[PATCH 16/33] kbuild: refactor code in modpost to improve maintainability

Sam Ravnborg
2007-07-17T14:12:23Z

There were a great deal of overlap between the two functions
that check which sections may reference .init.text and .exit.text.
Factor out common check to a separate function and
sort entries in the original functions.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
---
scripts/mod/modpost.c | 154 ++++++++++++++++++++++++-------------------------
1 files changed, 75 insertions(+), 79 deletions(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 9c35f30..f22c8b4 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -858,14 +858,6 @@ static void warn_sec_mismatch(const char *modname, const char *fromsec,
elf->strtab + before->st_name, refsymname))
return;

- /* fromsec whitelist - without a valid 'before'
- * powerpc has a GOT table in .got2 section
- * and also a .toc section */
- if (strcmp(fromsec, ".got2") == 0)
- return;
- if (strcmp(fromsec, ".toc") == 0)
- return;
-
if (before && after) {
warn("%s(%s+0x%llx): Section mismatch: reference to %s:%s "
"(between '%s' and '%s')\n",
@@ -1087,6 +1079,61 @@ static void check_sec_ref(struct module *mod, const char *modname,
}
}

+/*
+ * Identify sections from which references to either a
+ * .init or a .exit section is OK.
+ *
+ * [OPD] Keith Ownes <kaos@sgi.com> commented:
+ * For our future {in}sanity, add a comment that this is the ppc .opd
+ * section, not the ia64 .opd section.
+ * ia64 .opd should not point to discarded sections.
+ * [.rodata] like for .init.text we ignore .rodata references -same reason
+ **/
+static int initexit_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ "__bug_table", /* used by powerpc for BUG() */
+ "__ex_table",
+ ".altinstructions",
+ ".cranges", /* used by sh64 */
+ ".fixup",
+ ".opd", /* See comment [OPD] */
+ ".parainstructions",
+ ".pdr",
+ ".plt", /* seen on ARCH=um build on x86_64. Harmless */
+ ".smp_locks",
+ ".stab",
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".debug",
+ ".eh_frame",
+ ".note", /* ignore ELF notes - may contain anything */
+ ".got", /* powerpc - global offset table */
+ ".toc", /* powerpc - table of contents */
+ NULL
+ };
+ /* part of section name */
+ const char *namelist3 [] = {
+ ".unwind", /* Sample: IA_64.unwind.exit.text */
+ NULL
+ };
+
+ for (s = namelist1; *s; s++)
+ if (strcmp(*s, name) == 0)
+ return 1;
+ for (s = namelist2; *s; s++)
+ if (strncmp(*s, name, strlen(*s)) == 0)
+ return 1;
+ for (s = namelist3; *s; s++)
+ if (strstr(name, *s) != NULL)
+ return 1;
+ return 0;
+}
+
/**
* Functions used only during module init is marked __init and is stored in
* a .init.text section. Likewise data is marked __initdata and stored in
@@ -1103,7 +1150,7 @@ static int init_section(const char *name)
return 0;
}

-/**
+/*
* Identify sections from which references to a .init section is OK.
*
* Unfortunately references to read only data that referenced .init
@@ -1117,59 +1164,41 @@ static int init_section(const char *name)
*
* where vgacon_startup is __init. If you want to wade through the false
* positives, take out the check for rodata.
- **/
+ */
static int init_section_ref_ok(const char *name)
{
const char **s;
/* Absolute section names */
const char *namelist1[] = {
- ".init",
- ".opd", /* see comment [OPD] at exit_section_ref_ok() */
- ".toc1", /* used by ppc64 */
- ".stab",
- ".data.rel.ro", /* used by parisc64 */
- ".parainstructions",
- ".text.lock",
- "__bug_table", /* used by powerpc for BUG() */
- ".pci_fixup_header",
- ".pci_fixup_final",
- ".pdr",
- "__param",
- "__ex_table",
- ".fixup",
- ".smp_locks",
- ".plt", /* seen on ARCH=um build on x86_64. Harmless */
"__ftr_fixup", /* powerpc cpu feature fixup */
"__fw_ftr_fixup", /* powerpc firmware feature fixup */
- ".cranges", /* used by sh64 */
+ "__param",
+ ".data.rel.ro", /* used by parisc64 */
+ ".init",
+ ".text.lock",
NULL
};
/* Start of section names */
const char *namelist2[] = {
".init.",
- ".altinstructions",
- ".eh_frame",
- ".debug",
- ".parainstructions",
+ ".pci_fixup",
".rodata",
- ".note", /* ignore ELF notes - may contain anything */
- NULL
- };
- /* part of section name */
- const char *namelist3 [] = {
- ".unwind", /* sample: IA_64.unwind.init.text */
NULL
};

+ if (initexit_section_ref_ok(name))
+ return 1;
+
for (s = namelist1; *s; s++)
if (strcmp(*s, name) == 0)
return 1;
for (s = namelist2; *s; s++)
if (strncmp(*s, name, strlen(*s)) == 0)
return 1;
- for (s = namelist3; *s; s++)
- if (strstr(name, *s) != NULL)
- return 1;
+
+ /* If section name ends with ".init" we allow references
+ * as is the case with .initcallN.init, .early_param.init, .taglist.init etc
+ */
if (strrcmp(name, ".init") == 0)
return 1;
return 0;
@@ -1194,59 +1223,26 @@ static int exit_section(const char *name)

/*
* Identify sections from which references to a .exit section is OK.
- *
- * [OPD] Keith Ownes <kaos@sgi.com> commented:
- * For our future {in}sanity, add a comment that this is the ppc .opd
- * section, not the ia64 .opd section.
- * ia64 .opd should not point to discarded sections.
- * [.rodata] like for .init.text we ignore .rodata references -same reason
- **/
+ */
static int exit_section_ref_ok(const char *name)
{
const char **s;
/* Absolute section names */
const char *namelist1[] = {
- ".exit.text",
".exit.data",
+ ".exit.text",
+ ".exitcall.exit",
".init.text",
".rodata",
- ".opd", /* See comment [OPD] */
- ".toc1", /* used by ppc64 */
- ".altinstructions",
- ".pdr",
- "__bug_table", /* used by powerpc for BUG() */
- ".exitcall.exit",
- ".eh_frame",
- ".parainstructions",
- ".stab",
- "__ex_table",
- ".fixup",
- ".smp_locks",
- ".plt", /* seen on ARCH=um build on x86_64. Harmless */
- ".cranges", /* used by sh64 */
- NULL
- };
- /* Start of section names */
- const char *namelist2[] = {
- ".debug",
- ".note", /* ignore ELF notes - may contain anything */
- NULL
- };
- /* part of section name */
- const char *namelist3 [] = {
- ".unwind", /* Sample: IA_64.unwind.exit.text */
NULL
};

+ if (initexit_section_ref_ok(name))
+ return 1;
+
for (s = namelist1; *s; s++)
if (strcmp(*s, name) == 0)
return 1;
- for (s = namelist2; *s; s++)
- if (strncmp(*s, name, strlen(*s)) == 0)
- return 1;
- for (s = namelist3; *s; s++)
- if (strstr(name, *s) != NULL)
- return 1;
return 0;
}

--
1.5.0.6