<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/init/Kconfig, branch v6.6.14</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.14</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.14'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2023-08-29T21:53:51+00:00</updated>
<entry>
<title>Merge tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm</title>
<updated>2023-08-29T21:53:51+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-08-29T21:53:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=d68b4b6f307d155475cce541f2aee938032ed22e'/>
<id>urn:sha1:d68b4b6f307d155475cce541f2aee938032ed22e</id>
<content type='text'>
Pull non-MM updates from Andrew Morton:

 - An extensive rework of kexec and crash Kconfig from Eric DeVolder
   ("refactor Kconfig to consolidate KEXEC and CRASH options")

 - kernel.h slimming work from Andy Shevchenko ("kernel.h: Split out a
   couple of macros to args.h")

 - gdb feature work from Kuan-Ying Lee ("Add GDB memory helper
   commands")

 - vsprintf inclusion rationalization from Andy Shevchenko
   ("lib/vsprintf: Rework header inclusions")

 - Switch the handling of kdump from a udev scheme to in-kernel
   handling, by Eric DeVolder ("crash: Kernel handling of CPU and memory
   hot un/plug")

 - Many singleton patches to various parts of the tree

* tag 'mm-nonmm-stable-2023-08-28-22-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (81 commits)
  document while_each_thread(), change first_tid() to use for_each_thread()
  drivers/char/mem.c: shrink character device's devlist[] array
  x86/crash: optimize CPU changes
  crash: change crash_prepare_elf64_headers() to for_each_possible_cpu()
  crash: hotplug support for kexec_load()
  x86/crash: add x86 crash hotplug support
  crash: memory and CPU hotplug sysfs attributes
  kexec: exclude elfcorehdr from the segment digest
  crash: add generic infrastructure for crash hotplug support
  crash: move a few code bits to setup support of crash hotplug
  kstrtox: consistently use _tolower()
  kill do_each_thread()
  nilfs2: fix WARNING in mark_buffer_dirty due to discarded buffer reuse
  scripts/bloat-o-meter: count weak symbol sizes
  treewide: drop CONFIG_EMBEDDED
  lockdep: fix static memory detection even more
  lib/vsprintf: declare no_hash_pointers in sprintf.h
  lib/vsprintf: split out sprintf() and friends
  kernel/fork: stop playing lockless games for exe_file replacement
  adfs: delete unused "union adfs_dirtail" definition
  ...
</content>
</entry>
<entry>
<title>treewide: drop CONFIG_EMBEDDED</title>
<updated>2023-08-21T20:46:25+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2023-08-16T05:50:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=ef815d2cba782e96b9aad9483523d474ed41c62a'/>
<id>urn:sha1:ef815d2cba782e96b9aad9483523d474ed41c62a</id>
<content type='text'>
There is only one Kconfig user of CONFIG_EMBEDDED and it can be switched
to EXPERT or "if !ARCH_MULTIPLATFORM" (suggested by Arnd).

Link: https://lkml.kernel.org/r/20230816055010.31534-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Acked-by: Geert Uytterhoeven &lt;geert+renesas@glider.be&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Palmer Dabbelt &lt;palmer@rivosinc.com&gt;	[RISC-V]
Acked-by: Greg Ungerer &lt;gerg@linux-m68k.org&gt;
Acked-by: Jason A. Donenfeld &lt;Jason@zx2c4.com&gt;
Acked-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;	[powerpc]
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Vineet Gupta &lt;vgupta@kernel.org&gt;
Cc: Brian Cain &lt;bcain@quicinc.com&gt;
Cc: Michal Simek &lt;monstr@monstr.eu&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Dinh Nguyen &lt;dinguyen@kernel.org&gt;
Cc: Jonas Bonn &lt;jonas@southpole.se&gt;
Cc: Stefan Kristiansson &lt;stefan.kristiansson@saunalahti.fi&gt;
Cc: Stafford Horne &lt;shorne@gmail.com&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Max Filippov &lt;jcmvbkbc@gmail.com&gt;
Cc: Josh Triplett &lt;josh@joshtriplett.org&gt;
Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>kexec: consolidate kexec and crash options into kernel/Kconfig.kexec</title>
<updated>2023-08-18T17:18:51+00:00</updated>
<author>
<name>Eric DeVolder</name>
<email>eric.devolder@oracle.com</email>
</author>
<published>2023-07-12T16:15:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=89cde455915f4611aa5dcf7d0286d88b48914b00'/>
<id>urn:sha1:89cde455915f4611aa5dcf7d0286d88b48914b00</id>
<content type='text'>
Patch series "refactor Kconfig to consolidate KEXEC and CRASH options", v6.

The Kconfig is refactored to consolidate KEXEC and CRASH options from
various arch/&lt;arch&gt;/Kconfig files into new file kernel/Kconfig.kexec.

The Kconfig.kexec is now a submenu titled "Kexec and crash features"
located under "General Setup".

The following options are impacted:

 - KEXEC
 - KEXEC_FILE
 - KEXEC_SIG
 - KEXEC_SIG_FORCE
 - KEXEC_IMAGE_VERIFY_SIG
 - KEXEC_BZIMAGE_VERIFY_SIG
 - KEXEC_JUMP
 - CRASH_DUMP

Over time, these options have been copied between Kconfig files and
are very similar to one another, but with slight differences.

The following architectures are impacted by the refactor (because of
use of one or more KEXEC/CRASH options):

 - arm
 - arm64
 - ia64
 - loongarch
 - m68k
 - mips
 - parisc
 - powerpc
 - riscv
 - s390
 - sh
 - x86 

More information:

In the patch series "crash: Kernel handling of CPU and memory hot
un/plug"

 https://lore.kernel.org/lkml/20230503224145.7405-1-eric.devolder@oracle.com/

the new kernel feature introduces the config option CRASH_HOTPLUG.

In reviewing, Thomas Gleixner requested that the new config option
not be placed in x86 Kconfig. Rather the option needs a generic/common
home. To Thomas' point, the KEXEC and CRASH options have largely been
duplicated in the various arch/&lt;arch&gt;/Kconfig files, with minor
differences. This kind of proliferation is to be avoid/stopped.

 https://lore.kernel.org/lkml/875y91yv63.ffs@tglx/

To that end, I have refactored the arch Kconfigs so as to consolidate
the various KEXEC and CRASH options. Generally speaking, this work has
the following themes:

- KEXEC and CRASH options are moved into new file kernel/Kconfig.kexec
  - These items from arch/Kconfig:
      CRASH_CORE KEXEC_CORE KEXEC_ELF HAVE_IMA_KEXEC
  - These items from arch/x86/Kconfig form the common options:
      KEXEC KEXEC_FILE KEXEC_SIG KEXEC_SIG_FORCE
      KEXEC_BZIMAGE_VERIFY_SIG KEXEC_JUMP CRASH_DUMP
  - These items from arch/arm64/Kconfig form the common options:
      KEXEC_IMAGE_VERIFY_SIG
  - The crash hotplug series appends CRASH_HOTPLUG to Kconfig.kexec
- The Kconfig.kexec is now a submenu titled "Kexec and crash features"
  and is now listed in "General Setup" submenu from init/Kconfig.
- To control the common options, each has a new ARCH_SUPPORTS_&lt;option&gt;
  option. These gateway options determine whether the common options
  options are valid for the architecture.
- To account for the slight differences in the original architecture
  coding of the common options, each now has a corresponding
  ARCH_SELECTS_&lt;option&gt; which are used to elicit the same side effects
  as the original arch/&lt;arch&gt;/Kconfig files for KEXEC and CRASH options.

An example, 'make menuconfig' illustrating the submenu:

  &gt; General setup &gt; Kexec and crash features
  [*] Enable kexec system call
  [*] Enable kexec file based system call
  [*]   Verify kernel signature during kexec_file_load() syscall
  [ ]     Require a valid signature in kexec_file_load() syscall
  [ ]     Enable bzImage signature verification support
  [*] kexec jump
  [*] kernel crash dumps
  [*]   Update the crash elfcorehdr on system configuration changes

In the process of consolidating the common options, I encountered
slight differences in the coding of these options in several of the
architectures. As a result, I settled on the following solution:

- Each of the common options has a 'depends on ARCH_SUPPORTS_&lt;option&gt;'
  statement. For example, the KEXEC_FILE option has a 'depends on
  ARCH_SUPPORTS_KEXEC_FILE' statement.

  This approach is needed on all common options so as to prevent
  options from appearing for architectures which previously did
  not allow/enable them. For example, arm supports KEXEC but not
  KEXEC_FILE. The arch/arm/Kconfig does not provide
  ARCH_SUPPORTS_KEXEC_FILE and so KEXEC_FILE and related options
  are not available to arm.

- The boolean ARCH_SUPPORTS_&lt;option&gt; in effect allows the arch to
  determine when the feature is allowed.  Archs which don't have the
  feature simply do not provide the corresponding ARCH_SUPPORTS_&lt;option&gt;.
  For each arch, where there previously were KEXEC and/or CRASH
  options, these have been replaced with the corresponding boolean
  ARCH_SUPPORTS_&lt;option&gt;, and an appropriate def_bool statement.

  For example, if the arch supports KEXEC_FILE, then the
  ARCH_SUPPORTS_KEXEC_FILE simply has a 'def_bool y'. This permits
  the KEXEC_FILE option to be available.

  If the arch has a 'depends on' statement in its original coding
  of the option, then that expression becomes part of the def_bool
  expression. For example, arm64 had:

  config KEXEC
    depends on PM_SLEEP_SMP

  and in this solution, this converts to:

  config ARCH_SUPPORTS_KEXEC
    def_bool PM_SLEEP_SMP


- In order to account for the architecture differences in the
  coding for the common options, the ARCH_SELECTS_&lt;option&gt; in the
  arch/&lt;arch&gt;/Kconfig is used. This option has a 'depends on
  &lt;option&gt;' statement to couple it to the main option, and from
  there can insert the differences from the common option and the
  arch original coding of that option.

  For example, a few archs enable CRYPTO and CRYTPO_SHA256 for
  KEXEC_FILE. These require a ARCH_SELECTS_KEXEC_FILE and
  'select CRYPTO' and 'select CRYPTO_SHA256' statements.

Illustrating the option relationships:

For each of the common KEXEC and CRASH options:
 ARCH_SUPPORTS_&lt;option&gt; &lt;- &lt;option&gt; &lt;- ARCH_SELECTS_&lt;option&gt;

 &lt;option&gt;                   # in Kconfig.kexec
 ARCH_SUPPORTS_&lt;option&gt;     # in arch/&lt;arch&gt;/Kconfig, as needed
 ARCH_SELECTS_&lt;option&gt;      # in arch/&lt;arch&gt;/Kconfig, as needed


For example, KEXEC:
 ARCH_SUPPORTS_KEXEC &lt;- KEXEC &lt;- ARCH_SELECTS_KEXEC

 KEXEC                      # in Kconfig.kexec
 ARCH_SUPPORTS_KEXEC        # in arch/&lt;arch&gt;/Kconfig, as needed
 ARCH_SELECTS_KEXEC         # in arch/&lt;arch&gt;/Kconfig, as needed


To summarize, the ARCH_SUPPORTS_&lt;option&gt; permits the &lt;option&gt; to be
enabled, and the ARCH_SELECTS_&lt;option&gt; handles side effects (ie.
select statements).

Examples:
A few examples to show the new strategy in action:

===== x86 (minus the help section) =====
Original:
 config KEXEC
    bool "kexec system call"
    select KEXEC_CORE

 config KEXEC_FILE
    bool "kexec file based system call"
    select KEXEC_CORE
    select HAVE_IMA_KEXEC if IMA
    depends on X86_64
    depends on CRYPTO=y
    depends on CRYPTO_SHA256=y

 config ARCH_HAS_KEXEC_PURGATORY
    def_bool KEXEC_FILE

 config KEXEC_SIG
    bool "Verify kernel signature during kexec_file_load() syscall"
    depends on KEXEC_FILE

 config KEXEC_SIG_FORCE
    bool "Require a valid signature in kexec_file_load() syscall"
    depends on KEXEC_SIG

 config KEXEC_BZIMAGE_VERIFY_SIG
    bool "Enable bzImage signature verification support"
    depends on KEXEC_SIG
    depends on SIGNED_PE_FILE_VERIFICATION
    select SYSTEM_TRUSTED_KEYRING

 config CRASH_DUMP
    bool "kernel crash dumps"
    depends on X86_64 || (X86_32 &amp;&amp; HIGHMEM)

 config KEXEC_JUMP
    bool "kexec jump"
    depends on KEXEC &amp;&amp; HIBERNATION
    help

becomes...
New:
config ARCH_SUPPORTS_KEXEC
    def_bool y

config ARCH_SUPPORTS_KEXEC_FILE
    def_bool X86_64 &amp;&amp; CRYPTO &amp;&amp; CRYPTO_SHA256

config ARCH_SELECTS_KEXEC_FILE
    def_bool y
    depends on KEXEC_FILE
    select HAVE_IMA_KEXEC if IMA

config ARCH_SUPPORTS_KEXEC_PURGATORY
    def_bool KEXEC_FILE

config ARCH_SUPPORTS_KEXEC_SIG
    def_bool y

config ARCH_SUPPORTS_KEXEC_SIG_FORCE
    def_bool y

config ARCH_SUPPORTS_KEXEC_BZIMAGE_VERIFY_SIG
    def_bool y

config ARCH_SUPPORTS_KEXEC_JUMP
    def_bool y

config ARCH_SUPPORTS_CRASH_DUMP
    def_bool X86_64 || (X86_32 &amp;&amp; HIGHMEM)


===== powerpc (minus the help section) =====
Original:
 config KEXEC
    bool "kexec system call"
    depends on PPC_BOOK3S || PPC_E500 || (44x &amp;&amp; !SMP)
    select KEXEC_CORE

 config KEXEC_FILE
    bool "kexec file based system call"
    select KEXEC_CORE
    select HAVE_IMA_KEXEC if IMA
    select KEXEC_ELF
    depends on PPC64
    depends on CRYPTO=y
    depends on CRYPTO_SHA256=y

 config ARCH_HAS_KEXEC_PURGATORY
    def_bool KEXEC_FILE

 config CRASH_DUMP
    bool "Build a dump capture kernel"
    depends on PPC64 || PPC_BOOK3S_32 || PPC_85xx || (44x &amp;&amp; !SMP)
    select RELOCATABLE if PPC64 || 44x || PPC_85xx

becomes...
New:
config ARCH_SUPPORTS_KEXEC
    def_bool PPC_BOOK3S || PPC_E500 || (44x &amp;&amp; !SMP)

config ARCH_SUPPORTS_KEXEC_FILE
    def_bool PPC64 &amp;&amp; CRYPTO=y &amp;&amp; CRYPTO_SHA256=y

config ARCH_SUPPORTS_KEXEC_PURGATORY
    def_bool KEXEC_FILE

config ARCH_SELECTS_KEXEC_FILE
    def_bool y
    depends on KEXEC_FILE
    select KEXEC_ELF
    select HAVE_IMA_KEXEC if IMA

config ARCH_SUPPORTS_CRASH_DUMP
    def_bool PPC64 || PPC_BOOK3S_32 || PPC_85xx || (44x &amp;&amp; !SMP)

config ARCH_SELECTS_CRASH_DUMP
    def_bool y
    depends on CRASH_DUMP
    select RELOCATABLE if PPC64 || 44x || PPC_85xx


Testing Approach and Results

There are 388 config files in the arch/&lt;arch&gt;/configs directories.
For each of these config files, a .config is generated both before and
after this Kconfig series, and checked for equivalence. This approach
allows for a rather rapid check of all architectures and a wide
variety of configs wrt/ KEXEC and CRASH, and avoids requiring
compiling for all architectures and running kernels and run-time
testing.

For each config file, the olddefconfig, allnoconfig and allyesconfig
targets are utilized. In testing the randconfig has revealed problems
as well, but is not used in the before and after equivalence check
since one can not generate the "same" .config for before and after,
even if using the same KCONFIG_SEED since the option list is
different.

As such, the following script steps compare the before and after
of 'make olddefconfig'. The new symbols introduced by this series
are filtered out, but otherwise the config files are PASS only if
they were equivalent, and FAIL otherwise.

The script performs the test by doing the following:

 # Obtain the "golden" .config output for given config file
 # Reset test sandbox
 git checkout master
 git branch -D test_Kconfig
 git checkout -B test_Kconfig master
 make distclean
 # Write out updated config
 cp -f &lt;config file&gt; .config
 make ARCH=&lt;arch&gt; olddefconfig
 # Track each item in .config, LHSB is "golden"
 scoreboard .config 

 # Obtain the "changed" .config output for given config file
 # Reset test sandbox
 make distclean
 # Apply this Kconfig series
 git am &lt;this Kconfig series&gt;
 # Write out updated config
 cp -f &lt;config file&gt; .config
 make ARCH=&lt;arch&gt; olddefconfig
 # Track each item in .config, RHSB is "changed"
 scoreboard .config 

 # Determine test result
 # Filter-out new symbols introduced by this series
 # Filter-out symbol=n which not in either scoreboard
 # Compare LHSB "golden" and RHSB "changed" scoreboards and issue PASS/FAIL

The script was instrumental during the refactoring of Kconfig as it
continually revealed problems. The end result being that the solution
presented in this series passes all configs as checked by the script,
with the following exceptions:

- arch/ia64/configs/zx1_config with olddefconfig
  This config file has:
  # CONFIG_KEXEC is not set
  CONFIG_CRASH_DUMP=y
  and this refactor now couples KEXEC to CRASH_DUMP, so it is not
  possible to enable CRASH_DUMP without KEXEC.

- arch/sh/configs/* with allyesconfig
  The arch/sh/Kconfig codes CRASH_DUMP as dependent upon BROKEN_ON_MMU
  (which clearly is not meant to be set). This symbol is not provided
  but with the allyesconfig it is set to yes which enables CRASH_DUMP.
  But KEXEC is coded as dependent upon MMU, and is set to no in
  arch/sh/mm/Kconfig, so KEXEC is not enabled.
  This refactor now couples KEXEC to CRASH_DUMP, so it is not
  possible to enable CRASH_DUMP without KEXEC.

While the above exceptions are not equivalent to their original,
the config file produced is valid (and in fact better wrt/ CRASH_DUMP
handling).


This patch (of 14)

The config options for kexec and crash features are consolidated
into new file kernel/Kconfig.kexec. Under the "General Setup" submenu
is a new submenu "Kexec and crash handling". All the kexec and
crash options that were once in the arch-dependent submenu "Processor
type and features" are now consolidated in the new submenu.

The following options are impacted:

 - KEXEC
 - KEXEC_FILE
 - KEXEC_SIG
 - KEXEC_SIG_FORCE
 - KEXEC_BZIMAGE_VERIFY_SIG
 - KEXEC_JUMP
 - CRASH_DUMP

The three main options are KEXEC, KEXEC_FILE and CRASH_DUMP.

Architectures specify support of certain KEXEC and CRASH features with
similarly named new ARCH_SUPPORTS_&lt;option&gt; config options.

Architectures can utilize the new ARCH_SELECTS_&lt;option&gt; config
options to specify additional components when &lt;option&gt; is enabled.

To summarize, the ARCH_SUPPORTS_&lt;option&gt; permits the &lt;option&gt; to be
enabled, and the ARCH_SELECTS_&lt;option&gt; handles side effects (ie.
select statements).

Link: https://lkml.kernel.org/r/20230712161545.87870-1-eric.devolder@oracle.com
Link: https://lkml.kernel.org/r/20230712161545.87870-2-eric.devolder@oracle.com
Signed-off-by: Eric DeVolder &lt;eric.devolder@oracle.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Anshuman Khandual &lt;anshuman.khandual@arm.com&gt;
Cc: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Baoquan He &lt;bhe@redhat.com&gt;
Cc: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Cc: Boris Ostrovsky &lt;boris.ostrovsky@oracle.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Cc. "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt; # for x86
Cc: Frederic Weisbecker &lt;frederic@kernel.org&gt;
Cc: Geert Uytterhoeven &lt;geert@linux-m68k.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Hari Bathini &lt;hbathini@linux.ibm.com&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Helge Deller &lt;deller@gmx.de&gt;
Cc: Huacai Chen &lt;chenhuacai@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: "James E.J. Bottomley" &lt;James.Bottomley@HansenPartnership.com&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Juerg Haefliger &lt;juerg.haefliger@canonical.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Konrad Rzeszutek Wilk &lt;konrad.wilk@oracle.com&gt;
Cc: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Cc: Marc Aurèle La France &lt;tsi@tuyoix.net&gt;
Cc: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Cc: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Miguel Ojeda &lt;ojeda@kernel.org&gt;
Cc: Mike Rapoport (IBM) &lt;rppt@kernel.org&gt;
Cc: Nicholas Piggin &lt;npiggin@gmail.com&gt;
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Paul E. McKenney &lt;paulmck@kernel.org&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Rich Felker &lt;dalias@libc.org&gt;
Cc: Russell King &lt;linux@armlinux.org.uk&gt;
Cc: Russell King (Oracle) &lt;rmk+kernel@armlinux.org.uk&gt;
Cc: Sami Tolvanen &lt;samitolvanen@google.com&gt;
Cc: Sebastian Reichel &lt;sebastian.reichel@collabora.com&gt;
Cc: Sourabh Jain &lt;sourabhjain@linux.ibm.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Tejun Heo &lt;tj@kernel.org&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: WANG Xuerui &lt;kernel@xen0n.name&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Xin Li &lt;xin3.li@intel.com&gt;
Cc: Yoshinori Sato &lt;ysato@users.sourceforge.jp&gt;
Cc: Zhen Lei &lt;thunder.leizhen@huawei.com&gt;
Cc: Zi Yan &lt;ziy@nvidia.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>sched/psi: Select KERNFS as needed</title>
<updated>2023-08-02T14:19:25+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2023-07-31T03:07:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=98dfdd9ee93995a408192dbbf3dd219ba23e3738'/>
<id>urn:sha1:98dfdd9ee93995a408192dbbf3dd219ba23e3738</id>
<content type='text'>
Users of KERNFS should select it to enforce its being built, so
do this to prevent a build error.

In file included from ../kernel/sched/build_utility.c:97:
../kernel/sched/psi.c: In function 'psi_trigger_poll':
../kernel/sched/psi.c:1479:17: error: implicit declaration of function 'kernfs_generic_poll' [-Werror=implicit-function-declaration]
 1479 |                 kernfs_generic_poll(t-&gt;of, wait);

Fixes: aff037078eca ("sched/psi: use kernfs polling functions for PSI trigger polling")
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Suren Baghdasaryan &lt;surenb@google.com&gt;
Link: lore.kernel.org/r/202307310732.r65EQFY0-lkp@intel.com
</content>
</entry>
<entry>
<title>cachestat: implement cachestat syscall</title>
<updated>2023-06-09T23:25:16+00:00</updated>
<author>
<name>Nhat Pham</name>
<email>nphamcs@gmail.com</email>
</author>
<published>2023-05-03T01:36:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=cf264e1329fb0307e044f7675849f9f38b44c11a'/>
<id>urn:sha1:cf264e1329fb0307e044f7675849f9f38b44c11a</id>
<content type='text'>
There is currently no good way to query the page cache state of large file
sets and directory trees.  There is mincore(), but it scales poorly: the
kernel writes out a lot of bitmap data that userspace has to aggregate,
when the user really doesn not care about per-page information in that
case.  The user also needs to mmap and unmap each file as it goes along,
which can be quite slow as well.

Some use cases where this information could come in handy:
  * Allowing database to decide whether to perform an index scan or
    direct table queries based on the in-memory cache state of the
    index.
  * Visibility into the writeback algorithm, for performance issues
    diagnostic.
  * Workload-aware writeback pacing: estimating IO fulfilled by page
    cache (and IO to be done) within a range of a file, allowing for
    more frequent syncing when and where there is IO capacity, and
    batching when there is not.
  * Computing memory usage of large files/directory trees, analogous to
    the du tool for disk usage.

More information about these use cases could be found in the following
thread:

https://lore.kernel.org/lkml/20230315170934.GA97793@cmpxchg.org/

This patch implements a new syscall that queries cache state of a file and
summarizes the number of cached pages, number of dirty pages, number of
pages marked for writeback, number of (recently) evicted pages, etc.  in a
given range.  Currently, the syscall is only wired in for x86
architecture.

NAME
    cachestat - query the page cache statistics of a file.

SYNOPSIS
    #include &lt;sys/mman.h&gt;

    struct cachestat_range {
        __u64 off;
        __u64 len;
    };

    struct cachestat {
        __u64 nr_cache;
        __u64 nr_dirty;
        __u64 nr_writeback;
        __u64 nr_evicted;
        __u64 nr_recently_evicted;
    };

    int cachestat(unsigned int fd, struct cachestat_range *cstat_range,
        struct cachestat *cstat, unsigned int flags);

DESCRIPTION
    cachestat() queries the number of cached pages, number of dirty
    pages, number of pages marked for writeback, number of evicted
    pages, number of recently evicted pages, in the bytes range given by
    `off` and `len`.

    An evicted page is a page that is previously in the page cache but
    has been evicted since. A page is recently evicted if its last
    eviction was recent enough that its reentry to the cache would
    indicate that it is actively being used by the system, and that
    there is memory pressure on the system.

    These values are returned in a cachestat struct, whose address is
    given by the `cstat` argument.

    The `off` and `len` arguments must be non-negative integers. If
    `len` &gt; 0, the queried range is [`off`, `off` + `len`]. If `len` ==
    0, we will query in the range from `off` to the end of the file.

    The `flags` argument is unused for now, but is included for future
    extensibility. User should pass 0 (i.e no flag specified).

    Currently, hugetlbfs is not supported.

    Because the status of a page can change after cachestat() checks it
    but before it returns to the application, the returned values may
    contain stale information.

RETURN VALUE
    On success, cachestat returns 0. On error, -1 is returned, and errno
    is set to indicate the error.

ERRORS
    EFAULT cstat or cstat_args points to an invalid address.

    EINVAL invalid flags.

    EBADF  invalid file descriptor.

    EOPNOTSUPP file descriptor is of a hugetlbfs file

[nphamcs@gmail.com: replace rounddown logic with the existing helper]
  Link: https://lkml.kernel.org/r/20230504022044.3675469-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20230503013608.2431726-3-nphamcs@gmail.com
Signed-off-by: Nhat Pham &lt;nphamcs@gmail.com&gt;
Acked-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Cc: Brian Foster &lt;bfoster@redhat.com&gt;
Cc: Matthew Wilcox (Oracle) &lt;willy@infradead.org&gt;
Cc: Michael Kerrisk &lt;mtk.manpages@gmail.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core</title>
<updated>2023-04-27T18:53:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-04-27T18:53:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=556eb8b79190151506187bf0b16dda423c34d9a8'/>
<id>urn:sha1:556eb8b79190151506187bf0b16dda423c34d9a8</id>
<content type='text'>
Pull driver core updates from Greg KH:
 "Here is the large set of driver core changes for 6.4-rc1.

  Once again, a busy development cycle, with lots of changes happening
  in the driver core in the quest to be able to move "struct bus" and
  "struct class" into read-only memory, a task now complete with these
  changes.

  This will make the future rust interactions with the driver core more
  "provably correct" as well as providing more obvious lifetime rules
  for all busses and classes in the kernel.

  The changes required for this did touch many individual classes and
  busses as many callbacks were changed to take const * parameters
  instead. All of these changes have been submitted to the various
  subsystem maintainers, giving them plenty of time to review, and most
  of them actually did so.

  Other than those changes, included in here are a small set of other
  things:

   - kobject logging improvements

   - cacheinfo improvements and updates

   - obligatory fw_devlink updates and fixes

   - documentation updates

   - device property cleanups and const * changes

   - firwmare loader dependency fixes.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'driver-core-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (120 commits)
  device property: make device_property functions take const device *
  driver core: update comments in device_rename()
  driver core: Don't require dynamic_debug for initcall_debug probe timing
  firmware_loader: rework crypto dependencies
  firmware_loader: Strip off \n from customized path
  zram: fix up permission for the hot_add sysfs file
  cacheinfo: Add use_arch[|_cache]_info field/function
  arch_topology: Remove early cacheinfo error message if -ENOENT
  cacheinfo: Check cache properties are present in DT
  cacheinfo: Check sib_leaf in cache_leaves_are_shared()
  cacheinfo: Allow early level detection when DT/ACPI info is missing/broken
  cacheinfo: Add arm64 early level initializer implementation
  cacheinfo: Add arch specific early level initializer
  tty: make tty_class a static const structure
  driver core: class: remove struct class_interface * from callbacks
  driver core: class: mark the struct class in struct class_interface constant
  driver core: class: make class_register() take a const *
  driver core: class: mark class_release() as taking a const *
  driver core: remove incorrect comment for device_create*
  MIPS: vpe-cmp: remove module owner pointer from struct class usage.
  ...
</content>
</entry>
<entry>
<title>Merge tag 'slab-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab</title>
<updated>2023-04-25T20:00:41+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-04-25T20:00:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=736b378b29d89c8c3567fa4b2e948be5568aebb8'/>
<id>urn:sha1:736b378b29d89c8c3567fa4b2e948be5568aebb8</id>
<content type='text'>
Pull slab updates from Vlastimil Babka:
 "The main change is naturally the SLOB removal. Since its deprecation
  in 6.2 I've seen no complaints so hopefully SLUB_(TINY) works well for
  everyone and we can proceed.

  Besides the code cleanup, the main immediate benefit will be allowing
  kfree() family of function to work on kmem_cache_alloc() objects,
  which was incompatible with SLOB. This includes kfree_rcu() which had
  no kmem_cache_free_rcu() counterpart yet and now it shouldn't be
  necessary anymore.

  Besides that, there are several small code and comment improvements
  from Thomas, Thorsten and Vernon"

* tag 'slab-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  mm/slab: document kfree() as allowed for kmem_cache_alloc() objects
  mm/slob: remove slob.c
  mm/slab: remove CONFIG_SLOB code from slab common code
  mm, pagemap: remove SLOB and SLQB from comments and documentation
  mm, page_flags: remove PG_slob_free
  mm/slob: remove CONFIG_SLOB
  mm/slub: fix help comment of SLUB_DEBUG
  mm: slub: make kobj_type structure constant
  slab: Adjust comment after refactoring of gfp.h
</content>
</entry>
<entry>
<title>Merge tag 'printk-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux</title>
<updated>2023-04-25T19:46:48+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-04-25T19:46:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7ec85f3e089aa423a69559bf4555b6218b5a2ef7'/>
<id>urn:sha1:7ec85f3e089aa423a69559bf4555b6218b5a2ef7</id>
<content type='text'>
Pull printk updates from Petr Mladek:

 - Code cleanup and dead code removal

* tag 'printk-for-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk: Remove obsoleted check for non-existent "user" object
  lib/vsprintf: Use isodigit() for the octal number check
  Remove orphaned CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT
</content>
</entry>
<entry>
<title>gcc: disable '-Warray-bounds' for gcc-13 too</title>
<updated>2023-04-23T16:56:20+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-04-23T16:56:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0da6e5fd6c3726723e275603426e09178940dace'/>
<id>urn:sha1:0da6e5fd6c3726723e275603426e09178940dace</id>
<content type='text'>
We started disabling '-Warray-bounds' for gcc-12 originally on s390,
because it resulted in some warnings that weren't realistically fixable
(commit 8b202ee21839: "s390: disable -Warray-bounds").

That s390-specific issue was then found to be less common elsewhere, but
generic (see f0be87c42cbd: "gcc-12: disable '-Warray-bounds' universally
for now"), and then later expanded the version check was expanded to
gcc-11 (5a41237ad1d4: "gcc: disable -Warray-bounds for gcc-11 too").

And it turns out that I was much too optimistic in thinking that it's
all going to go away, and here we are with gcc-13 showing all the same
issues.  So instead of expanding this one version at a time, let's just
disable it for gcc-11+, and put an end limit to it only when we actually
find a solution.

Yes, I'm sure some of this is because the kernel just does odd things
(like our "container_of()" use, but also knowingly playing games with
things like linker tables and array layouts).

And yes, some of the warnings are likely signs of real bugs, but when
there are hundreds of false positives, that doesn't really help.

Oh well.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>mm/slob: remove CONFIG_SLOB</title>
<updated>2023-03-29T08:31:40+00:00</updated>
<author>
<name>Vlastimil Babka</name>
<email>vbabka@suse.cz</email>
</author>
<published>2023-02-27T16:46:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=c9929f0e344a28b3a57b3b84fc237a7dd4134ef8'/>
<id>urn:sha1:c9929f0e344a28b3a57b3b84fc237a7dd4134ef8</id>
<content type='text'>
Remove SLOB from Kconfig and Makefile. Everything under #ifdef
CONFIG_SLOB, and mm/slob.c is now dead code.

Signed-off-by: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Acked-by: Hyeonggon Yoo &lt;42.hyeyoo@gmail.com&gt;
Acked-by: Lorenzo Stoakes &lt;lstoakes@gmail.com&gt;
Acked-by: Mike Rapoport (IBM) &lt;rppt@kernel.org&gt;
</content>
</entry>
</feed>
