Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  If not .svg:
    For each line:
      If doesn't contain `\bxmlns\b`:
        For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
	  If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
            If both the HTTP and HTTPS versions
            return 200 OK and serve the same content:
              Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

While descending directories, Kbuild produces objects for modules,
but do not link final *.ko files; it is done in the modpost.

To keep track of modules, Kbuild creates a *.mod file in $(MODVERDIR)
for every module it is building. Some post-processing steps read the
necessary information from *.mod files. This avoids descending into
directories again. This mechanism was introduced in 2003 or so.

Later, commit 551559e13af1 ("kbuild: implement modules.order") added
modules.order. So, we can simply read it out to know all the modules
with directory paths. This is easier than parsing the first line of
*.mod files.

$(MODVERDIR) has a flat directory structure, that is, *.mod files
are named only with base names. This is based on the assumption that
the module name is unique across the tree. This assumption is really
fragile.

Stephen Rothwell reported a race condition caused by a module name
conflict:

  https://lkml.org/lkml/2019/5/13/991

In parallel building, two different threads could write to the same
$(MODVERDIR)/*.mod simultaneously.

Non-unique module names are the source of all kind of troubles, hence
commit 3a48a91901c5 ("kbuild: check uniqueness of module names")
introduced a new checker script.

However, it is still fragile in the build system point of view because
this race happens before scripts/modules-check.sh is invoked. If it
happens again, the modpost will emit unclear error messages.

To fix this issue completely, create *.mod with full directory path
so that two threads never attempt to write to the same file.

$(MODVERDIR) is no longer needed.

Since modules with directory paths are listed in modules.order, Kbuild
is still able to find *.mod files without additional descending.

I also killed cmd_secanalysis; scripts/mod/sumversion.c computes MD4 hash
for modules with MODULE_VERSION(). When CONFIG_DEBUG_SECTION_MISMATCH=y,
it occurs not only in the modpost stage, but also during directory
descending, where sumversion.c may parse stale *.mod files. It would emit
'No such file or directory' warning when an object consisting a module is
renamed, or when a single-obj module is turned into a multi-obj module or
vice versa.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Nicolas Pitre <nico@fluxnic.net>

header-test-y does not work with headers in sub-directories.

For example, you may want to write a Makefile, like this:

include/linux/Kbuild:

  header-test-y += mtd/nand.h

This entry will create a wrapper include/linux/mtd/nand.hdrtest.c
with the following content:

  #include "mtd/nand.h"

To make this work, we need to add $(srctree)/include/linux to the
header search path. It would be tedious to add ccflags-y.

Instead, we could change the *.hdrtest.c rule to wrap:

  #include "nand.h"

This works for in-tree build since #include "..." searches in the
relative path from the header with this directive. For O=... build,
we need to add $(srctree)/include/linux/mtd to the header search path,
which will be even more tedious.

After all, I thought it would be handier to compile headers directly
without creating wrappers.

I added a new build rule to compile %.h into %.h.s

The target is %.h.s instead of %.h.o because it is slightly faster.
Also, as for GCC, an empty assembly is smaller than an empty object.

I wrote the build rule:

  $(CC) $(c_flags) -S -o $@ -x c /dev/null -include $<

instead of:

  $(CC) $(c_flags) -S -o $@ -x c $<

Both work fine with GCC, but the latter is bad for Clang.

This comes down to the difference in the -Wunused-function policy.
GCC does not warn about unused 'static inline' functions at all.
Clang does not warn about the ones in included headers, but does
about the ones in the source. So, we should handle headers as
headers, not as source files.

In fact, this has been hidden since commit abb2ea7dfd82 ("compiler,
clang: suppress warning for unused static inline functions"), but we
should not rely on that.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>

Zhenzhong Duan reported that running 'make O=/build/kernel binrpm-pkg'
failed with the following errors:

  Running 'make O=/build/kernel binrpm-pkg' failed with below two errors.

  Makefile:600: include/config/auto.conf: No such file or directory

  + cp make -C /mnt/root/kernel O=/build/kernel image_name make -f
  /mnt/root/kernel/Makefile ...
  cp: invalid option -- 'C'
  Try 'cp --help' for more information.

Prior to commit 80463f1b7bf9 ("kbuild: add --include-dir flag only
for out-of-tree build"), both srctree and objtree were added to
--include-dir redundantly, and the wrong code 'make image_name'
was working by relying on that. Now, the potential issue that had
previously been hidden just showed up.

'make image_name' recurses to the generated $(objtree)/Makefile and
ends up with running in srctree, which is incorrect. It should be
invoked with '-f $srctree/Makefile' (or KBUILD_SRC=) to be executed
in objtree.

Fixes: 80463f1b7bf9 ("kbuild: add --include-dir flag only for out-of-tree build")
Reported-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The new-kernel-pkg script is only present when grubby is installed, but it
may not always be the case. So if the script isn't present, attempt to use
the kernel-install script as a fallback instead.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

There is a change in how command line parsing is done in this version.
Excludes and includes are now ordered with the file list. Since
the spec file puts the file list before the exclude list it means newer
tar ignores the excludes and packs all the build output into the
kernel-devel RPM resulting in a huge package.

Simple argument re-ordering fixes the problem.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

$RPM_BUILD_ROOT must be escaped to prevent shell from expanding it
when generating the spec file.

%{build_root} is more readable than \$RPM_BUILD_ROOT.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

When CONFIG_MODULES is disabled, make rpm-pkg / binrpm-pkg fails
with the following message:

  The present kernel configuration has modules disabled.
  Type 'make config' and enable loadable module support.
  Then build a kernel with module support enabled.

Do not install modules in the case.  Also, omit the devel package.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

The repeat of echo is unreadable.  The here-document is a well-known
device for such scripts.  One difficulty is we have a bunch of PREBUILT
conditionals that would split the here-document.

My idea is to add "$S" annotatation to lines only for the source package
spec file, then post-process it by sed.  I hope it will make our life
easier than repeat of "cat <<EOF ..."

I confirmed this commit still produced the same (bin)kernel.spec as
before.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Clean up the mkspec without changing the behavior.

 - grep CONFIG_DRM=y more simply

 - move "EXCLUDE" out of the "%install" section because it can be
   computed when the spec file is generated

 - remove "BuildRoot:" field, which is now redundant

 - do not mkdir $RPM_BUILD_ROOT/lib/modules explicitly because it
   is automatically created by "make modules_install"

 - exclude "%package devel" from source package spec file because
   it does not make sense where "%files devel" is already excluded

 - exclude "%build" from source package spec file

 - remove unneeded "make clean" because we had already cleaned
   before making tar file

 - merge two %ifarch ia64 conditionals

 - replace KBUILD_IMAGE with direct use of $(make image_name)

 - remove trailing empty line from the spec file

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>