diff options
author | Aditya Srivastava <yashsri421@gmail.com> | 2021-02-25 17:21:57 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-26 09:41:04 -0800 |
commit | de93245c00a44578ae73964b7e36607d04fed5b3 (patch) | |
tree | 10d43d87aefc51738097f4064b1fa7414f4e782a /scripts | |
parent | 0972b8bfe0de8c0f05796aceb8f2428b0efb20cd (diff) |
checkpatch: add warning for avoiding .L prefix symbols in assembly files
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.uk
Signed-off-by: Aditya Srivastava <yashsri421@gmail.com>
Suggested-by: Mark Brown <broonie@kernel.org>
Acked-by: Joe Perches <joe@perches.com>
Acked-by: Nick 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'scripts')
-rwxr-xr-x | scripts/checkpatch.pl | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index a04df2657d49..d8793bdbc492 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3599,6 +3599,13 @@ sub process { } } +# check for .L prefix local symbols in .S files + if ($realfile =~ /\.S$/ && + $line =~ /^\+\s*(?:[A-Z]+_)?SYM_[A-Z]+_(?:START|END)(?:_[A-Z_]+)?\s*\(\s*\.L/) { + WARN("AVOID_L_PREFIX", + "Avoid using '.L' prefixed local symbol names for denoting a range of code via 'SYM_*_START/END' annotations; see Documentation/asm-annotations.rst\n" . $herecurr); + } + # check we are in a valid source file C or perl if not then ignore this hunk next if ($realfile !~ /\.(h|c|pl|dtsi|dts)$/); |