From: Aditya Srivastava <yashsri421@gmail.com> To: joe@perches.com Cc: yashsri421@gmail.com, lukas.bulwahn@gmail.com, dwaipayanray1@gmail.com, broonie@kernel.org, ndesaulniers@google.com, jpoimboe@redhat.com, linux-kernel-mentees@lists.linuxfoundation.org, clang-built-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: [PATCH v3] checkpatch: add warning for avoiding .L prefix symbols in assembly files Date: Sun, 24 Jan 2021 00:34:59 +0530 [thread overview] Message-ID: <20210123190459.9701-1-yashsri421@gmail.com> (raw) In-Reply-To: <f23f4003-0017-d52a-39b9-2737e60182bb@gmail.com> 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. Suggested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/lkml/20210112210154.GI4646@sirena.org.uk Signed-off-by: Aditya Srivastava <yashsri421@gmail.com> --- * Applies perfectly on next-20210122 Changes in v3: - Modify regex for SYM_*_START/END pair - remove check for arch/x86/entry/* and arch/x86/lib/* - change 'Link:' in commit message to lkml - Modify commit description accordingly Changes in v2: - Reduce the check to only SYM_*_START/END lines - Reduce the check for only .S files in arch/x86/entry/* and arch/x86/lib/* as suggested by Josh and Nick - Modify commit message scripts/checkpatch.pl | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 7030c4d6d126..4a03326c87b6 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3590,6 +3590,13 @@ 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)$/); -- 2.17.1
WARNING: multiple messages have this Message-ID (diff)
From: Aditya Srivastava <yashsri421@gmail.com> To: joe@perches.com Cc: yashsri421@gmail.com, dwaipayanray1@gmail.com, ndesaulniers@google.com, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, broonie@kernel.org, jpoimboe@redhat.com, linux-kernel-mentees@lists.linuxfoundation.org Subject: [Linux-kernel-mentees] [PATCH v3] checkpatch: add warning for avoiding .L prefix symbols in assembly files Date: Sun, 24 Jan 2021 00:34:59 +0530 [thread overview] Message-ID: <20210123190459.9701-1-yashsri421@gmail.com> (raw) In-Reply-To: <f23f4003-0017-d52a-39b9-2737e60182bb@gmail.com> 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. Suggested-by: Mark Brown <broonie@kernel.org> Link: https://lore.kernel.org/lkml/20210112210154.GI4646@sirena.org.uk Signed-off-by: Aditya Srivastava <yashsri421@gmail.com> --- * Applies perfectly on next-20210122 Changes in v3: - Modify regex for SYM_*_START/END pair - remove check for arch/x86/entry/* and arch/x86/lib/* - change 'Link:' in commit message to lkml - Modify commit description accordingly Changes in v2: - Reduce the check to only SYM_*_START/END lines - Reduce the check for only .S files in arch/x86/entry/* and arch/x86/lib/* as suggested by Josh and Nick - Modify commit message scripts/checkpatch.pl | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index 7030c4d6d126..4a03326c87b6 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -3590,6 +3590,13 @@ 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)$/); -- 2.17.1 _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees
next prev parent reply other threads:[~2021-01-23 19:07 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-01-20 7:25 [PATCH] checkpatch: add warning for avoiding .L prefix symbols in assembly files Aditya Srivastava 2021-01-20 7:25 ` [Linux-kernel-mentees] " Aditya Srivastava 2021-01-20 9:21 ` Joe Perches 2021-01-20 9:21 ` [Linux-kernel-mentees] " Joe Perches 2021-01-20 12:53 ` Aditya 2021-01-20 12:53 ` [Linux-kernel-mentees] " Aditya 2021-01-20 18:43 ` Joe Perches 2021-01-20 18:43 ` [Linux-kernel-mentees] " Joe Perches 2021-01-20 18:57 ` Nick Desaulniers 2021-01-20 18:57 ` [Linux-kernel-mentees] " Nick Desaulniers via Linux-kernel-mentees 2021-01-20 22:59 ` Josh Poimboeuf 2021-01-20 22:59 ` [Linux-kernel-mentees] " Josh Poimboeuf 2021-01-22 13:18 ` Aditya 2021-01-22 13:18 ` [Linux-kernel-mentees] " Aditya 2021-01-22 19:10 ` Joe Perches 2021-01-22 19:10 ` [Linux-kernel-mentees] " Joe Perches 2021-01-22 20:13 ` Aditya 2021-01-22 20:13 ` [Linux-kernel-mentees] " Aditya 2021-01-22 20:36 ` Fāng-ruì Sòng 2021-01-22 20:36 ` [Linux-kernel-mentees] " Fāng-ruì Sòng via Linux-kernel-mentees 2021-01-23 15:14 ` [PATCH v2] " Aditya Srivastava 2021-01-23 15:14 ` [Linux-kernel-mentees] " Aditya Srivastava 2021-01-23 17:21 ` Joe Perches 2021-01-23 17:21 ` [Linux-kernel-mentees] " Joe Perches 2021-01-23 18:23 ` Aditya 2021-01-23 18:23 ` [Linux-kernel-mentees] " Aditya 2021-01-23 19:04 ` Aditya Srivastava [this message] 2021-01-23 19:04 ` [Linux-kernel-mentees] [PATCH v3] " Aditya Srivastava 2021-01-23 21:01 ` Joe Perches 2021-01-23 21:01 ` [Linux-kernel-mentees] " Joe Perches 2021-01-25 18:15 ` Nick Desaulniers 2021-01-25 18:15 ` [Linux-kernel-mentees] " Nick Desaulniers via Linux-kernel-mentees
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20210123190459.9701-1-yashsri421@gmail.com \ --to=yashsri421@gmail.com \ --cc=broonie@kernel.org \ --cc=clang-built-linux@googlegroups.com \ --cc=dwaipayanray1@gmail.com \ --cc=joe@perches.com \ --cc=jpoimboe@redhat.com \ --cc=linux-kernel-mentees@lists.linuxfoundation.org \ --cc=linux-kernel@vger.kernel.org \ --cc=lukas.bulwahn@gmail.com \ --cc=ndesaulniers@google.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.