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From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: Nathan Chancellor <nathan@kernel.org>,
	Masahiro Yamada <masahiroy@kernel.org>,
	Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.15 45/76] modpost: Add '.ltext' and '.ltext.*' to TEXT_SECTIONS
Date: Wed, 13 Mar 2024 12:41:52 -0400
Message-ID: <20240313164223.615640-46-sashal@kernel.org>
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From: Nathan Chancellor <nathan@kernel.org>

[ Upstream commit 397586506c3da005b9333ce5947ad01e8018a3be ]

After the linked LLVM change, building ARCH=um defconfig results in a
segmentation fault in modpost. Prior to commit a23e7584ecf3 ("modpost:
unify 'sym' and 'to' in default_mismatch_handler()"), there was a
warning:

  WARNING: modpost: vmlinux.o(__ex_table+0x88): Section mismatch in reference to the .ltext:(unknown)
  WARNING: modpost: The relocation at __ex_table+0x88 references
  section ".ltext" which is not in the list of
  authorized sections.  If you're adding a new section
  and/or if this reference is valid, add ".ltext" to the
  list of authorized sections to jump to on fault.
  This can be achieved by adding ".ltext" to
  OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.

The linked LLVM change moves global objects to the '.ltext' (and
'.ltext.*' with '-ffunction-sections') sections with '-mcmodel=large',
which ARCH=um uses. These sections should be handled just as '.text'
and '.text.*' are, so add them to TEXT_SECTIONS.

Cc: stable@vger.kernel.org
Closes: https://github.com/ClangBuiltLinux/linux/issues/1981
Link: https://github.com/llvm/llvm-project/commit/4bf8a688956a759b7b6b8d94f42d25c13c7af130
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 scripts/mod/modpost.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 43bacdee5cc5d..201ac1bf5030d 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -937,7 +937,8 @@ static void check_section(const char *modname, struct elf_info *elf,
 
 #define DATA_SECTIONS ".data", ".data.rel"
 #define TEXT_SECTIONS ".text", ".text.*", ".sched.text", \
-		".kprobes.text", ".cpuidle.text", ".noinstr.text"
+		".kprobes.text", ".cpuidle.text", ".noinstr.text", \
+		".ltext", ".ltext.*"
 #define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
 		".fixup", ".entry.text", ".exception.text", \
 		".coldtext", ".softirqentry.text"
-- 
2.43.0