ld-version.sh checks the output from $(LD) --version, but it has a
problem on some locales.

For example, in Italian:

  $ LC_MESSAGES=it_IT.UTF-8 ld --version | head -n 1
  ld di GNU (GNU Binutils for Debian) 2.35.2

This makes ld-version.sh fail because it expects "GNU ld" for the
BFD linker case.

Add LC_ALL=C to override the user's locale.

BTW, setting LC_MESSAGES=C (or LANG=C) is not enough because it is
ineffective if LC_ALL is set on the user's environment.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=212105
Reported-by: Marco Scardovi
Reported-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Recensito-da: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: NNathan Chancellor <nathan@kernel.org>

This is a remnant of commit 78046fab ("kbuild: determine the output
format of DTC by the target suffix").

The parameter "yaml" is meaningless because cmd_dtc no loner takes $(2).
Reported-by: NRob Herring <robh@kernel.org>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

This piece of code converts the target suffix to the dtc -O option:

    *.dtb      ->  -O dtb
    *.dt.yaml  ->  -O yaml

Commit ce88c9c7 ("kbuild: Add support to build overlays (%.dtbo)")
added the third case:

    *.dtbo     ->  -O dtbo

This works thanks to commit 163f0469bf2e ("dtc: Allow overlays to have
.dtbo extension") in the upstream DTC, which has already been pulled in
the kernel.

However, I think it is a bit odd because "dtbo" is not a format name.
At least, it does not show up in the help message of dtc.

$ scripts/dtc/dtc --help
  [ snip ]
  -O, --out-format <arg>
        Output formats are:
                dts - device tree source text
                dtb - device tree blob
                yaml - device tree encoded as YAML
                asm - assembler source

So, I am not a big fan of the second hunk of that change:

        } else if (streq(outform, "dtbo")) {
                dt_to_blob(outf, dti, outversion);

Anyway, we did not need to do this in Makefile in the first place.

guess_type_by_name() had already understood ".yaml" before commit
4f0e3a57 ("kbuild: Add support for DT binding schema checks"),
and now does ".dtbo" as well.

Makefile does not need to duplicate the same logic. Let's leave it
to dtc.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Reviewed-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NRob Herring <robh@kernel.org>

Commit aec6c60a ("kbuild: check the minimum compiler version in
Kconfig") changed how the script detects the compiler version.

Get 'make CROSS_COMPILE=scripts/dummy-tools/' back working again.

Fixes: aec6c60a ("kbuild: check the minimum compiler version in Kconfig")
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Reviewed-by: NNathan Chancellor <nathan@kernel.org>
Tested-by: NNathan Chancellor <nathan@kernel.org>
Acked-by: NMiguel Ojeda <ojeda@kernel.org>

ppc64le checks for -mprofile-kernel to define MPROFILE_KERNEL Kconfig.
Kconfig calls arch/powerpc/tools/gcc-check-mprofile-kernel.sh for that
purpose. This script performs two checks:
1) build with -mprofile-kernel should contain "_mcount"
2) build with -mprofile-kernel with a function marked as "notrace"
   should not produce "_mcount"

So support this in dummy-tools' gcc, so that we have MPROFILE_KERNEL
always true.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Linus reported a build error due to the GCC plugin incompatibility
when the compiler is upgraded. [1]

GCC plugins are tied to a particular GCC version. So, they must be
rebuilt when the compiler is upgraded.

This seems to be a long-standing flaw since the initial support of
GCC plugins.

Extend commit 8b59cd81 ("kbuild: ensure full rebuild when the
compiler is updated"), so that GCC plugins are covered by the
compiler upgrade detection.

[1]: https://lore.kernel.org/lkml/CAHk-=wieoN5ttOy7SnsGwZv+Fni3R6m-Ut=oxih6bbZ28G+4dw@mail.gmail.com/Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Reviewed-by: NKees Cook <keescook@chromium.org>

If LLD was built with -DLLD_VENDOR="xyz", ld.lld --version output
will prefix LLD_VENDOR. Since LLD_VENDOR can contain spaces, the
LLD identifier isn't guaranteed to be $2 either.

Adjust the version checker to handle such versions of lld.

Link: https://lore.kernel.org/lkml/20210302221211.1620858-1-bero@lindev.ch/Signed-off-by: NBernhard Rosenkränzer <bero@lindev.ch>
[masahiro yamada: refactor the code]
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Reviewed-by: NNathan Chancellor <nathan@kernel.org>
Tested-by: NNathan Chancellor <nathan@kernel.org>

There is a test in Kconfig which takes inverted value of a compiler
check:
* config CC_HAS_INT128
        def_bool !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0)

This results in CC_HAS_INT128 not being in super-config generated by
dummy-tools. So take this into account in the gcc script.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

On little endian system, Use aarch64_be(gcc v7.3) downloaded from
linaro.org to build image with CONFIG_CPU_BIG_ENDIAN = y,
CONFIG_FTRACE = y, CONFIG_DYNAMIC_FTRACE = y.

gcc will create symbols of _mcount but recordmcount can not create
mcount_loc for *.o.
aarch64_be-linux-gnu-objdump -r fs/namei.o | grep mcount
00000000000000d0 R_AARCH64_CALL26  _mcount
...
0000000000007190 R_AARCH64_CALL26  _mcount

The reason is than funciton arm64_is_fake_mcount can not work correctly.
A symbol of _mcount in *.o compiled with big endian compiler likes:
00 00 00 2d 00 00 01 1b
w(rp->r_info) will return 0x2d instead of 0x011b. Because w() takes
uint32_t as parameter, which truncates rp->r_info.

Use w8() instead w() to read relp->r_info

Link: https://lkml.kernel.org/r/20210222135840.56250-1-chenjun102@huawei.com

Fixes: ea0eada4 ("recordmcount: only record relocation of type R_AARCH64_CALL26 on arm64.")
Acked-by: NWill Deacon <will@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NSteven Rostedt (VMware) <rostedt@goodmis.org>

Fix the following coccicheck warning:

scripts/gcc-plugins/latent_entropy_plugin.c:539:2-3: Unneeded semicolon
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NJason Yan <yanaijie@huawei.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200418070521.10931-1-yanaijie@huawei.com

Fix the following coccicheck warning:

scripts/gcc-plugins/structleak_plugin.c:177:14-17: Unneeded variable:
"ret". Return "0" on line 207
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NJason Yan <yanaijie@huawei.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200418070505.10715-1-yanaijie@huawei.com

Commit cd195bc4 ("kbuild: split adjust_autoksyms.sh in two parts")
split out the code that needs include/config/auto.conf.

This script no longer needs to include include/config/auto.conf.

Fixes: cd195bc4 ("kbuild: split adjust_autoksyms.sh in two parts")
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Commit fbe078d3 ("kbuild: lto: add a default list of used symbols")
does not work as expected if the .config file has already specified
CONFIG_UNUSED_KSYMS_WHITELIST="my/own/white/list" before enabling
CONFIG_LTO_CLANG.

So, the user-supplied whitelist and LTO-specific white list must be
independent of each other.

I refactored the shell script so CONFIG_MODVERSIONS and CONFIG_CLANG_LTO
handle whitelists in the same way.

Fixes: fbe078d3 ("kbuild: lto: add a default list of used symbols")
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>

Some randconfig builds fail with undefined references to _mcount
when CONFIG_TRIM_UNUSED_KSYMS is set:

ERROR: modpost: "_mcount" [drivers/tee/optee/optee.ko] undefined!
ERROR: modpost: "_mcount" [drivers/fsi/fsi-occ.ko] undefined!
ERROR: modpost: "_mcount" [drivers/fpga/dfl-pci.ko] undefined!

Since there is already a list of symbols that get generated at link
time, add this one as well.

Fixes: fbe078d3 ("kbuild: lto: add a default list of used symbols")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Since GCC 8.0 -fsanitize=signed-integer-overflow doesn't work with
-fwrapv.  -fwrapv makes signed overflows defines and GCC essentially
disables ubsan checks.  On GCC < 8.0 -fwrapv doesn't have influence on
-fsanitize=signed-integer-overflow setting, so it kinda works but
generates false-positves and violates uaccess rules:

lib/iov_iter.o: warning: objtool: iovec_from_user()+0x22d: call to
__ubsan_handle_add_overflow() with UACCESS enabled

Disable signed overflow checks to avoid these problems.  Remove unsigned
overflow checks as well.  Unsigned overflow appeared as side effect of
commit cdf8a76f ("ubsan: move cc-option tests into Kconfig"), but it
never worked (kernel doesn't boot).  And unsigned overflows are allowed by
C standard, so it just pointless.

Link: https://lkml.kernel.org/r/20210209232348.20510-1-ryabinin.a.a@gmail.comSigned-off-by: NAndrey Ryabinin <ryabinin.a.a@gmail.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If the list is uninitialized (next pointer is NULL), list_for_each gets
stuck in an infinite loop. Print a message and treat list as empty.

Link: https://lkml.kernel.org/r/4ae23bb1-c333-f669-da2d-fa35c4f49018@amazon.comSigned-off-by: NGeorge Prekas <prekageo@amazon.com>
Reviewed-by: NJan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

BPF programs explicitly initialise global variables to 0 to make sure
clang (v10 or older) do not put the variables in the common section.  Skip
"initialise globals to 0" check for BPF programs to elimiate error
messages like:

    ERROR: do not initialise globals to 0
    #19: FILE: samples/bpf/tracex1_kern.c:21:

Link: https://lkml.kernel.org/r/20210209211954.490077-1-songliubraving@fb.comSigned-off-by: NSong Liu <songliubraving@fb.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This check erroneously flags cases like the one in my recent printk
enumeration patch[0], where the spaces are syntactic, and `section:' vs.
`section :' is syntactically important:

    ERROR: space prohibited before that ':' (ctx:WxW)
    #258: FILE: include/asm-generic/vmlinux.lds.h:314:
    +       .printk_fmts : AT(ADDR(.printk_fmts) - LOAD_OFFSET) {

0: https://lore.kernel.org/patchwork/patch/1375749/

Link: https://lkml.kernel.org/r/YBwhqsc2TIVeid3t@chrisdown.name
Link: https://lkml.kernel.org/r/YB6UsjCOy1qrrlSD@chrisdown.nameSigned-off-by: NChris Down <chris@chrisdown.name>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 5799b255 ("include/linux/slab.h: add kmalloc_array_node() and
kcalloc_node()") was added in 2017.  Update the unnecessary OOM message
test to include it.

Link: https://lkml.kernel.org/r/b9dc4a808b1518e08ab8761480d9872e5d18e7cd.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Reported-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

objtool requires that all code must be contained in an ELF symbol.  Symbol
names that have a '.L' prefix do not emit symbol table entries, as they
have special meaning for the assembler.

'.L' prefixed symbols can be used within a code region, but should be
avoided for denoting a range of code via 'SYM_*_START/END' annotations.

Add a new check to emit a warning on finding the usage of '.L' symbols for
'.S' files, if it denotes range of code via SYM_*_START/END annotation
pair.

Link: https://lkml.kernel.org/r/20210123190459.9701-1-yashsri421@gmail.com
Link: https://lore.kernel.org/lkml/20210112210154.GI4646@sirena.org.ukSigned-off-by: NAditya Srivastava <yashsri421@gmail.com>
Suggested-by: NMark Brown <broonie@kernel.org>
Acked-by: NJoe Perches <joe@perches.com>
Acked-by: NNick Desaulniers <ndesaulniers@google.com>
Cc: Aditya Srivastava <yashsri421@gmail.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Improve the TYPECAST_INT_CONSTANT test by showing the suggested conversion
for various type of uses like (unsigned int)1 to 1U.

Link: https://lkml.kernel.org/r/ecefe8dcb93fe7028311b69dd297ba52224233d4.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Prefer using ftrace over function entry/exit logging messages.

Warn with various function entry/exit only logging that only
use __func__ with or without descriptive decoration.

Link: https://lkml.kernel.org/r/47c01081533a417c99c9a80a4cd537f8c308503f.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Indentations should use tabs wherever possible.
Replace spaces by tabs for indents.

Link: https://lkml.kernel.org/r/20210105103044.40282-1-dwaipayanray1@gmail.comSigned-off-by: NDwaipayan Ray <dwaipayanray1@gmail.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some max_length wants to hold as large room as possible to ensure enough
size to tackle with the biggest NR_CPUS.  An example below:

kernel/cgroup/cpuset.c:
static struct cftype legacy_files[] = {
        {
                .name = "cpus",
                .seq_show = cpuset_common_seq_show,
                .write = cpuset_write_resmask,
                .max_write_len = (100U + 6 * NR_CPUS),
                .private = FILE_CPULIST,
        },
	...
}

Link: https://lkml.kernel.org/r/5d4998aa8a8ac7efada2c7daffa9e73559f8b186.1609331255.git.rocking@linux.alibaba.comSigned-off-by: NPeng Wang <rocking@linux.alibaba.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Avoid multiple false positives by ignoring attributes.

Various attributes like volatile and ____cacheline_aligned_in_smp cause
checkpatch to emit invalid "Missing a blank line after declarations"
messages.

Use copies of $sline and $prevline, remove $Attribute and $Sparse, and use
the existing tests to avoid these false positives.

Miscellanea:

o Add volatile to $Attribute

This also reduces checkpatch runtime a bit by moving the indentation
comparison test to the start of the block to avoid multiple unnecessary
regex tests.

Link: https://lkml.kernel.org/r/9015fd00742bf4e5b824ad6d7fd7189530958548.camel@perches.comSigned-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Here are some of the more common spelling mistakes and typos that I've
found while fixing up spelling mistakes in the kernel since September 2020

Link: https://lkml.kernel.org/r/20210210124318.55082-1-colin.king@canonical.comSigned-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Increase "allocted" and "exeeds" spelling error check.

Link: https://lkml.kernel.org/r/20210127081919.1928-1-dingsenjie@163.comSigned-off-by: Ndingsenjie <dingsenjie@yulong.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Increase exeeds spelling error check.

Link: https://lkml.kernel.org/r/20210127060049.915-1-zuoqilin1@163.comSigned-off-by: Nzuoqilin <zuoqilin@yulong.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Increase maping spelling error check.

Link: https://lkml.kernel.org/r/20210121092125.2663-1-tangchunyou@163.comSigned-off-by: NWenZhang <zhangwen@yulong.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

These have no more user in the upstream code. The use of them has been
warned for a while for external modules. The migration is finished.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Unify the similar build rules.

This supports 'make build_config', which builds scripts/kconfig/conf
but does not invoke it.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

scripts/kconfig/conf.c line 39 defines the default of input_mode as
oldaskconfig. Hence, 'make config' works in the same way even without
the --oldaskconfig option given. Note this in the help message.

This will be helpful to unify build rules in Makefile in the next
commit.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

scripts/kconfig/conf supports -? option to show the help message.
This is not wired up to Makefile, so nobody would notice this, but
it also shows 'invalid option' message.

  $ ./scripts/kconfig/conf -?
  ./scripts/kconfig/conf: invalid option -- '?'
  Usage: ./scripts/kconfig/conf [-s] [option] <kconfig-file>
  [option] is _one_ of the following:
    --listnewconfig         List new options
    --helpnewconfig         List new options and help text
    --oldaskconfig          Start a new configuration using a line-oriented program
    ...

The reason is the '?' is missing in the short option list passed to
getopt_long().

While I fixed this issue, I also changed the option '?' to 'h'.
I prefer -h (or --help, if a long option is also desired).
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

conf_askvalue() is only called for oldconfig, syncconfig, and
oldaskconfig. If it is called for other cases, it is a bug.

So, the code after the switch statement is unreachable.

Remove the dead code, and clean up the switch statement.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Unify the outer two if-conditionals into one. This decreases the
indent level by one.

Also, change the if-else blocks:

    if (input_mode == listnewconfig) {
            ...
    } else if (input_mode == helpnewconfig) {
            ...
    } else {
            ...
    }

into the switch statement.
Signed-off-by: NMasahiro Yamada <masahiroy@kernel.org>

Use the saved returned value of sym_get_string_value() instead of
calling it twice.
Signed-off-by: NMickaël Salaün <mic@linux.microsoft.com>
Link: https://lore.kernel.org/r/20210215181511.2840674-2-mic@digikod.netSigned-off-by: NMasahiro Yamada <masahiroy@kernel.org>

With c6x architecture removal, scripts/dtc/include-prefixes/c6x symlink
lost its target. Drop the dangling symlink which triggers some distribution
check scripts.

Fixes: a579fcfa ("c6x: remove architecture")
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210223204114.E7F55E0155@unicorn.suse.cz

Commit 0da6bcd9 ("scripts: dtc: Build fdtoverlay tool") enabled
building fdtoverlay, but failed to add it to .gitignore.

Also add a note to keep hostprogs in sync with .gitignore.

Fixes: 0da6bcd9 ("scripts: dtc: Build fdtoverlay tool")
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NRob Herring <robh@kernel.org>

With LTO, LLVM bitcode won't be compiled into native code until
modpost_link, or modfinal for modules. This change postpones calls
to objtool until after these steps, and moves objtool_args to
Makefile.lib, so the arguments can be reused in Makefile.modfinal.

As we didn't have objects to process earlier, we use --duplicate
when processing vmlinux.o. This change also disables unreachable
instruction warnings with LTO to avoid warnings about the int3
padding between functions.
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>
Reviewed-by: NKees Cook <keescook@chromium.org>

This change adds a --noinstr flag to objtool to allow us to specify
that we're processing vmlinux.o without also enabling noinstr
validation. This is needed to avoid false positives with LTO when we
run objtool on vmlinux.o without CONFIG_DEBUG_ENTRY.
Signed-off-by: NSami Tolvanen <samitolvanen@google.com>