Passing NULL to free() is allowed and is a no-op.

Remove redundant NULL pointer checks.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Remove the unreachable code detected by clang.

  $ make HOSTCC=clang HOSTCFLAGS=-Wunreachable-code defconfig
    [ snip ]
  scripts/kconfig/expr.c:1134:2: warning: code will never be executed [-Wunreachable-code]
          printf("[%dgt%d?]", t1, t2);
          ^~~~~~
  1 warning generated.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

menu_has_help() and menu_get_help() functions are only used within
menu_get_ext_help().

Squash them into menu_get_ext_help(). It revealed the if-conditional
in menu_get_help() was unneeded, as menu_has_help() has already checked
that menu->help is not NULL.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Separate out the duplicated code to mnconf-common.c.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

$(addprefix ) is slightly shorter and more intuitive.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>

Add objects to obj-y in a more straightforward way.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>

Currently, vdso-image-*.c, vdso*.so, vdso*.so.dbg are not cleaned
because 'make clean' does not include include/config/auto.conf,
resulting in $(vdso_img-y) being empty.

Add the build artifacts to 'targets' unconditionally.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>

Now compilers can recognize fatal() never returns.

While GCC 4.5 dropped support for -Wunreachable-code, Clang is capable
of detecting the unreachable code.

  $ make HOSTCC=clang HOSTCFLAGS=-Wunreachable-code-return
      [snip]
    HOSTCC  scripts/mod/modpost.o
  scripts/mod/modpost.c:520:11: warning: 'return' will never be executed [-Wunreachable-code-return]
                          return 0;
                                 ^
  scripts/mod/modpost.c:477:10: warning: 'return' will never be executed [-Wunreachable-code-return]
                  return 0;
                         ^
  2 warnings generated.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>

This initializer was added to avoid -Wmaybe-uninitialized (gcc) and
-Wsometimes-uninitialized (clang) warnings.

Now that compilers recognize fatal() never returns, it is unneeded.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>

The function fatal() never returns because modpost_log() calls exit(1)
when LOG_FATAL is passed.

Inform compilers of this fact so that unreachable code flow can be
identified at compile time.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>

This attribute must be added to the function declaration in a header
for comprehensive checking of all the callsites.

Fixes: 6d9a89ea ("kbuild: declare the modpost error functions as printf like")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>

When using the -dtbs syntax, you need to list the base first, as
follows:

    foo-dtbs := foo_base.dtb foo_overlay1.dtbo foo_overlay2.dtbo
    dtb-y := foo.dtb

You cannot do this arrangement:

    foo-dtbs := foo_overlay1.dtbo foo_overlay2.dtbo foo_base.dtb

This restriction comes from $(firstword ...) in the current
implementation, but it is unneeded to rely on the order in the
-dtbs syntax.

Instead, you can simply determine the base by the suffix because
the base (*.dtb) and overlays (*.dtbo) use different suffixes.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

In 2017, the dpkg suite introduced the rootless builds support with the
following commits:

  - 2436807c87b0 ("dpkg-deb: Add support for rootless builds")
  - fca1bfe84068 ("dpkg-buildpackage: Add support for rootless builds")

This feature is available in the default dpkg on Debian 10 and Ubuntu
20.04.

Remove the old method.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Commit f5016932 ("module.h: split out the EXPORT_SYMBOL into
export.h") appropriately separated EXPORT_SYMBOL into <linux/export.h>
because modules and EXPORT_SYMBOL are orthogonal; modules are symbol
consumers, while EXPORT_SYMBOL are used by symbol providers, which
may not be necessarily a module.

However, that commit also relocated THIS_MODULE. As explained in the
commit description, the intention was to define THIS_MODULE in a
lightweight header, but I do not believe <linux/export.h> was the
best location because EXPORT_SYMBOL and THIS_MODULE are unrelated.

Move it to another lightweight header, <linux/init.h>. The reason for
choosing <linux/init.h> is to make <linux/moduleparam.h> self-contained
without relying on <linux/linkage.h> incorrectly including
<linux/export.h>.

With this adjustment, the role of <linux/export.h> becomes clearer as
it only defines EXPORT_SYMBOL.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>

When a default property is missing in an int or hex symbol, it defaults
to an empty string, which is not a valid symbol value.

It results in an incorrect .config, and can also lead to an infinite
loop in scripting.

Use "0" for int and "0x0" for hex as a default value.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Yoann Congal <yoann.congal@smile.fr>

This is used only for initializing other variables.

Use the empty string "" directly.

Please note newval.tri is unused for S_INT/HEX/STRING.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

A little more janitorial work after commit cf8e8658 ("arch: Remove
Itanium (IA-64) architecture").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>

KCONFIG_WARN_UNKNOWN_SYMBOLS=1 and KCONFIG_WERROR=1 are descriptive
and suitable in scripting, but typing them from the command line can
be tedious.

Associate them with KBUILD_EXTRA_WARN (and the W= shorthand).

Support a new letter 'c' to enable extra checks in Kconfig. You can
still manage compiler warnings (W=1) and Kconfig warnings (W=c)
independently.

Reuse the letter 'e' to turn Kconfig warnings into errors.

As usual, you can combine multiple letters in KCONFIG_EXTRA_WARN.

  $ KCONFIG_WARN_UNKNOWN_SYMBOLS=1 KCONFIG_WERROR=1 make defconfig

can be shortened to:

  $ KBUILD_EXTRA_WARN=ce make defconfig

or, even shorter:

  $ make W=ce defconfig
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>

The rpm-pkg and deb-pkg targets have transitioned to using 'git archive'
for tarball creation.

Although the old cmd_src_tar is still used by snap-pkg, there is no need
to pack and unpack a tarball solely for passing the source to snapcraft.

Instead, you can use 'source-type: local' to tell the source location to
snapcraft.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

It is done for the same reasons as 4243afdb does it for builddeb:
always runs make modules to install modules.builtin* files, which are
needed for e.g. initramfs-tools or LTP testing tool.
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The shell variable $dirs is not used any more since 1fc90958
("kbuild: tar-pkg: use tar rules in scripts/Makefile.package"),
therefore remove it".

Fixes: 1fc90958 ("kbuild: tar-pkg: use tar rules in scripts/Makefile.package")
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Make the while-loop code a little more readable.

The gain is that "CONFIG_FOO" without '=' is warned as unexpected data.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Currently, any string starting "is not set" disables a CONFIG option.

For example, "# CONFIG_FOO is not settled down" is accepted as valid
input, functioning the same as "# CONFIG_FOO is not set". It is a
long-standing oddity.

Check the line against the exact pattern "is not set".
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Currently, newline characters are stripped away in multiple places
on the caller.

Doing that in the callee is helpful for further cleanups.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Kconfig accepts both "# CONFIG_FOO is not set" and "CONFIG_FOO=n" as
a valid input, but conf_read_simple() duplicates similar code to handle
them. Factor out the common code.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The 'else' arm here is unreachable in practical use cases.

include/config/auto.conf does not include "# CONFIG_... is not set"
line unless it is manually hacked.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Currently, when an input line starts with '#', (line + 2) is passed to
memcmp() without checking line[1].

It means that line[1] can be any arbitrary character. For example,
"#KCONFIG_FOO is not set" is accepted as valid input, functioning the
same as "# CONFIG_FOO is not set".

More importantly, this can potentially lead to a buffer overrun if
line[1] == '\0'. It occurs if the input only contains '#', as
(line + 2) points to an uninitialized buffer.

Check line[1], and skip the line if it is not a space.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

xrealloc() never returns NULL as it is checked in the callee.

This is a left-over of commit d717f24d ("kconfig: add xrealloc()
helper").
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

The long version --rules-file and --jobs are available since 1.18.8
while their short analogues -R and -j have been added since 1.14.7.

The option --rules-file the way it works currently was introduced in the
commit 5cd52673aabdf5eaa58181972119a41041fc85f2 of dpkg dated 23.07.18
with the following changelog entry:

* Fix dpkg-buildpackage option --rules-file parsing. It was trying to parse
  it as --rules-target, which due to the ordering was a no-op.

The current behavior of the long version --rules-file is guaranteed to
be in use starting 1.19.1 and might cause build failures for some
versions newer than 1.18.8 even in spite of being documented that way.
Signed-off-by: Dmitrii Bundin <dmitrii.bundin.a@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

When a user-supplied value is out of range, (NEW) and an incorrect default
value are shown.

[Test Kconfig]

  config FOO
          int "foo"
          range 10 20

[Test .config]

  CONFIG_FOO=30

[Result without this fix]

  $ make config
  *
  * Main menu
  *
  foo (FOO) [10] (NEW)

[Result with this fix]

  $ make config
  *
  * Main menu
  *
  foo (FOO) [20]

Currently, the SYMBOL_DEF_USER is cleared if the user input does not
reside within the range. Kconfig forgets the initial value 30, and
prints (NEW) and an incorrect default [10].

Kconfig should remember the user's input. The default should be [20]
because the user's input, 30, is closer to the upper limit of the range.

Please note it will not show up in "make oldconfig" because it is no
longer considered as a new symbol. It also fixes the inconsistent
behavior in listnewconfig/helpnewconfig.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

getopt_long() is used by various tools in the kernel (e.g. Kconfig).

It should be fine to use it all the time.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Commit 74d93171 ("genksyms: remove symbol prefix support") removed
the -s (--symbol-prefix) option.

Clean up the left-over.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

Pull tracing fixes from Steven Rostedt::
 "Eventfs fixes:

   - With the usage of simple_recursive_remove() recommended by Al Viro,
     the code should not be calling "d_invalidate()" itself. Doing so is
     causing crashes. The code was calling d_invalidate() on the race of
     trying to look up a file while the parent was being deleted. This
     was detected, and the added dentry was having d_invalidate() called
     on it, but the deletion of the directory was also calling
     d_invalidate() on that same dentry.

   - A fix to not free the eventfs_inode (ei) until the last dput() was
     called on its ei->dentry made the ei->dentry exist even after it
     was marked for free by setting the ei->is_freed. But code elsewhere
     still was checking if ei->dentry was NULL if ei->is_freed is set
     and would trigger WARN_ON if that was the case. That's no longer
     true and there should not be any warnings when it is true.

   - Use GFP_NOFS for allocations done under eventfs_mutex. The
     eventfs_mutex can be taken on file system reclaim, make sure that
     allocations done under that mutex do not trigger file system
     reclaim.

   - Clean up code by moving the taking of inode_lock out of the helper
     functions and into where they are needed, and not use the parameter
     to know to take it or not. It must always be held but some callers
     of the helper function have it taken when they were called.

   - Warn if the inode_lock is not held in the helper functions.

   - Warn if eventfs_start_creating() is called without a parent. As
     eventfs is underneath tracefs, all files created will have a parent
     (the top one will have a tracefs parent).

  Tracing update:

   - Add Mathieu Desnoyers as an official reviewer of the tracing subsystem"

* tag 'trace-v6.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  MAINTAINERS: TRACING: Add Mathieu Desnoyers as Reviewer
  eventfs: Make sure that parent->d_inode is locked in creating files/dirs
  eventfs: Do not allow NULL parent to eventfs_start_creating()
  eventfs: Move taking of inode_lock into dcache_dir_open_wrapper()
  eventfs: Use GFP_NOFS for allocation when eventfs_mutex is held
  eventfs: Do not invalidate dentry in create_file/dir_dentry()
  eventfs: Remove expectation that ei->is_freed means ei->dentry == NULL

Pull parisc architecture fixes from Helge Deller:
 "This patchset fixes and enforces correct section alignments for the
  ex_table, altinstructions, parisc_unwind, jump_table and bug_table
  which are created by inline assembly.

  Due to not being correctly aligned at link & load time they can
  trigger unnecessarily the kernel unaligned exception handler at
  runtime. While at it, I switched the bug table to use relative
  addresses which reduces the size of the table by half on 64-bit.

  We still had the ENOSYM and EREMOTERELEASE errno symbols as left-overs
  from HP-UX, which now trigger build-issues with glibc. We can simply
  remove them.

  Most of the patches are tagged for stable kernel series.

  Summary:

   - Drop HP-UX ENOSYM and EREMOTERELEASE return codes to avoid glibc
     build issues

   - Fix section alignments for ex_table, altinstructions, parisc unwind
     table, jump_table and bug_table

   - Reduce size of bug_table on 64-bit kernel by using relative
     pointers"

* tag 'parisc-for-6.7-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
  parisc: Reduce size of the bug_table on 64-bit kernel by half
  parisc: Drop the HP-UX ENOSYM and EREMOTERELEASE error codes
  parisc: Use natural CPU alignment for bug_table
  parisc: Ensure 32-bit alignment on parisc unwind section
  parisc: Mark lock_aligned variables 16-byte aligned on SMP
  parisc: Mark jump_table naturally aligned
  parisc: Mark altinstructions read-only and 32-bit aligned
  parisc: Mark ex_table entries 32-bit aligned in uaccess.h
  parisc: Mark ex_table entries 32-bit aligned in assembly.h

Pull x86 microcode fixes from Ingo Molnar:
 "Fix/enhance x86 microcode version reporting: fix the bootup log spam,
  and remove the driver version announcement to avoid version confusion
  when distros backport fixes"

* tag 'x86-urgent-2023-11-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode: Rework early revisions reporting
  x86/microcode: Remove the driver announcement and version

Pull x86 perf event fix from Ingo Molnar:
 "Fix a bug in the Intel hybrid CPUs hardware-capabilities enumeration
  code resulting in non-working events on those platforms"

* tag 'perf-urgent-2023-11-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Correct incorrect 'or' operation for PMU capabilities

Pull locking fix from Ingo Molnar:
 "Fix lockdep block chain corruption resulting in KASAN warnings"

* tag 'locking-urgent-2023-11-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Fix block chain corruption

Pull smb client fixes from Steve French:

 - use after free fix in releasing multichannel interfaces

 - fixes for special file types (report char, block, FIFOs properly when
   created e.g. by NFS to Windows)

 - fixes for reporting various special file types and symlinks properly
   when using SMB1

* tag '6.7-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: client: introduce cifs_sfu_make_node()
  smb: client: set correct file type from NFS reparse points
  smb: client: introduce ->parse_reparse_point()
  smb: client: implement ->query_reparse_point() for SMB1
  cifs: fix use after free for iface while disabling secondary channels