Convert the Samsung SoC (S3C24xx, S3C64xx, S5Pv210, Exynos) pin
controller bindings to DT schema format.  Parts of description and DTS
example was copied from existing sources, so keep the license as
GPL-2.0-only.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220111201722.327219-18-krzysztof.kozlowski@canonical.com

frontswap_shrink is never called, so remove it.

Link: https://lkml.kernel.org/r/20211224062246.1258487-5-hch@lst.de


Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

frontswap_writethrough is never called, so remove it.

Link: https://lkml.kernel.org/r/20211224062246.1258487-3-hch@lst.de


Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch series "remove Xen tmem leftovers".

Since the removal of the Xen tmem driver in 2019, the cleancache hooks
are entirely unused, as are large parts of frontswap.  This series
against linux-next (with the folio changes included) removes
cleancaches, and cuts down frontswap to the bits actually used by zswap.

This patch (of 13):

The cleancache subsystem is unused since the removal of Xen tmem driver
in commit 814bbf49 ("xen: remove tmem driver").

[akpm@linux-foundation.org: remove now-unreachable code]

Link: https://lkml.kernel.org/r/20211224062246.1258487-1-hch@lst.de
Link: https://lkml.kernel.org/r/20211224062246.1258487-2-hch@lst.de


Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Adjust the path of the ABI files for firewire.rst to prevent a
documentation build error. Prevents this problem:

Sphinx parallel build error:
docutils.utils.SystemMessage: Documentation/driver-api/firewire.rst:22: (SEVERE/4) Problems with "include" directive path:
InputError: [Errno 2] No such file or directory: '../Documentation/driver-api/ABI/stable/firewire-cdev'.

Fixes: 2f4830ef ("FireWire: add driver-api Introduction section")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Akira Yokosawa <akiyks@gmail.com>
Link: https://lore.kernel.org/r/20220119033905.4779-1-rdunlap@infradead.org


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Enric Balletbo i Serra emails bounce:

  <enric.balletbo@collabora.com>: Recipient address rejected: User unknown in  local recipient table

so drop him from the maintainers, similarly to commit 3119c286
("MAINTAINERS: Chrome: Drop Enric Balletbo i Serra").

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Enric Balletbo i Serra <eballetbo@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220120104009.159147-2-krzysztof.kozlowski@canonical.com

Enric Balletbo i Serra emails bounce:

  <enric.balletbo@collabora.com>: Recipient address rejected: User unknown in  local recipient table

so drop him from the maintainers, similarly to commit 3119c286
("MAINTAINERS: Chrome: Drop Enric Balletbo i Serra").  Add generic DRM
bridge maintainers to Analogix ANX7814.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Enric Balletbo i Serra <eballetbo@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220120104009.159147-1-krzysztof.kozlowski@canonical.com

The 'interrupts' properties takes an irq number, not a phandle, and
'interrupt-parent' isn't needed in examples.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20220119015611.2442819-1-robh@kernel.org

The YAML DT encoding has leaked into some array properties. Properties
which are defined as an array should have a schema that's just an array.
That means there should only be a single level of 'minItems',
'maxItems', and/or 'items'.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20220119015627.2443334-1-robh@kernel.org

For a single pinctrl mode, it is not necessary to define pinctrl
properties as the tools always allow pinctrl properties.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20220119015325.2438277-1-robh@kernel.org

Use the api number 134 for KVM_GET_XSAVE2, instead of 42, which has been
used by KVM_GET_XSAVE.
Also, fix the WARNINGs of the underlines being too short.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Message-Id: <20220120045003.315177-1-wei.w.wang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Add thrashing page cache and direct compact related descriptions and
update the usage of getdelays userspace utility.

The following patches modifications have been updated:
https://lore.kernel.org/all/20190312102002.31737-4-jinpuwang@gmail.com/
https://lore.kernel.org/all/1638619795-71451-1-git-send-email-
wang.yong12@zte.com.cn/

Link: https://lkml.kernel.org/r/1639583021-92977-1-git-send-email-wang.yong12@zte.com.cn


Signed-off-by: wangyong <wang.yong12@zte.com.cn>
Reviewed-by: Yang Yang <yang.yang29@zte.com.cn>
Reported-by: Zeal Robot <zealci@zte.com.cn>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Now that KASAN_SHADOW_OFFSET is defined at compile time as a config,
this value must remain constant whatever the size of the virtual address
space, which is only possible by pushing this region at the end of the
address space next to the kernel mapping.

Signed-off-by: Alexandre Ghiti <alexandre.ghiti@canonical.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

Update FMan binding documentation with the newly added workaround for
erratum A-009885.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Each independent example should be a separate entry. This allows for
'interrupts' to have different cell sizes.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220106182518.1435497-7-robh@kernel.org

Each independent example should be a separate entry. This and dropping
'interrupt-parent' allows for 'interrupts' to have different cell sizes.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220106182518.1435497-6-robh@kernel.org

With 'unevaluatedProperties' support enabled, several SPI based display
binding examples have warnings:

Documentation/devicetree/bindings/display/panel/samsung,ld9040.example.dt.yaml: lcd@0: Unevaluated properties are not allowed ('#address-cells', '#size-cells', 'spi-max-frequency', 'spi-cpol', 'spi-cpha' were unexpected)
Documentation/devicetree/bindings/display/panel/kingdisplay,kd035g6-54nt.example.dt.yaml: panel@0: Unevaluated properties are not allowed ('spi-max-frequency', 'spi-3wire' were unexpected)
Documentation/devicetree/bindings/display/panel/ilitek,ili9322.example.dt.yaml: display@0: Unevaluated properties are not allowed ('reg' was unexpected)
Documentation/devicetree/bindings/display/panel/samsung,s6e63m0.example.dt.yaml: display@0: Unevaluated properties are not allowed ('spi-max-frequency' was unexpected)
Documentation/devicetree/bindings/display/panel/abt,y030xx067a.example.dt.yaml: panel@0: Unevaluated properties are not allowed ('spi-max-frequency' was unexpected)
Documentation/devicetree/bindings/display/panel/sony,acx565akm.example.dt.yaml: panel@2: Unevaluated properties are not allowed ('spi-max-frequency', 'reg' were unexpected)
Documentation/devicetree/bindings/display/panel/tpo,td.example.dt.yaml: panel@0: Unevaluated properties are not allowed ('spi-max-frequency', 'spi-cpol', 'spi-cpha' were unexpected)
Documentation/devicetree/bindings/display/panel/lgphilips,lb035q02.example.dt.yaml: panel@0: Unevaluated properties are not allowed ('reg', 'spi-max-frequency', 'spi-cpol', 'spi-cpha' were unexpected)
Documentation/devicetree/bindings/display/panel/innolux,ej030na.example.dt.yaml: panel@0: Unevaluated properties are not allowed ('spi-max-frequency' was unexpected)
Documentation/devicetree/bindings/display/panel/sitronix,st7789v.example.dt.yaml: panel@0: Unevaluated properties are not allowed ('spi-max-frequency', 'spi-cpol', 'spi-cpha' were unexpected)

Fix all of these by adding a reference to spi-peripheral-props.yaml.
With this, the description that the binding must follow
spi-controller.yaml is both a bit out of date and redundant, so remove
it.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://lore.kernel.org/r/20211221125209.1195932-1-robh@kernel.org

Cleanup double spaces in some of the comments.

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/13b3f66efd3b20f1d9bbb9eff1eca00757ac5367.1642080090.git.stano.jakubek@gmail.com

sparkfun,qwiic-joystick and st,24c256 had their comments incorrectly
swapped. Swap them to make them correct.

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/7dc6ddb0b042cd243b2875e9aea81cad541d1c6b.1642080090.git.stano.jakubek@gmail.com

The vendor prefix for Wingtech [1] is used in device tree [2], but was
not documented so far. Add it to the schema to document it.

[1] http://www.wingtech.com/en


[2] arch/arm64/boot/dts/qcom/msm8916-wingtech-wt88047.dts

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220113103110.GA4488@standask-GA-A55M-S2HP

The vendor prefix for Thundercomm [1] is used in device tree [2], but
was not documented so far. Add it to the schema to document it.

[1] https://www.thundercomm.com/


[2] arch/arm64/boot/dts/qcom/sdm845-db845c.dts

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220113103036.GA4456@standask-GA-A55M-S2HP

The vendor prefix for Huawei [1] is used in device trees [2][3], but was
not documented so far. Add it to the schema to document it.

[1] https://www.huawei.com/en/


[2] arch/arm64/boot/dts/qcom/msm8916-huawei-g7.dts
[3] arch/arm64/boot/dts/qcom/msm8994-angler-rev-101.dts

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220113103005.GA4421@standask-GA-A55M-S2HP

The vendor prefix for F(x)tec [1] is used in device tree [2], but was
not documented so far. Add it to the schema to document it.

[1] https://www.fxtec.com/


[2] arch/arm64/boot/dts/qcom/msm8998-fxtec-pro1.dts

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220113102926.GA4388@standask-GA-A55M-S2HP

The vendor prefix for 8devices [1] is used in device tree [2], but was
not documented so far. Add it to the schema to document it.

[1] https://www.8devices.com/


[2] arch/arm/boot/dts/qcom-ipq4018-jalapeno.dts

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220113102842.GA4357@standask-GA-A55M-S2HP

Commit bcd56fe1 ("power: reset: gpio-restart: increase priority
slightly") changed the default restart priority 129, but did not update
the documentation. Correct this, so the driver and documentation have
the same default value.

Signed-off-by: Sander Vanheule <sander@svanheule.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220110214456.67087-1-sander@svanheule.net

The sentence looks ambiguous, rephrase it by adding ", there".

Signed-off-by: Huichun Feng <foxhoundsk.tw@gmail.com>
Signed-off-by: Ching-Chun (Jim) Huang <jserv@ccns.ncku.edu.tw>
Signed-off-by: Chun-Hung Tseng <henrybear327@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20220111052000.2675944-1-foxhoundsk.tw@gmail.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Signed-off-by: Wang Cheng <wanngchenng@gmail.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220115125236.34886-1-wanngchenng@gmail.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>

This updates DAMON debugfs interface for statistics of schemes
successfully applied regions and time/space quota limit exceeds counts.

Link: https://lkml.kernel.org/r/20211210150016.35349-7-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds descriptions for the DAMON_RECLAIM statistics parameters.

Link: https://lkml.kernel.org/r/20211210150016.35349-5-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The DAMON debugfs usage document is missing descriptions for
'kdamond_pid', 'mk_contexts', and 'rm_contexts' debugfs files.  This
commit adds those.

Link: https://lkml.kernel.org/r/20211209131806.19317-6-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

To get detailed monitoring results from the user space, users need to
use the damon_aggregated tracepoint.  This commit adds a brief mention
of it at the beginning of the usage document.

Link: https://lkml.kernel.org/r/20211209131806.19317-5-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

DAMON usage document mentions DAMON user space tool and programming
interface twice.  This commit integrates those and remove unnecessary
part.

Link: https://lkml.kernel.org/r/20211209131806.19317-4-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

DAMOS features including time/space quota limits and watermarks are not
described in the DAMON debugfs interface document.  This commit updates
the document for the features.

Link: https://lkml.kernel.org/r/20211209131806.19317-3-sj@kernel.org


Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Correct the migration stats for hugetlb with using compound_nr() instead
of thp_nr_pages(), meanwhile change 'nr_failed_pages' to record the
number of normal pages failed to migrate, including THP and hugetlb, and
'nr_succeeded' will record the number of normal pages migrated
successfully.

[baolin.wang@linux.alibaba.com: fix docs, per Mike]
  Link: https://lkml.kernel.org/r/141bdfc6-f898-3cc3-f692-726c5f6cb74d@linux.alibaba.com

Link: https://lkml.kernel.org/r/71a4b6c22f208728fe8c78ad26375436c4ff9704.1636275127.git.baolin.wang@linux.alibaba.com


Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This syscall can be used to set a home node for the MPOL_BIND and
MPOL_PREFERRED_MANY memory policy.  Users should use this syscall after
setting up a memory policy for the specified range as shown below.

  mbind(p, nr_pages * page_size, MPOL_BIND, new_nodes->maskp,
        new_nodes->size + 1, 0);
  sys_set_mempolicy_home_node((unsigned long)p, nr_pages * page_size,
				home_node, 0);

The syscall allows specifying a home node/preferred node from which
kernel will fulfill memory allocation requests first.

For address range with MPOL_BIND memory policy, if nodemask specifies
more than one node, page allocations will come from the node in the
nodemask with sufficient free memory that is closest to the home
node/preferred node.

For MPOL_PREFERRED_MANY if the nodemask specifies more than one node,
page allocation will come from the node in the nodemask with sufficient
free memory that is closest to the home node/preferred node.  If there
is not enough memory in all the nodes specified in the nodemask, the
allocation will be attempted from the closest numa node to the home node
in the system.

This helps applications to hint at a memory allocation preference node
and fallback to _only_ a set of nodes if the memory is not available on
the preferred node.  Fallback allocation is attempted from the node
which is nearest to the preferred node.

This helps applications to have control on memory allocation numa nodes
and avoids default fallback to slow memory NUMA nodes.  For example a
system with NUMA nodes 1,2 and 3 with DRAM memory and 10, 11 and 12 of
slow memory

 new_nodes = numa_bitmask_alloc(nr_nodes);

 numa_bitmask_setbit(new_nodes, 1);
 numa_bitmask_setbit(new_nodes, 2);
 numa_bitmask_setbit(new_nodes, 3);

 p = mmap(NULL, nr_pages * page_size, protflag, mapflag, -1, 0);
 mbind(p, nr_pages * page_size, MPOL_BIND, new_nodes->maskp,  new_nodes->size + 1, 0);

 sys_set_mempolicy_home_node(p, nr_pages * page_size, 2, 0);

This will allocate from nodes closer to node 2 and will make sure the
kernel will only allocate from nodes 1, 2, and 3.  Memory will not be
allocated from slow memory nodes 10, 11, and 12.  This differs from
default MPOL_BIND behavior in that with default MPOL_BIND the allocation
will be attempted from node closer to the local node.  One of the
reasons to specify a home node is to allow allocations from cpu less
NUMA node and its nearby NUMA nodes.

With MPOL_PREFERRED_MANY on the other hand will first try to allocate
from the closest node to node 2 from the node list 1, 2 and 3.  If those
nodes don't have enough memory, kernel will allocate from slow memory
node 10, 11 and 12 which ever is closer to node 2.

Link: https://lkml.kernel.org/r/20211202123810.267175-3-aneesh.kumar@linux.ibm.com


Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For hugetlb backed jobs/VMs it's critical to understand the numa
information for the memory backing these jobs to deliver optimal
performance.

Currently this technically can be queried from /proc/self/numa_maps, but
there are significant issues with that.  Namely:

1. Memory can be mapped or unmapped.

2. numa_maps are per process and need to be aggregated across all
   processes in the cgroup.  For shared memory this is more involved as
   the userspace needs to make sure it doesn't double count shared
   mappings.

3. I believe querying numa_maps needs to hold the mmap_lock which adds
   to the contention on this lock.

For these reasons I propose simply adding hugetlb.*.numa_stat file,
   which shows the numa information of the cgroup similarly to
   memory.numa_stat.

On cgroup-v2:
   cat /sys/fs/cgroup/unified/test/hugetlb.2MB.numa_stat
   total=2097152 N0=2097152 N1=0

On cgroup-v1:
   cat /sys/fs/cgroup/hugetlb/test/hugetlb.2MB.numa_stat
   total=2097152 N0=2097152 N1=0
   hierarichal_total=2097152 N0=2097152 N1=0

This patch was tested manually by allocating hugetlb memory and querying
the hugetlb.*.numa_stat file of the cgroup and its parents.

[colin.i.king@googlemail.com: fix spelling mistake "hierarichal" -> "hierarchical"]
  Link: https://lkml.kernel.org/r/20211125090635.23508-1-colin.i.king@gmail.com
[keescook@chromium.org: fix copy/paste array assignment]
  Link: https://lkml.kernel.org/r/20211203065647.2819707-1-keescook@chromium.org

Link: https://lkml.kernel.org/r/20211123001020.4083653-1-almasrymina@google.com


Signed-off-by: Mina Almasry <almasrymina@google.com>
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jue Wang <juew@google.com>
Cc: Yang Yao <ygyao@google.com>
Cc: Joanna Li <joannali@google.com>
Cc: Cannon Matthews <cannonmatthews@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For embedded systems with low total memory, having to run applications
with relatively large memory requirements, 10% max limitation for
watermark_scale_factor poses an issue of triggering direct reclaim every
time such application is started.  This results in slow application
startup times and bad end-user experience.

By increasing watermark_scale_factor max limit we allow vendors more
flexibility to choose the right level of kswapd aggressiveness for their
device and workload requirements.

Link: https://lkml.kernel.org/r/20211124193604.2758863-1-surenb@google.com


Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Zhang Yi <yi.zhang@huawei.com>
Cc: Fengfei Xi <xi.fengfei@h3c.com>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Check user page table entries at the time they are added and removed.

Allows to synchronously catch memory corruption issues related to double
mapping.

When a pte for an anonymous page is added into page table, we verify
that this pte does not already point to a file backed page, and vice
versa if this is a file backed page that is being added we verify that
this page does not have an anonymous mapping

We also enforce that read-only sharing for anonymous pages is allowed
(i.e.  cow after fork).  All other sharing must be for file pages.

Page table check allows to protect and debug cases where "struct page"
metadata became corrupted for some reason.  For example, when refcnt or
mapcount become invalid.

Link: https://lkml.kernel.org/r/20211221154650.1047963-4-pasha.tatashin@soleen.com


Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Xu <weixugc@google.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We have ptep_get_and_clear() and ptep_get_and_clear_full() helpers to
clear PTE from user page tables, but there is no variant for simple
clear of a present PTE from user page tables without using a low level
pte_clear() which can be either native or para-virtualised.

Add a new ptep_clear() that can be used in common code to clear PTEs
from page table.  We will need this call later in order to add a hook
for page table check.

Link: https://lkml.kernel.org/r/20211221154650.1047963-3-pasha.tatashin@soleen.com


Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Xu <weixugc@google.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add a new document to explain Virtually Mapped Kernel Stack Support.
This is a compilation of information from the code and original patch
series that introduced the Virtually Mapped Kernel Stacks feature.

This document summarizes the feature and provides details on allocation,
free, and stack overflow handling.  Provides reference to available
tests.

Link: https://lkml.kernel.org/r/20211215002004.47981-1-skhan@linuxfoundation.org


Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>