vdso: Introduce vdso/cache.h

The vDSO implementation can only include headers from the vdso/
namespace. To enable the usage of ____cacheline_aligned from
the vDSO, move it and its dependencies into

vdso: Introduce vdso/cache.h

The vDSO implementation can only include headers from the vdso/
namespace. To enable the usage of ____cacheline_aligned from
the vDSO, move it and its dependencies into a new header vdso/cache.h.
Keep compatibility by including vdso/cache.h from linux/cache.h.

Signed-off-by: Thomas Weißschuh <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/[email protected]

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cache: add __cacheline_group_{begin, end}_aligned() (+ couple more)

__cacheline_group_begin(), unfortunately, doesn't align the group
anyhow. If it is wanted, then you need to do something like

__c

cache: add __cacheline_group_{begin, end}_aligned() (+ couple more)

__cacheline_group_begin(), unfortunately, doesn't align the group
anyhow. If it is wanted, then you need to do something like

__cacheline_group_begin(grp) __aligned(ALIGN)

which isn't really convenient nor compact.
Add the _aligned() counterparts to align the groups automatically to
either the specified alignment (optional) or ``SMP_CACHE_BYTES``.
Note that the actual struct layout will then be (on x64 with 64-byte CL):

struct x {
u32 y; // offset 0, size 4, padding 56
__cacheline_group_begin__grp; // offset 64, size 0
u32 z; // offset 64, size 4, padding 4
__cacheline_group_end__grp; // offset 72, size 0
__cacheline_group_pad__grp; // offset 72, size 0, padding 56
u32 w; // offset 128
};

The end marker is aligned to long, so that you can assert the struct
size more strictly, but the offset of the next field in the structure
will be aligned to the group alignment, so that the next field won't
fall into the group it's not intended to.

Add __LARGEST_ALIGN definition and LARGEST_ALIGN() macro.
__LARGEST_ALIGN is the value to which the compilers align fields when
__aligned_largest is specified. Sometimes, it might be needed to get
this value outside of variable definitions. LARGEST_ALIGN() is macro
which just aligns a value to __LARGEST_ALIGN.
Also add SMP_CACHE_ALIGN(), similar to L1_CACHE_ALIGN(), but using
``SMP_CACHE_BYTES`` instead of ``L1_CACHE_BYTES`` as the former
also accounts L2, needed in some cases.

Signed-off-by: Alexander Lobakin <[email protected]>
Reviewed-by: Przemek Kitszel <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

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cache: enforce cache groups

Set up build time warnings to safeguard against future header changes of
organized structs.

Warning includes:

1) whether all variables are still in the same cache group

cache: enforce cache groups

Set up build time warnings to safeguard against future header changes of
organized structs.

Warning includes:

1) whether all variables are still in the same cache group
2) whether all the cache groups have the sum of the members size (in the
maximum condition, including all members defined in configs)

The __cache_group* variables are ignored in kernel-doc check in the
various header files they appear in to enforce the cache groups.

Suggested-by: Daniel Borkmann <[email protected]>
Acked-by: Daniel Borkmann <[email protected]>
Signed-off-by: Coco Li <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

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mm/slab: decouple ARCH_KMALLOC_MINALIGN from ARCH_DMA_MINALIGN

Patch series "mm, dma, arm64: Reduce ARCH_KMALLOC_MINALIGN to 8", v7.

A series reducing the kmalloc() minimum alignment on arm64 to 8

mm/slab: decouple ARCH_KMALLOC_MINALIGN from ARCH_DMA_MINALIGN

Patch series "mm, dma, arm64: Reduce ARCH_KMALLOC_MINALIGN to 8", v7.

A series reducing the kmalloc() minimum alignment on arm64 to 8 (from
128).


This patch (of 17):

In preparation for supporting a kmalloc() minimum alignment smaller than
the arch DMA alignment, decouple the two definitions. This requires that
either the kmalloc() caches are aligned to a (run-time) cache-line size or
the DMA API bounces unaligned kmalloc() allocations. Subsequent patches
will implement both options.

After this patch, ARCH_DMA_MINALIGN is expected to be used in static
alignment annotations and defined by an architecture to be the maximum
alignment for all supported configurations/SoCs in a single Image.
Architectures opting in to a smaller ARCH_KMALLOC_MINALIGN will need to
define its value in the arch headers.

Since ARCH_DMA_MINALIGN is now always defined, adjust the #ifdef in
dma_get_cache_alignment() so that there is no change for architectures not
requiring a minimum DMA alignment.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Catalin Marinas <[email protected]>
Tested-by: Isaac J. Manjarres <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Robin Murphy <[email protected]>
Cc: Alasdair Kergon <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Jonathan Cameron <[email protected]>
Cc: Marc Zyngier <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Mike Snitzer <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Saravana Kannan <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jerry Snitselaar <[email protected]>
Cc: Jonathan Cameron <[email protected]>
Cc: Lars-Peter Clausen <[email protected]>
Cc: Logan Gunthorpe <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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mm: deduplicate cacheline padding code

There are three users (mmzone.h, memcontrol.h, page_counter.h) using
similar code for forcing cacheline padding between fields of different
structures. Dedup

mm: deduplicate cacheline padding code

There are three users (mmzone.h, memcontrol.h, page_counter.h) using
similar code for forcing cacheline padding between fields of different
structures. Dedup that code.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Shakeel Butt <[email protected]>
Suggested-by: Feng Tang <[email protected]>
Reviewed-by: Feng Tang <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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treewide: Convert macro and uses of __section(foo) to __section("foo")

Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the q

treewide: Convert macro and uses of __section(foo) to __section("foo")

Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

https://lore.kernel.org/lkml/[email protected]/2-convert_section.pl

Signed-off-by: Joe Perches <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Reviewed-by: Miguel Ojeda <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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include/linux/cache.h: expand documentation over __read_mostly

__read_mostly can easily be misused by folks, its not meant for just
read-only data. There are performance reasons for using it, but w

include/linux/cache.h: expand documentation over __read_mostly

__read_mostly can easily be misused by folks, its not meant for just
read-only data. There are performance reasons for using it, but we also
don't provide any guidance about its use. Provide a bit more guidance
over its use.

Signed-off-by: Luis Chamberlain <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Acked-by: Christoph Lameter <[email protected]>
Acked-by: Rafael Aquini <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Philippe Ombredanne <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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arch: Introduce post-init read-only memory

One of the easiest ways to protect the kernel from attack is to reduce
the internal attack surface exposed when a "write" flaw is available. By
making as m

arch: Introduce post-init read-only memory

One of the easiest ways to protect the kernel from attack is to reduce
the internal attack surface exposed when a "write" flaw is available. By
making as much of the kernel read-only as possible, we reduce the
attack surface.

Many things are written to only during __init, and never changed
again. These cannot be made "const" since the compiler will do the wrong
thing (we do actually need to write to them). Instead, move these items
into a memory region that will be made read-only during mark_rodata_ro()
which happens after all kernel __init code has finished.

This introduces __ro_after_init as a way to mark such memory, and adds
some documentation about the existing __read_mostly marking.

This improves the security of the Linux kernel by marking formerly
read-write memory regions as read-only on a fully booted up system.

Based on work by PaX Team and Brad Spengler.

Signed-off-by: Kees Cook <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Brad Spengler <[email protected]>
Cc: Brian Gerst <[email protected]>
Cc: David Brown <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Emese Revfy <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mathias Krause <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: PaX Team <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: linux-arch <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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printk/cache: mark printk_once test variable __read_mostly

Add #include <linux/cache.h> to define __read_mostly.

Convert cache.h to use uapi/linux/kernel.h instead
of linux/kernel.h to avoid recurs

printk/cache: mark printk_once test variable __read_mostly

Add #include <linux/cache.h> to define __read_mostly.

Convert cache.h to use uapi/linux/kernel.h instead
of linux/kernel.h to avoid recursive #includes.

Convert the ALIGN macro to __ALIGN_KERNEL.

printk_once only sets the bool variable tested
once so mark it __read_mostly.

Neaten the alignment so it matches the rest of the
pr_<level>_once #defines too.

Signed-off-by: Joe Perches <[email protected]>
Reviewed-by: James Hogan <[email protected]>
Cc: Wu Fengguang <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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Rename .data.cacheline_aligned to .data..cacheline_aligned.

Signed-off-by: Tim Abbott <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Signed-off-by: Denys Vlasenko <[email protected]

Rename .data.cacheline_aligned to .data..cacheline_aligned.

Signed-off-by: Tim Abbott <[email protected]>
Cc: Sam Ravnborg <[email protected]>
Signed-off-by: Denys Vlasenko <[email protected]>
Signed-off-by: Michal Marek <[email protected]>

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mm: move cache_line_size() to <linux/cache.h>

Not all architectures define cache_line_size() so as suggested by Andrew move
the private implementations in mm/slab.c and mm/slob.c to <linux/cache.h>.

mm: move cache_line_size() to <linux/cache.h>

Not all architectures define cache_line_size() so as suggested by Andrew move
the private implementations in mm/slab.c and mm/slob.c to <linux/cache.h>.

Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Reviewed-by: Christoph Lameter <[email protected]>
Signed-off-by: Pekka Enberg <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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Don't include linux/config.h from anywhere else in include/

Signed-off-by: David Woodhouse <[email protected]>

[PATCH] Move read_mostly definition to asm/cache.h

Seems like needless clutter having a bunch of #if defined(CONFIG_$ARCH) in
include/linux/cache.h. Move the per architecture section definition to

[PATCH] Move read_mostly definition to asm/cache.h

Seems like needless clutter having a bunch of #if defined(CONFIG_$ARCH) in
include/linux/cache.h. Move the per architecture section definition to
asm/cache.h, and keep the if-not-defined dummy case in linux/cache.h to
catch architectures which don't implement the section.

Verified that symbols still go in .data.read_mostly on parisc,
and the compile doesn't break.

Signed-off-by: Kyle McMartin <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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[PARISC] Add __read_mostly section for parisc

Flag a whole bunch of things as __read_mostly on parisc. Also flag a few
branches as unlikely() and cleanup a bit of code.

Signed-off-by: Helge Deller

[PARISC] Add __read_mostly section for parisc

Flag a whole bunch of things as __read_mostly on parisc. Also flag a few
branches as unlikely() and cleanup a bit of code.

Signed-off-by: Helge Deller <[email protected]>
Signed-off-by: Kyle McMartin <[email protected]>

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[PATCH] Change maxaligned_in_smp alignemnt macros to internodealigned_in_smp macros

____cacheline_maxaligned_in_smp is currently used to align critical structures
and avoid false sharing. It uses p

[PATCH] Change maxaligned_in_smp alignemnt macros to internodealigned_in_smp macros

____cacheline_maxaligned_in_smp is currently used to align critical structures
and avoid false sharing. It uses per-arch L1_CACHE_SHIFT_MAX and people find
L1_CACHE_SHIFT_MAX useless.

However, we have been using ____cacheline_maxaligned_in_smp to align
structures on the internode cacheline size. As per Andi's suggestion,
following patch kills ____cacheline_maxaligned_in_smp and introduces
INTERNODE_CACHE_SHIFT, which defaults to L1_CACHE_SHIFT for all arches.
Arches needing L3/Internode cacheline alignment can define
INTERNODE_CACHE_SHIFT in the arch asm/cache.h. Patch replaces
____cacheline_maxaligned_in_smp with ____cacheline_internodealigned_in_smp

With this patch, L1_CACHE_SHIFT_MAX can be killed

Signed-off-by: Ravikiran Thirumalai <[email protected]>
Signed-off-by: Shai Fultheim <[email protected]>
Signed-off-by: Andi Kleen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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[IA64] Add __read_mostly support for IA64

sparc64, i386 and x86_64 have support for a special data section dedicated
to rarely updated data that is frequently read. The section was created to
avoid

[IA64] Add __read_mostly support for IA64

sparc64, i386 and x86_64 have support for a special data section dedicated
to rarely updated data that is frequently read. The section was created to
avoid false sharing of those rarely read data with frequently written kernel
data.

This patch creates such a data section for ia64 and will group rarely written
data into this section.

Signed-off-by: Christoph Lameter <[email protected]>
Signed-off-by: Tony Luck <[email protected]>

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[SPARC64]: Add __read_mostly support.

Signed-off-by: David S. Miller <[email protected]>

[PATCH] mostly_read data section

Add a new section called ".data.read_mostly" for data items that are read
frequently and rarely written to like cpumaps etc.

If these maps are placed in the .data s

[PATCH] mostly_read data section

Add a new section called ".data.read_mostly" for data items that are read
frequently and rarely written to like cpumaps etc.

If these maps are placed in the .data section then these frequenly read
items may end up in cachelines with data is is frequently updated. In that
case all processors in an SMP system must needlessly reload the cachelines
again and again containing elements of those frequently used variables.

The ability to share these cachelines will allow each cpu in an SMP system
to keep local copies of those shared cachelines thereby optimizing
performance.

Signed-off-by: Alok N Kataria <[email protected]>
Signed-off-by: Shobhit Dayal <[email protected]>
Signed-off-by: Christoph Lameter <[email protected]>
Signed-off-by: Shai Fultheim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

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Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

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