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tracing: Exit with error if a weak function is used in recordmcount.pl

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If a weak function is used as a relocation reference for mcount callers
and that function is overridden, it will cause ftrace to fail at run time.

The current code should prevent a weak function from being used, but if
one is, the code should exit with an error to fail at compile time.

Signed-off-by: Li Hong <lihong.hi@gmail.com>
LKML-Reference: <20091028050743.GH30758@uhli>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Li Hong 2009-10-28 13:07:43 +08:00 committed by Steven Rostedt
parent 6092858c60
commit c4b8ac2c1a
1 changed files with 3 additions and 7 deletions
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10
scripts/recordmcount.pl
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@ -350,15 +350,11 @@ sub update_funcs
{
return unless ($ref_func and @offsets);
# A section only had a weak function, to represent it.
# Unfortunately, a weak function may be overwritten by another
# function of the same name, making all these offsets incorrect.
# To be safe, we simply print a warning and bail.
# Sanity check on weak function. A weak function may be overwritten by
# another function of the same name, making all these offsets incorrect.
if (defined $weak{$ref_func}) {
print STDERR
"$inputfile: WARNING: referencing weak function" .
die "$inputfile: ERROR: referencing weak function" .
" $ref_func for mcount\n";
return;
}
# is this function static? If so, note this fact.