This patch fixes the key_ref leak, removes the unnecessary KEY_FLAG_KEEP
test before setting the flag, and cleans up the if/then brackets style
introduced in commit:
d3600bcf KEYS: prevent keys from being removed from specified keyrings
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>

There is no need to hold the ima_write_mutex for so long.  We only need it
around ima_parse_add_rule().

Changelog:
- The return path now takes into account failed kmalloc() call.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Commit "IMA: policy can now be updated multiple times" assumed that the
policy would be updated at least once.

If there are zero updates, the temporary list head object will get added
to the policy list, and later dereferenced as an IMA policy object, which
means that invalid memory will be accessed.

Changelog:
- Move list_empty() test to ima_release_policy(), before audit msg - Mimi
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The Kconfig currently controlling compilation of this code is:

ima/Kconfig:config IMA_MOK_KEYRING
ima/Kconfig: bool "Create IMA machine owner keys (MOK) and blacklist keyrings"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple of traces of modularity so that when reading the
driver there is no doubt it really is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: linux-ima-devel@lists.sourceforge.net
Cc: linux-ima-user@lists.sourceforge.net
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

While creating a temporary list of new rules, the ima_appraise flag is
updated, but not reverted on failure to append the new rules to the
existing policy.  This patch defines temp_ima_appraise flag.  Only when
the new rules are appended to the policy is the flag updated.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Petko Manolov <petkan@mip-labs.com>

Set the KEY_FLAGS_KEEP on the .ima_blacklist to prevent userspace
from removing keys from the keyring.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Userspace should not be allowed to remove keys from certain keyrings
(eg. blacklist), though the keys themselves can expire.

This patch defines a new key flag named KEY_FLAG_KEEP to prevent
userspace from being able to unlink, revoke, invalidate or timed
out a key on a keyring.  When this flag is set on the keyring, all
keys subsequently added are flagged.

In addition, when this flag is set, the keyring itself can not be
cleared.
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>

It is often useful to be able to read back the IMA policy.  It is
even more important after introducing CONFIG_IMA_WRITE_POLICY.
This option allows the root user to see the current policy rules.
Signed-off-by: Zbigniew Jasinski <z.jasinski@samsung.com>
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This option creates IMA MOK and blacklist keyrings.  IMA MOK is an
intermediate keyring that sits between .system and .ima keyrings,
effectively forming a simple CA hierarchy.  To successfully import a key
into .ima_mok it must be signed by a key which CA is in .system keyring.
On turn any key that needs to go in .ima keyring must be signed by CA in
either .system or .ima_mok keyrings. IMA MOK is empty at kernel boot.

IMA blacklist keyring contains all revoked IMA keys.  It is consulted
before any other keyring.  If the search is successful the requested
operation is rejected and error is returned to the caller.
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The new rules get appended to the original policy, forming a queue.
The new rules are first added to a temporary list, which on error
get released without disturbing the normal IMA operations.  On
success both lists (the current policy and the new rules) are spliced.

IMA policy reads are many orders of magnitude more numerous compared to
writes, the match code is RCU protected.  The updater side also does
list splice in RCU manner.
Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The newly added EVM_LOAD_X509 code can be configured even if
CONFIG_EVM is disabled, but that causes a link error:

security/built-in.o: In function `integrity_load_keys':
digsig_asymmetric.c:(.init.text+0x400): undefined reference to `evm_load_x509'

This adds a Kconfig dependency to ensure it is only enabled when
CONFIG_EVM is set as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 2ce523eb ("evm: load x509 certificate from the kernel")
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

The EVM verification status is cached in iint->evm_status and if it
was successful, never re-verified again when IMA passes the 'iint' to
evm_verifyxattr().

When file attributes or extended attributes change, we may wish to
re-verify EVM integrity as well.  For example, after setting a digital
signature we may need to re-verify the signature and update the
iint->flags that there is an EVM signature.

This patch enables that by resetting evm_status to INTEGRITY_UKNOWN
state.

Changes in v2:
* Flag setting moved to EVM layer
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

A crypto HW kernel module can possibly initialize the EVM key from the
kernel __init code to enable EVM before calling the 'init' process.
This patch provides a function evm_set_key() to set the EVM key
directly without using the KEY subsystem.

Changes in v4:
* kernel-doc style for evm_set_key

Changes in v3:
* error reporting moved to evm_set_key
* EVM_INIT_HMAC moved to evm_set_key
* added bitop to prevent key setting race

Changes in v2:
* use size_t for key size instead of signed int
* provide EVM_MAX_KEY_SIZE macro in <linux/evm.h>
* provide EVM_MIN_KEY_SIZE macro in <linux/evm.h>
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

In order to enable EVM before starting the 'init' process,
evm_initialized needs to be non-zero.  Previously non-zero indicated
that the HMAC key was loaded.  When EVM loads the X509 before calling
'init', with this patch it is now possible to enable EVM to start
signature based verification.

This patch defines bits to enable EVM if a key of any type is loaded.

Changes in v3:
* print error message if key is not set

Changes in v2:
* EVM_STATE_KEY_SET replaced by EVM_INIT_HMAC
* EVM_STATE_X509_SET replaced by EVM_INIT_X509
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

This patch defines a configuration option and the evm_load_x509() hook
to load an X509 certificate onto the EVM trusted kernel keyring.

Changes in v4:
* Patch description updated

Changes in v3:
* Removed EVM_X509_PATH definition. CONFIG_EVM_X509_PATH is used
  directly.

Changes in v2:
* default key patch changed to /etc/keys
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Require all keys added to the EVM keyring be signed by an
existing trusted key on the system trusted keyring.

This patch also switches IMA to use integrity_init_keyring().

Changes in v3:
* Added 'init_keyring' config based variable to skip initializing
  keyring instead of using  __integrity_init_keyring() wrapper.
* Added dependency back to CONFIG_IMA_TRUSTED_KEYRING

Changes in v2:
* Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common
  CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option
* Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config
  file compatibility. (Mimi Zohar)
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

Merge slub bulk allocator updates from Andrew Morton:
 "This missed the merge window because I was waiting for some repairs to
  come in.  Nothing actually uses the bulk allocator yet and the changes
  to other code paths are pretty small.  And the net guys are waiting
  for this so they can start merging the client code"

More comments from Jesper Dangaard Brouer:
 "The kmem_cache_alloc_bulk() call, in mm/slub.c, were included in
  previous kernel.  The present version contains a bug.  Vladimir
  Davydov noticed it contained a bug, when kernel is compiled with
  CONFIG_MEMCG_KMEM (see commit 03ec0ed5: "slub: fix kmem cgroup
  bug in kmem_cache_alloc_bulk").  Plus the mem cgroup counterpart in
  kmem_cache_free_bulk() were missing (see commit 03374518 "slub:
  add missing kmem cgroup support to kmem_cache_free_bulk").

  I don't consider the fix stable-material because there are no in-tree
  users of the API.

  But with known bugs (for memcg) I cannot start using the API in the
  net-tree"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  slab/slub: adjust kmem_cache_alloc_bulk API
  slub: add missing kmem cgroup support to kmem_cache_free_bulk
  slub: fix kmem cgroup bug in kmem_cache_alloc_bulk
  slub: optimize bulk slowpath free by detached freelist
  slub: support for bulk free with SLUB freelists

Pull tty/serial fixes from Greg KH:
 "Here are a few small tty/serial driver fixes for 4.4-rc2 that resolve
  some reported problems.

  All have been in linux-next, full details are in the shortlog below"

* tag 'tty-4.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: export fsl8250_handle_irq
  serial: 8250_mid: Add missing dependency
  tty: audit: Fix audit source
  serial: etraxfs-uart: Fix crash
  serial: fsl_lpuart: Fix earlycon support
  bcm63xx_uart: Use the device name when registering an interrupt
  tty: Fix direct use of tty buffer work
  tty: Fix tty_send_xchar() lock order inversion

Pull staging/IIO fixes from Greg KH:
 "Here are some staging and iio driver fixes for 4.4-rc2.  All of these
  are in response to issues that have been reported and have been in
  linux-next for a while"

* tag 'staging-4.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  Revert "Staging: wilc1000: coreconfigurator: Drop unneeded wrapper functions"
  iio: adc: xilinx: Fix VREFN scale
  iio: si7020: Swap data byte order
  iio: adc: vf610_adc: Fix division by zero error
  iio:ad7793: Fix ad7785 product ID
  iio: ad5064: Fix ad5629/ad5669 shift
  iio:ad5064: Make sure ad5064_i2c_write() returns 0 on success
  iio: lpc32xx_adc: fix warnings caused by enabling unprepared clock
  staging: iio: select IRQ_WORK for IIO_DUMMY_EVGEN
  vf610_adc: Fix internal temperature calculation

Pull USB fixes from Greg KH:
 "Here are a number of USB fixes and new device ids for 4.4-rc2.  All
  have been in linux-next and the details are in the shortlog"

* tag 'usb-4.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (28 commits)
  usblp: do not set TASK_INTERRUPTIBLE before lock
  USB: MAINTAINERS: cxacru
  usb: kconfig: fix warning of select USB_OTG
  USB: option: add XS Stick W100-2 from 4G Systems
  xhci: Fix a race in usb2 LPM resume, blocking U3 for usb2 devices
  usb: xhci: fix checking ep busy for CFC
  xhci: Workaround to get Intel xHCI reset working more reliably
  usb: chipidea: imx: fix a possible NULL dereference
  usb: chipidea: usbmisc_imx: fix a possible NULL dereference
  usb: chipidea: otg: gadget module load and unload support
  usb: chipidea: debug: disable usb irq while role switch
  ARM: dts: imx27.dtsi: change the clock information for usb
  usb: chipidea: imx: refine clock operations to adapt for all platforms
  usb: gadget: atmel_usba_udc: Expose correct device speed
  usb: musb: enable usb_dma parameter
  usb: phy: phy-mxs-usb: fix a possible NULL dereference
  usb: dwc3: gadget: let us set lower max_speed
  usb: musb: fix tx fifo flush handling
  usb: gadget: f_loopback: fix the warning during the enumeration
  usb: dwc2: host: Fix remote wakeup when not in DWC2_L2
  ...

Pull MIPS fixes from Ralf Baechle:

 - Fix a flood of annoying build warnings

 - A number of fixes for Atheros 79xx platforms

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: ath79: Add a machine entry for booting OF machines
  MIPS: ath79: Fix the size of the MISC INTC registers in ar9132.dtsi
  MIPS: ath79: Fix the DDR control initialization on ar71xx and ar934x
  MIPS: Fix flood of warnings about comparsion being always true.

Pull parisc update from Helge Deller:
 "This patchset adds Huge Page and HUGETLBFS support for parisc"

Honestly, the hugepage support should have gone through in the merge
window, and is not really an rc-time fix.  But it only touches
arch/parisc, and I cannot find it in myself to care.  If one of the
three parisc users notices a breakage, I will point at Helge and make
rude farting noises.

* 'parisc-4.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Map kernel text and data on huge pages
  parisc: Add Huge Page and HUGETLBFS support
  parisc: Use long branch to do_syscall_trace_exit
  parisc: Increase initial kernel mapping to 32MB on 64bit kernel
  parisc: Initialize the fault vector earlier in the boot process.
  parisc: Add defines for Huge page support
  parisc: Drop unused MADV_xxxK_PAGES flags from asm/mman.h
  parisc: Drop definition of start_thread_som for HP-UX SOM binaries
  parisc: Fix wrong comment regarding first pmd entry flags

Pull perf tool fixes from Thomas Gleixner:
 "A couple of fixes for perf tools:

   - Build system updates

   - Plug a memory leak in an error path of perf probe

   - Tear down probes correctly when adding fails

   - Fixes to the perf symbol handling

   - Fix ordering of event processing in buildid-list

   - Fix per DSO filtering in the histogram browser"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf probe: Clear probe_trace_event when add_probe_trace_event() fails
  perf probe: Fix memory leaking on failure by clearing all probe_trace_events
  perf inject: Also re-pipe lost_samples event
  perf buildid-list: Requires ordered events
  perf symbols: Fix dso lookup by long name and missing buildids
  perf symbols: Allow forcing reading of non-root owned files by root
  perf hists browser: The dso can be obtained from popup_action->ms.map->dso
  perf hists browser: Fix 'd' hotkey action to filter by DSO
  perf symbols: Rebuild rbtree when adjusting symbols for kcore
  tools: Add a "make all" rule
  tools: Actually install tmon in the install rule

Pull x86 fixes from Thomas Gleixner:
 "This update contains:

   - MPX updates for handling 32bit processes

   - A fix for a long standing bug in 32bit signal frame handling
     related to FPU/XSAVE state

   - Handle get_xsave_addr() correctly in KVM

   - Fix SMAP check under paravirtualization

   - Add a comment to the static function trace entry to avoid further
     confusion about the difference to dynamic tracing"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpu: Fix SMAP check in PVOPS environments
  x86/ftrace: Add comment on static function tracing
  x86/fpu: Fix get_xsave_addr() behavior under virtualization
  x86/fpu: Fix 32-bit signal frame handling
  x86/mpx: Fix 32-bit address space calculation
  x86/mpx: Do proper get_user() when running 32-bit binaries on 64-bit kernels

Adjust kmem_cache_alloc_bulk API before we have any real users.

Adjust API to return type 'int' instead of previously type 'bool'.  This
is done to allow future extension of the bulk alloc API.

A future extension could be to allow SLUB to stop at a page boundary, when
specified by a flag, and then return the number of objects.

The advantage of this approach, would make it easier to make bulk alloc
run without local IRQs disabled.  With an approach of cmpxchg "stealing"
the entire c->freelist or page->freelist.  To avoid overshooting we would
stop processing at a slab-page boundary.  Else we always end up returning
some objects at the cost of another cmpxchg.

To keep compatible with future users of this API linking against an older
kernel when using the new flag, we need to return the number of allocated
objects with this API change.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Initial implementation missed support for kmem cgroup support in
kmem_cache_free_bulk() call, add this.

If CONFIG_MEMCG_KMEM is not enabled, the compiler should be smart enough
to not add any asm code.

Incoming bulk free objects can belong to different kmem cgroups, and
object free call can happen at a later point outside memcg context.  Thus,
we need to keep the orig kmem_cache, to correctly verify if a memcg object
match against its "root_cache" (s->memcg_params.root_cache).
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The call slab_pre_alloc_hook() interacts with kmemgc and is not allowed to
be called several times inside the bulk alloc for loop, due to the call to
memcg_kmem_get_cache().

This would result in hitting the VM_BUG_ON in __memcg_kmem_get_cache.

As suggested by Vladimir Davydov, change slab_post_alloc_hook() to be able
to handle an array of objects.

A subtle detail is, loop iterator "i" in slab_post_alloc_hook() must have
same type (size_t) as size argument.  This helps the compiler to easier
realize that it can remove the loop, when all debug statements inside loop
evaluates to nothing.  Note, this is only an issue because the kernel is
compiled with GCC option: -fno-strict-overflow

In slab_alloc_node() the compiler inlines and optimizes the invocation of
slab_post_alloc_hook(s, flags, 1, &object) by removing the loop and access
object directly.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reported-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This change focus on improving the speed of object freeing in the
"slowpath" of kmem_cache_free_bulk.

The calls slab_free (fastpath) and __slab_free (slowpath) have been
extended with support for bulk free, which amortize the overhead of
the (locked) cmpxchg_double.

To use the new bulking feature, we build what I call a detached
freelist.  The detached freelist takes advantage of three properties:

 1) the free function call owns the object that is about to be freed,
    thus writing into this memory is synchronization-free.

 2) many freelist's can co-exist side-by-side in the same slab-page
    each with a separate head pointer.

 3) it is the visibility of the head pointer that needs synchronization.

Given these properties, the brilliant part is that the detached
freelist can be constructed without any need for synchronization.  The
freelist is constructed directly in the page objects, without any
synchronization needed.  The detached freelist is allocated on the
stack of the function call kmem_cache_free_bulk.  Thus, the freelist
head pointer is not visible to other CPUs.

All objects in a SLUB freelist must belong to the same slab-page.
Thus, constructing the detached freelist is about matching objects
that belong to the same slab-page.  The bulk free array is scanned is
a progressive manor with a limited look-ahead facility.

Kmem debug support is handled in call of slab_free().

Notice kmem_cache_free_bulk no longer need to disable IRQs. This
only slowed down single free bulk with approx 3 cycles.

Performance data:
 Benchmarked[1] obj size 256 bytes on CPU i7-4790K @ 4.00GHz

SLUB fastpath single object quick reuse: 47 cycles(tsc) 11.931 ns

To get stable and comparable numbers, the kernel have been booted with
"slab_merge" (this also improve performance for larger bulk sizes).

Performance data, compared against fallback bulking:

bulk -  fallback bulk            - improvement with this patch
   1 -  62 cycles(tsc) 15.662 ns - 49 cycles(tsc) 12.407 ns- improved 21.0%
   2 -  55 cycles(tsc) 13.935 ns - 30 cycles(tsc) 7.506 ns - improved 45.5%
   3 -  53 cycles(tsc) 13.341 ns - 23 cycles(tsc) 5.865 ns - improved 56.6%
   4 -  52 cycles(tsc) 13.081 ns - 20 cycles(tsc) 5.048 ns - improved 61.5%
   8 -  50 cycles(tsc) 12.627 ns - 18 cycles(tsc) 4.659 ns - improved 64.0%
  16 -  49 cycles(tsc) 12.412 ns - 17 cycles(tsc) 4.495 ns - improved 65.3%
  30 -  49 cycles(tsc) 12.484 ns - 18 cycles(tsc) 4.533 ns - improved 63.3%
  32 -  50 cycles(tsc) 12.627 ns - 18 cycles(tsc) 4.707 ns - improved 64.0%
  34 -  96 cycles(tsc) 24.243 ns - 23 cycles(tsc) 5.976 ns - improved 76.0%
  48 -  83 cycles(tsc) 20.818 ns - 21 cycles(tsc) 5.329 ns - improved 74.7%
  64 -  74 cycles(tsc) 18.700 ns - 20 cycles(tsc) 5.127 ns - improved 73.0%
 128 -  90 cycles(tsc) 22.734 ns - 27 cycles(tsc) 6.833 ns - improved 70.0%
 158 -  99 cycles(tsc) 24.776 ns - 30 cycles(tsc) 7.583 ns - improved 69.7%
 250 - 104 cycles(tsc) 26.089 ns - 37 cycles(tsc) 9.280 ns - improved 64.4%

Performance data, compared current in-kernel bulking:

bulk - curr in-kernel  - improvement with this patch
   1 -  46 cycles(tsc) - 49 cycles(tsc) - improved (cycles:-3) -6.5%
   2 -  27 cycles(tsc) - 30 cycles(tsc) - improved (cycles:-3) -11.1%
   3 -  21 cycles(tsc) - 23 cycles(tsc) - improved (cycles:-2) -9.5%
   4 -  18 cycles(tsc) - 20 cycles(tsc) - improved (cycles:-2) -11.1%
   8 -  17 cycles(tsc) - 18 cycles(tsc) - improved (cycles:-1) -5.9%
  16 -  18 cycles(tsc) - 17 cycles(tsc) - improved (cycles: 1)  5.6%
  30 -  18 cycles(tsc) - 18 cycles(tsc) - improved (cycles: 0)  0.0%
  32 -  18 cycles(tsc) - 18 cycles(tsc) - improved (cycles: 0)  0.0%
  34 -  78 cycles(tsc) - 23 cycles(tsc) - improved (cycles:55) 70.5%
  48 -  60 cycles(tsc) - 21 cycles(tsc) - improved (cycles:39) 65.0%
  64 -  49 cycles(tsc) - 20 cycles(tsc) - improved (cycles:29) 59.2%
 128 -  69 cycles(tsc) - 27 cycles(tsc) - improved (cycles:42) 60.9%
 158 -  79 cycles(tsc) - 30 cycles(tsc) - improved (cycles:49) 62.0%
 250 -  86 cycles(tsc) - 37 cycles(tsc) - improved (cycles:49) 57.0%

Performance with normal SLUB merging is significantly slower for
larger bulking.  This is believed to (primarily) be an effect of not
having to share the per-CPU data-structures, as tuning per-CPU size
can achieve similar performance.

bulk - slab_nomerge   -  normal SLUB merge
   1 -  49 cycles(tsc) - 49 cycles(tsc) - merge slower with cycles:0
   2 -  30 cycles(tsc) - 30 cycles(tsc) - merge slower with cycles:0
   3 -  23 cycles(tsc) - 23 cycles(tsc) - merge slower with cycles:0
   4 -  20 cycles(tsc) - 20 cycles(tsc) - merge slower with cycles:0
   8 -  18 cycles(tsc) - 18 cycles(tsc) - merge slower with cycles:0
  16 -  17 cycles(tsc) - 17 cycles(tsc) - merge slower with cycles:0
  30 -  18 cycles(tsc) - 23 cycles(tsc) - merge slower with cycles:5
  32 -  18 cycles(tsc) - 22 cycles(tsc) - merge slower with cycles:4
  34 -  23 cycles(tsc) - 22 cycles(tsc) - merge slower with cycles:-1
  48 -  21 cycles(tsc) - 22 cycles(tsc) - merge slower with cycles:1
  64 -  20 cycles(tsc) - 48 cycles(tsc) - merge slower with cycles:28
 128 -  27 cycles(tsc) - 57 cycles(tsc) - merge slower with cycles:30
 158 -  30 cycles(tsc) - 59 cycles(tsc) - merge slower with cycles:29
 250 -  37 cycles(tsc) - 56 cycles(tsc) - merge slower with cycles:19

Joint work with Alexander Duyck.

[1] https://github.com/netoptimizer/prototype-kernel/blob/master/kernel/mm/slab_bulk_test01.c

[akpm@linux-foundation.org: BUG_ON -> WARN_ON;return]
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Make it possible to free a freelist with several objects by adjusting API
of slab_free() and __slab_free() to have head, tail and an objects counter
(cnt).

Tail being NULL indicate single object free of head object.  This allow
compiler inline constant propagation in slab_free() and
slab_free_freelist_hook() to avoid adding any overhead in case of single
object free.

This allows a freelist with several objects (all within the same
slab-page) to be free'ed using a single locked cmpxchg_double in
__slab_free() and with an unlocked cmpxchg_double in slab_free().

Object debugging on the free path is also extended to handle these
freelists.  When CONFIG_SLUB_DEBUG is enabled it will also detect if
objects don't belong to the same slab-page.

These changes are needed for the next patch to bulk free the detached
freelists it introduces and constructs.

Micro benchmarking showed no performance reduction due to this change,
when debugging is turned off (compiled with CONFIG_SLUB_DEBUG).
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Adjust the linker script and map_pages() to map kernel text and data on
physical 1MB huge/large pages.
Signed-off-by: Helge Deller <deller@gmx.de>

This patch adds huge page support to allow userspace to allocate huge
pages and to use hugetlbfs filesystem on 32- and 64-bit Linux kernels.
A later patch will add kernel support to map kernel text and data on
huge pages.

The only requirement is, that the kernel needs to be compiled for a
PA8X00 CPU (PA2.0 architecture). Older PA1.X CPUs do not support
variable page sizes. 64bit Kernels are compiled for PA2.0 by default.

Technically on parisc multiple physical huge pages may be needed to
emulate standard 2MB huge pages.
Signed-off-by: Helge Deller <deller@gmx.de>

Use the 22bit instead of the 17bit branch instruction on a 64bit kernel
to reach the do_syscall_trace_exit function from the gateway page.
A huge page enabled kernel may need the additional branch distance bits.
Signed-off-by: Helge Deller <deller@gmx.de>

For the 64bit kernel the initially 16 MB kernel memory might become too
small if you build a kernel with many modules built-in and with kernel
text and data areas mapped on huge pages.

This patch increases the initial mapping to 32MB for 64bit kernels and
keeps 16MB for 32bit kernels.
Signed-off-by: Helge Deller <deller@gmx.de>

A fault vector on parisc needs to be 2K aligned.  Furthermore the
checksum of the fault vector needs to sum up to 0 which is being
calculated and written at runtime.

Up to now we aligned both PA20 and PA11 fault vectors on the same 4K
page in order to easily write the checksum after having mapped the
kernel read-only (by mapping this page only as read-write).
But when we want to map the kernel text and data on huge pages this
makes things harder.
So, simplify it by aligning both fault vectors on 2K boundries and write
the checksum before we map the page read-only.
Signed-off-by: Helge Deller <deller@gmx.de>

Huge pages on parisc will have the same size as one pmd table, which
is on a 64bit kernel 2MB on a kernel with 4K kernel page sizes, and
on a 32bit kernel 4MB when used with 4K kernel pages.

Since parisc does not physically supports 2MB huge page sizes, emulate
it with two consecutive 1MB page sizes instead. Keeping the same huge
page size as one pmd will allow us to add transparent huge page support
later on.

Bit 21 in the pte flags was unused and will now be used to mark a page
as huge page (_PAGE_HPAGE_BIT).
Signed-off-by: Helge Deller <deller@gmx.de>

Drop the MADV_xxK_PAGES flags, which were never used and were from a proposed
API which was never integrated into the generic Linux kernel code.

Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>

Merge misc fixes from Andrew Morton:
 "A bunch of fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  slub: mark the dangling ifdef #else of CONFIG_SLUB_DEBUG
  slub: avoid irqoff/on in bulk allocation
  slub: create new ___slab_alloc function that can be called with irqs disabled
  mm: fix up sparse warning in gfpflags_allow_blocking
  ocfs2: fix umask ignored issue
  PM/OPP: add entry in MAINTAINERS
  kernel/panic.c: turn off locks debug before releasing console lock
  kernel/signal.c: unexport sigsuspend()
  kasan: fix kmemleak false-positive in kasan_module_alloc()
  fat: fix fake_offset handling on error path
  mm/hugetlbfs: fix bugs in fallocate hole punch of areas with holes
  mm/page-writeback.c: initialize m_dirty to avoid compile warning
  various: fix pci_set_dma_mask return value checking
  mm: loosen MADV_NOHUGEPAGE to enable Qemu postcopy on s390
  mm: vmalloc: don't remove inexistent guard hole in remove_vm_area()
  tools/vm/page-types.c: support KPF_IDLE
  ncpfs: don't allow negative timeouts
  configfs: allow dynamic group creation
  MAINTAINERS: add Moritz as reviewer for FPGA Manager Framework
  slab.h: sprinkle __assume_aligned attributes

Pull timer fixes from Thomas Gleixner:
 "Two timer fixlets from Arnd:

   - Use proper constant size in the FSL timer driver
   - Prevent a build error for legacy platforms"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource: Disallow drivers for ARCH_USES_GETTIMEOFFSET
  clocksource/fsl: Avoid harmless 64-bit warnings