target: fix spelling mistake "Unsolicitied" -> "Unsolicited"
  target/user: Fix comments to not refer to data ring
  target/user: Return an error if cmd data size is too large
  target/user: Use sense_reason_t in tcmu_queue_cmd_ring

Merge tag 'hwmon-for-linus-v4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 "Couple of hwmon fixes:

  Fix a potential ERR_PTR dereference in max31790 driver, and handle
  temperature readings below 0 in adm9240 driver"

* tag 'hwmon-for-linus-v4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (max31790) potential ERR_PTR dereference
  hwmon: (adm9240) handle temperature readings below 0

Pull IPMI updates from Corey Minyard:
 "A small bug fix and a new driver for acting as an IPMI device.

  I was on vacation during the merge window (a long vacation) but this
  is a bug fix that should go in and a new driver that shouldn't hurt
  anything.

  This has been in linux-next for a month or so"

* tag 'for-linus-4.9-2' of git://git.code.sf.net/p/openipmi/linux-ipmi:
  ipmi: fix crash on reading version from proc after unregisted bmc
  ipmi/bt-bmc: remove redundant return value check of platform_get_resource()
  ipmi/bt-bmc: add a dependency on ARCH_ASPEED
  ipmi: Fix ioremap error handling in bt-bmc
  ipmi: add an Aspeed BT IPMI BMC driver

If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/gpio/gpio-ath79.ko | grep alias
$

After this patch:

$ modinfo drivers/gpio/gpio-ath79.ko | grep alias
alias:          of:N*T*Cqca,ar9340-gpioC*
alias:          of:N*T*Cqca,ar9340-gpio
alias:          of:N*T*Cqca,ar7100-gpioC*
alias:          of:N*T*Cqca,ar7100-gpio
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Acked-by: NAban Bedel <albeu@free.fr>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Pull timer updates from Thomas Gleixner:
 "This updates contains:

   - A revert which addresses a boot failure on ARM Sun5i platforms

   - A new clocksource driver, which has been delayed beyond rc1 due to
     an interrupt driver issue which was unearthed by this driver. The
     debugging of that issue and the discussion about the proper
     solution made this driver miss the merge window. There is no point
     in delaying it for a full cycle as it completes the basic mainline
     support for the new JCore platform and does not create any risk
     outside of that platform"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init"
  clocksource: Add J-Core timer/clocksource driver
  of: Add J-Core timer bindings

Pull x86 fixes from Ingo Molnar:
 "Three fixes, a hw-enablement and a cross-arch fix/enablement change:

   - SGI/UV fix for older platforms

   - x32 signal handling fix

   - older x86 platform bootup APIC fix

   - AVX512-4VNNIW (Neural Network Instructions) and AVX512-4FMAPS
     (Multiply Accumulation Single precision instructions) enablement.

   - move thread_info back into x86 specific code, to make life easier
     for other architectures trying to make use of
     CONFIG_THREAD_INFO_IN_TASK_STRUCT=y"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/smp: Don't try to poke disabled/non-existent APIC
  sched/core, x86: Make struct thread_info arch specific again
  x86/signal: Remove bogus user_64bit_mode() check from sigaction_compat_abi()
  x86/platform/UV: Fix support for EFI_OLD_MEMMAP after BIOS callback updates
  x86/cpufeature: Add AVX512_4VNNIW and AVX512_4FMAPS features
  x86/vmware: Skip timer_irq_works() check on VMware

Pull vmap stack fixes from Ingo Molnar:
 "This is fallout from CONFIG_HAVE_ARCH_VMAP_STACK=y on x86: stack
  accesses that used to be just somewhat questionable are now totally
  buggy.

  These changes try to do it without breaking the ABI: the fields are
  left there, they are just reporting zero, or reporting narrower
  information (the maps file change)"

* 'mm-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  mm: Change vm_is_stack_for_task() to vm_is_stack_for_current()
  fs/proc: Stop trying to report thread stacks
  fs/proc: Stop reporting eip and esp in /proc/PID/stat
  mm/numa: Remove duplicated include from mprotect.c

Pull irq fixes from Ingo Molnar:
 "Mostly irqchip driver fixes, plus a symbol export"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  kernel/irq: Export irq_set_parent()
  irqchip/gic: Add missing \n to CPU IF adjustment message
  irqchip/jcore: Don't show Kconfig menu item for driver
  irqchip/eznps: Drop pointless static qualifier in nps400_of_init()
  irqchip/gic-v3-its: Fix entry size mask for GITS_BASER
  irqchip/gic-v3-its: Fix 64bit GIC{R,ITS}_TYPER accesses

Pull EFI fixes from Ingo Molnar:
 "Add Ard Biesheuvel as EFI co-maintainer, plus fix an ARM build bug
  with older toolchains"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/arm: Fix absolute relocation detection for older toolchains
  MAINTAINERS: Add myself as EFI maintainer

Apparently trying to poke a disabled or non-existent APIC
leads to a box that doesn't even boot. Let's not do that.

No real clue if this is the right fix, but at least my
P3 machine boots again.
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.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: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: dyoung@redhat.com
Cc: kexec@lists.infradead.org
Cc: stable@vger.kernel.org
Fixes: 2a51fe08 ("arch/x86: Handle non enumerated CPU after physical hotplug")
Link: http://lkml.kernel.org/r/1477102684-5092-1-git-send-email-ville.syrjala@linux.intel.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Pull powerpc fixes from Michael Ellerman:
 "Fixes marked for stable:
   - Prevent unlikely crash in copro_calculate_slb() (Frederic Barrat)
   - cxl: Prevent adapter reset if an active context exists (Vaibhav Jain)

  Fixes for code merged this cycle:
   - Fix boot on systems with uncompressed kernel image (Heiner Kallweit)
   - Drop dump_numa_memory_topology() (Michael Ellerman)
   - Fix numa topology console print (Aneesh Kumar K.V)
   - Ignore the pkey system calls for now (Stephen Rothwell)"

* tag 'powerpc-4.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc: Ignore the pkey system calls for now
  powerpc: Fix numa topology console print
  powerpc/mm: Drop dump_numa_memory_topology()
  cxl: Prevent adapter reset if an active context exists
  powerpc/boot: Fix boot on systems with uncompressed kernel image
  powerpc/mm: Prevent unlikely crash in copro_calculate_slb()

Pull KVM fixes from Radim Krčmář:
 "ARM:
   - avoid livelock when walking guest page tables
   - fix HYP mode static keys without CC_HAVE_ASM_GOTO

  MIPS:
   - fix a build error without TRACEPOINTS_ENABLED

  s390:
   - reject a malformed userspace configuration

  x86:
   - suppress a warning without CONFIG_CPU_FREQ
   - initialize whole irq_eoi array"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  arm/arm64: KVM: Map the BSS at HYP
  arm64: KVM: Take S1 walks into account when determining S2 write faults
  KVM: s390: reject invalid modes for runtime instrumentation
  kvm: x86: memset whole irq_eoi
  kvm/x86: Fix unused variable warning in kvm_timer_init()
  KVM: MIPS: Add missing uaccess.h include