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modpost: Ignore Clang LTO suffixes in symbol matching

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When building the kernel with Clang ThinLTO enabled, the compiler
can mangle static variable names by appending suffixes such as
".llvm.<hash>" to prevent naming collisions across translation units.

This name mangling breaks the section mismatch whitelisting in modpost.
modpost relies on glob patterns (e.g., "*_ops" or "*_probe") to identify
safe references between permanent data and initialization code. Because
the LTO suffix modifies the end of the symbol name, legitimately
whitelisted structures fail the match, resulting in false positive
warnings.

For example, a static pernet_operations struct triggers the following:

  WARNING: modpost: vmlinux: section mismatch in reference: \
  ping_v4_net_ops.llvm.5641696707737373282 (section: .data) -> \
  ping_v4_proc_init_net (section: .init.text)

Fix this by ignoring "*_ops.llvm.*" in "from" symbol names (the same
as "*_ops").

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202606111233.kM8oo8Df-lkp@intel.com/
Signed-off-by: Rong Xu <xur@google.com>
Link: https://patch.msgid.link/20260617224623.1346309-1-xur@google.com
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
This commit is contained in:
Rong Xu
2026-06-17 15:46:23 -07:00
committed by Nathan Chancellor
parent 7158c5b67e
commit 9a289cc425
1 changed files with 1 additions and 1 deletions
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scripts/mod/modpost.c
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@@ -969,7 +969,7 @@ static int secref_whitelist(const char *fromsec, const char *fromsym,
/* symbols in data sections that may refer to any init/exit sections */
if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
match(fromsym, PATTERNS("*_ops", "*_console")))
match(fromsym, PATTERNS("*_ops", "*_ops.llvm.*", "*_console")))
return 0;
/* Check for pattern 3 */