[4/4] modpost: remove .symbol_white_list field entirely

Commit Message

Masahiro Yamada Aug. 1, 2022, 9:39 a.m. UTC

It is not so useful to have symbol whitelists in arrays. With this
over-engineering, the code is difficult to follow.

Let's do it more directly, and collect the relevant code to one place.

Signed-off-by: Masahiro Yamada <[e-mail]>
---

 scripts/mod/modpost.c | 55 +++++++++++++------------------------------
 1 file changed, 16 insertions(+), 39 deletions(-)

Patch

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index bcd1319f3097..8484c0798f28 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -845,28 +845,12 @@  static const char *const init_data_sections[] =
 /* all init sections */
 static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
 
-/* All init and exit sections (code + data) */
-static const char *const init_exit_sections[] =
-	{ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
-
 /* all text sections */
 static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
 
 /* data section */
 static const char *const data_sections[] = { DATA_SECTIONS, NULL };
 
-
-/* symbols in .data that may refer to init/exit sections */
-#define DEFAULT_SYMBOL_WHITE_LIST					\
-	"*driver",							\
-	"*_template", /* scsi uses *_template a lot */			\
-	"*_timer",    /* arm uses ops structures named _timer a lot */	\
-	"*_sht",      /* scsi also used *_sht to some extent */		\
-	"*_ops",							\
-	"*_probe",							\
-	"*_probe_one",							\
-	"*_console"
-
 static const char *const head_sections[] = { ".head.text*", NULL };
 static const char *const linker_symbols[] =
 	{ "__init_begin", "_sinittext", "_einittext", NULL };
@@ -898,9 +882,6 @@  enum mismatch {
  *
  * @mismatch: Type of mismatch.
  *
- * @symbol_white_list: Do not match a relocation to a symbol in this list
- * even if it is targeting a section in @bad_to_sec.
- *
  * @handler: Specific handler to call when a match is found.  If NULL,
  * default_mismatch_handler() will be called.
  *
@@ -910,7 +891,6 @@  struct sectioncheck {
 	const char *bad_tosec[20];
 	const char *good_tosec[20];
 	enum mismatch mismatch;
-	const char *symbol_white_list[20];
 	void (*handler)(const char *modname, struct elf_info *elf,
 			const struct sectioncheck* const mismatch,
 			Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
@@ -935,16 +915,11 @@  static const struct sectioncheck sectioncheck[] = {
 	.fromsec = { DATA_SECTIONS, NULL },
 	.bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
 	.mismatch = DATA_TO_ANY_INIT,
-	.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
 },
 {
 	.fromsec = { DATA_SECTIONS, NULL },
 	.bad_tosec = { INIT_SECTIONS, NULL },
 	.mismatch = DATA_TO_ANY_INIT,
-	.symbol_white_list = {
-		"*_template", "*_timer", "*_sht", "*_ops",
-		"*_probe", "*_probe_one", "*_console", NULL
-	},
 },
 {
 	.fromsec = { TEXT_SECTIONS, NULL },
@@ -955,7 +930,6 @@  static const struct sectioncheck sectioncheck[] = {
 	.fromsec = { DATA_SECTIONS, NULL },
 	.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
 	.mismatch = DATA_TO_ANY_EXIT,
-	.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
 },
 /* Do not reference init code/data from meminit code/data */
 {
@@ -1051,15 +1025,6 @@  static const struct sectioncheck *section_mismatch(
  *   fromsec = .data*
  *   atsym   = __param_ops_*
  *
- * Pattern 2:
- *   Many drivers utilise a *driver container with references to
- *   add, remove, probe functions etc.
- *   the pattern is identified by:
- *   tosec   = init or exit section
- *   fromsec = data section
- *   atsym = *driver, *_template, *_sht, *_ops, *_probe,
- *           *probe_one, *_console, *_timer
- *
  * Pattern 3:
  *   Whitelist all references from .head.text to any init section
  *
@@ -1108,10 +1073,22 @@  static int secref_whitelist(const struct sectioncheck *mismatch,
 	    strstarts(fromsym, "__param_ops_"))
 		return 0;
 
-	/* Check for pattern 2 */
-	if (match(tosec, init_exit_sections) &&
-	    match(fromsec, data_sections) &&
-	    match(fromsym, mismatch->symbol_white_list))
+	/* 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("*_template", // scsi uses *_template a lot
+				    "*_timer", // arm uses ops structures named _timer a lot
+				    "*_sht", // scsi also used *_sht to some extent
+				    "*_ops",
+				    "*_probe",
+				    "*_probe_one",
+				    "*_console")))
+		return 0;
+
+	/* symbols in data sections that may refer to meminit/exit sections */
+	if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
+	    match(tosec, PATTERNS(ALL_XXXINIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
+	    match(fromsym, PATTERNS("*driver")))
 		return 0;
 
 	/* Check for pattern 3 */