linux.git/arch/x86/Kconfig.debug, branch v5.6

x86: mm: convert dump_pagetables to use walk_page_range

2020-02-04T03:05:25+00:00

Make use of the new functionality in walk_page_range to remove the arch
page walking code and use the generic code to walk the page tables.

The effective permissions are passed down the chain using new fields in
struct pg_state.

The KASAN optimisation is implemented by setting action=CONTINUE in the
callbacks to skip an entire tree of entries.

Link: http://lkml.kernel.org/r/20191218162402.45610-21-steven.price@arm.com
Signed-off-by: Steven Price 
Cc: Albert Ou 
Cc: Alexandre Ghiti 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Borislav Petkov 
Cc: Catalin Marinas 
Cc: Christian Borntraeger 
Cc: Dave Hansen 
Cc: David S. Miller 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: James Hogan 
Cc: James Morse 
Cc: Jerome Glisse 
Cc: "Liang, Kan" 
Cc: Mark Rutland 
Cc: Michael Ellerman 
Cc: Paul Burton 
Cc: Paul Mackerras 
Cc: Paul Walmsley 
Cc: Peter Zijlstra 
Cc: Ralf Baechle 
Cc: Russell King 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Will Deacon 
Cc: Zong Li 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

x86/traps: Disentangle the 32-bit and 64-bit doublefault code

2019-11-26T20:53:34+00:00

The 64-bit doublefault handler is much nicer than the 32-bit one.
As a first step toward unifying them, make the 64-bit handler
self-contained.  This should have no effect no functional effect
except in the odd case of x86_64 with CONFIG_DOUBLEFAULT=n in which
case it will change the logging a bit.

This also gets rid of CONFIG_DOUBLEFAULT configurability on 64-bit
kernels.  It didn't do anything useful -- CONFIG_DOUBLEFAULT=n
didn't actually disable doublefault handling on x86_64.

Signed-off-by: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Linus Torvalds 
Signed-off-by: Ingo Molnar

x86/stacktrace: update kconfig help text for reliable unwinders

2019-11-07T14:48:18+00:00

commit 6415b38bae26 ("x86/stacktrace: Enable HAVE_RELIABLE_STACKTRACE
for the ORC unwinder") added the ORC unwinder as a "reliable" unwinder.
Update the help text to reflect that change: the frame pointer unwinder
is no longer the only one that can provide HAVE_RELIABLE_STACKTRACE.

Link: http://lkml.kernel.org/r/20191107032958.14034-1-joe.lawrence@redhat.com
To: linux-kernel@vger.kernel.org
To: live-patching@vger.kernel.org
Signed-off-by: Joe Lawrence 
Acked-by: Josh Poimboeuf 
Acked-by: Miroslav Benes 
Reviewed-by: Kamalesh Babulal 
Signed-off-by: Petr Mladek

x86, perf: Fix the dependency of the x86 insn decoder selftest

2019-09-02T18:05:58+00:00

Since x86 instruction decoder is not only for kprobes,
it should be tested when the insn.c is compiled.
(e.g. perf is enabled but kprobes is disabled)

Signed-off-by: Masami Hiramatsu 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Fixes: cbe5c34c8c1f ("x86: Compile insn.c and inat.c only for KPROBES")
Signed-off-by: Ingo Molnar

Merge tag 'docs-5.3' of git://git.lwn.net/linux

2019-07-09T19:34:26+00:00

Pull Documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle for docs:

   - A fair pile of RST conversions, many from Mauro. These create more
     than the usual number of simple but annoying merge conflicts with
     other trees, unfortunately. He has a lot more of these waiting on
     the wings that, I think, will go to you directly later on.

   - A new document on how to use merges and rebases in kernel repos,
     and one on Spectre vulnerabilities.

   - Various improvements to the build system, including automatic
     markup of function() references because some people, for reasons I
     will never understand, were of the opinion that
     :c:func:``function()`` is unattractive and not fun to type.

   - We now recommend using sphinx 1.7, but still support back to 1.4.

   - Lots of smaller improvements, warning fixes, typo fixes, etc"

* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
  docs: automarkup.py: ignore exceptions when seeking for xrefs
  docs: Move binderfs to admin-guide
  Disable Sphinx SmartyPants in HTML output
  doc: RCU callback locks need only _bh, not necessarily _irq
  docs: format kernel-parameters -- as code
  Doc : doc-guide : Fix a typo
  platform: x86: get rid of a non-existent document
  Add the RCU docs to the core-api manual
  Documentation: RCU: Add TOC tree hooks
  Documentation: RCU: Rename txt files to rst
  Documentation: RCU: Convert RCU UP systems to reST
  Documentation: RCU: Convert RCU linked list to reST
  Documentation: RCU: Convert RCU basic concepts to reST
  docs: filesystems: Remove uneeded .rst extension on toctables
  scripts/sphinx-pre-install: fix out-of-tree build
  docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
  Documentation: PGP: update for newer HW devices
  Documentation: Add section about CPU vulnerabilities for Spectre
  Documentation: platform: Delete x86-laptop-drivers.txt
  docs: Note that :c:func: should no longer be used
  ...

docs: fix broken documentation links

2019-06-08T19:42:13+00:00

Mostly due to x86 and acpi conversion, several documentation
links are still pointing to the old file. Fix them.

Signed-off-by: Mauro Carvalho Chehab 
Reviewed-by: Wolfram Sang 
Reviewed-by: Sven Van Asbroeck 
Reviewed-by: Bhupesh Sharma 
Acked-by: Mark Brown 
Signed-off-by: Jonathan Corbet

x86/io_delay: Define IO_DELAY macros in C instead of Kconfig

2019-05-24T06:46:06+00:00

CONFIG_IO_DELAY_TYPE_* are not kernel configuration at all. They just
define constant values, 0, 1, 2, and 3. Define them by #define in C.

CONFIG_DEFAULT_IO_DELAY_TYPE can also be defined in C by using #ifdef
and #define directives.

Signed-off-by: Masahiro Yamada 
Cc: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20190521072211.21014-2-yamada.masahiro@socionext.com
Signed-off-by: Ingo Molnar

compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING

2019-05-15T02:52:48+00:00

Commit 60a3cdd06394 ("x86: add optimized inlining") introduced
CONFIG_OPTIMIZE_INLINING, but it has been available only for x86.

The idea is obviously arch-agnostic.  This commit moves the config entry
from arch/x86/Kconfig.debug to lib/Kconfig.debug so that all
architectures can benefit from it.

This can make a huge difference in kernel image size especially when
CONFIG_OPTIMIZE_FOR_SIZE is enabled.

For example, I got 3.5% smaller arm64 kernel for v5.1-rc1.

  dec       file
  18983424  arch/arm64/boot/Image.before
  18321920  arch/arm64/boot/Image.after

This also slightly improves the "Kernel hacking" Kconfig menu as
e61aca5158a8 ("Merge branch 'kconfig-diet' from Dave Hansen') suggested;
this config option would be a good fit in the "compiler option" menu.

Link: http://lkml.kernel.org/r/20190423034959.13525-12-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada 
Acked-by: Borislav Petkov 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Boris Brezillon 
Cc: Brian Norris 
Cc: Christophe Leroy 
Cc: David Woodhouse 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Ingo Molnar 
Cc: Marek Vasut 
Cc: Mark Rutland 
Cc: Mathieu Malaterre 
Cc: Miquel Raynal 
Cc: Paul Mackerras 
Cc: Ralf Baechle 
Cc: Richard Weinberger 
Cc: Russell King 
Cc: Stefan Agner 
Cc: Thomas Gleixner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

efi/x86: Convert x86 EFI earlyprintk into generic earlycon implementation

2019-02-04T07:27:30+00:00

Move the x86 EFI earlyprintk implementation to a shared location under
drivers/firmware and tweak it slightly so we can expose it as an earlycon
implementation (which is generic) rather than earlyprintk (which is only
implemented for a few architectures)

This also involves switching to write-combine mappings by default (which
is required on ARM since device mappings lack memory semantics, and so
memcpy/memset may not be used on them), and adding support for shared
memory framebuffers on cache coherent non-x86 systems (which do not
tolerate mismatched attributes).

Note that 32-bit ARM does not populate its struct screen_info early
enough for earlycon=efifb to work, so it is disabled there.

Signed-off-by: Ard Biesheuvel 
Reviewed-by: Alexander Graf 
Cc: AKASHI Takahiro 
Cc: Bjorn Andersson 
Cc: Borislav Petkov 
Cc: Heinrich Schuchardt 
Cc: Jeffrey Hugo 
Cc: Lee Jones 
Cc: Leif Lindholm 
Cc: Linus Torvalds 
Cc: Matt Fleming 
Cc: Peter Jones 
Cc: Peter Zijlstra 
Cc: Sai Praneeth Prakhya 
Cc: Thomas Gleixner 
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190202094119.13230-10-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar

x86/kconfig: Remove redundant 'default n' lines from all x86 Kconfig's

2018-10-17T06:39:42+00:00

'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.

Also, since commit:

  f467c5640c29 ("kconfig: only write '# CONFIG_FOO is not set' for visible symbols")

... the Kconfig behavior is the same regardless of 'default n' being present or not:

    ...
    One side effect of (and the main motivation for) this change is making
    the following two definitions behave exactly the same:

        config FOO
                bool

        config FOO
                bool
                default n

    With this change, neither of these will generate a
    '# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
    That might make it clearer to people that a bare 'default n' is
    redundant.
    ...

Signed-off-by: Bartlomiej Zolnierkiewicz 
Cc: Boris Ostrovsky 
Cc: Borislav Petkov 
Cc: Juergen Gross 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20181016134217eucas1p2102984488b89178a865162553369025b%7EeGpI5NlJo0851008510eucas1p2D@eucas1p2.samsung.com
Signed-off-by: Ingo Molnar