Re: [PATCH 13/13] module: remove EXPORY_UNUSED_SYMBOL*

From: Jessica Yu
Date: Wed Jan 27 2021 - 08:52:24 EST


+++ Christoph Hellwig [21/01/21 08:49 +0100]:
EXPORT_UNUSED_SYMBOL* is not actually used anywhere. Remove the
unused functionality as we generally just remove unused code anyway.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/arm/configs/bcm2835_defconfig | 1 -
arch/arm/configs/mxs_defconfig | 1 -
arch/mips/configs/nlm_xlp_defconfig | 1 -
arch/mips/configs/nlm_xlr_defconfig | 1 -
arch/parisc/configs/generic-32bit_defconfig | 1 -
arch/parisc/configs/generic-64bit_defconfig | 1 -
arch/powerpc/configs/ppc6xx_defconfig | 1 -
arch/s390/configs/debug_defconfig | 1 -
arch/s390/configs/defconfig | 1 -
arch/sh/configs/edosk7760_defconfig | 1 -
arch/sh/configs/sdk7780_defconfig | 1 -
arch/x86/configs/i386_defconfig | 1 -
arch/x86/configs/x86_64_defconfig | 1 -
arch/x86/tools/relocs.c | 4 +-
include/asm-generic/vmlinux.lds.h | 28 ---------
include/linux/export.h | 8 ---
include/linux/module.h | 13 ----
init/Kconfig | 17 -----
kernel/module.c | 69 ++-------------------
scripts/checkpatch.pl | 6 +-
scripts/mod/modpost.c | 39 +-----------
scripts/mod/modpost.h | 2 -
scripts/module.lds.S | 4 --
tools/include/linux/export.h | 2 -
24 files changed, 13 insertions(+), 192 deletions(-)

diff --git a/arch/arm/configs/bcm2835_defconfig b/arch/arm/configs/bcm2835_defconfig
index 44ff9cd88d8161..d6c6c2e031c43a 100644
--- a/arch/arm/configs/bcm2835_defconfig
+++ b/arch/arm/configs/bcm2835_defconfig
@@ -177,7 +177,6 @@ CONFIG_BOOT_PRINTK_DELAY=y
CONFIG_DYNAMIC_DEBUG=y
CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_LOCKUP_DETECTOR=y
CONFIG_SCHED_TRACER=y
diff --git a/arch/arm/configs/mxs_defconfig b/arch/arm/configs/mxs_defconfig
index a9c6f32a9b1c9d..ca32446b187f5d 100644
--- a/arch/arm/configs/mxs_defconfig
+++ b/arch/arm/configs/mxs_defconfig
@@ -164,7 +164,6 @@ CONFIG_FONTS=y
CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
CONFIG_FRAME_WARN=2048
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_SOFTLOCKUP_DETECTOR=y
diff --git a/arch/mips/configs/nlm_xlp_defconfig b/arch/mips/configs/nlm_xlp_defconfig
index 72a211d2d556fd..32c29061172325 100644
--- a/arch/mips/configs/nlm_xlp_defconfig
+++ b/arch/mips/configs/nlm_xlp_defconfig
@@ -549,7 +549,6 @@ CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_FRAME_WARN=1024
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_DETECT_HUNG_TASK=y
CONFIG_SCHEDSTATS=y
diff --git a/arch/mips/configs/nlm_xlr_defconfig b/arch/mips/configs/nlm_xlr_defconfig
index 4ecb157e56d427..bf9b9244929ecd 100644
--- a/arch/mips/configs/nlm_xlr_defconfig
+++ b/arch/mips/configs/nlm_xlr_defconfig
@@ -500,7 +500,6 @@ CONFIG_CRC7=m
CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_DETECT_HUNG_TASK=y
CONFIG_SCHEDSTATS=y
diff --git a/arch/parisc/configs/generic-32bit_defconfig b/arch/parisc/configs/generic-32bit_defconfig
index 3cbcfad5f7249d..7611d48c599e01 100644
--- a/arch/parisc/configs/generic-32bit_defconfig
+++ b/arch/parisc/configs/generic-32bit_defconfig
@@ -22,7 +22,6 @@ CONFIG_PCI_LBA=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
-CONFIG_UNUSED_SYMBOLS=y
# CONFIG_BLK_DEV_BSG is not set
# CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is not set
CONFIG_BINFMT_MISC=m
diff --git a/arch/parisc/configs/generic-64bit_defconfig b/arch/parisc/configs/generic-64bit_defconfig
index 8f81fcbf04c413..53054b81461a10 100644
--- a/arch/parisc/configs/generic-64bit_defconfig
+++ b/arch/parisc/configs/generic-64bit_defconfig
@@ -31,7 +31,6 @@ CONFIG_MODULE_FORCE_LOAD=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_MODVERSIONS=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_BLK_DEV_INTEGRITY=y
CONFIG_BINFMT_MISC=m
# CONFIG_COMPACTION is not set
diff --git a/arch/powerpc/configs/ppc6xx_defconfig b/arch/powerpc/configs/ppc6xx_defconfig
index ef09f3cce1fa85..34c3859040f9f7 100644
--- a/arch/powerpc/configs/ppc6xx_defconfig
+++ b/arch/powerpc/configs/ppc6xx_defconfig
@@ -1072,7 +1072,6 @@ CONFIG_NLS_ISO8859_15=m
CONFIG_NLS_KOI8_R=m
CONFIG_NLS_KOI8_U=m
CONFIG_DEBUG_INFO=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_HEADERS_INSTALL=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index c4f6ff98a612cd..58e54d17e3154b 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -71,7 +71,6 @@ CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_MODVERSIONS=y
CONFIG_MODULE_SRCVERSION_ALL=y
CONFIG_MODULE_SIG_SHA256=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_BLK_DEV_INTEGRITY=y
CONFIG_BLK_DEV_THROTTLING=y
CONFIG_BLK_WBT=y
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 51135893cffe34..b5e62c0d3e23e0 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -66,7 +66,6 @@ CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_MODVERSIONS=y
CONFIG_MODULE_SRCVERSION_ALL=y
CONFIG_MODULE_SIG_SHA256=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_BLK_DEV_THROTTLING=y
CONFIG_BLK_WBT=y
CONFIG_BLK_CGROUP_IOLATENCY=y
diff --git a/arch/sh/configs/edosk7760_defconfig b/arch/sh/configs/edosk7760_defconfig
index 02ba622985769d..d77f54e906fd04 100644
--- a/arch/sh/configs/edosk7760_defconfig
+++ b/arch/sh/configs/edosk7760_defconfig
@@ -102,7 +102,6 @@ CONFIG_NLS_UTF8=y
CONFIG_PRINTK_TIME=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_MAGIC_SYSRQ=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_SHIRQ=y
CONFIG_DETECT_HUNG_TASK=y
diff --git a/arch/sh/configs/sdk7780_defconfig b/arch/sh/configs/sdk7780_defconfig
index d10a0414123a51..d53c4595fb2e98 100644
--- a/arch/sh/configs/sdk7780_defconfig
+++ b/arch/sh/configs/sdk7780_defconfig
@@ -130,7 +130,6 @@ CONFIG_NLS_ISO8859_15=y
CONFIG_NLS_UTF8=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_MAGIC_SYSRQ=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DETECT_HUNG_TASK=y
# CONFIG_SCHED_DEBUG is not set
diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig
index 78210793d357cf..9c9c4a888b1dbf 100644
--- a/arch/x86/configs/i386_defconfig
+++ b/arch/x86/configs/i386_defconfig
@@ -50,7 +50,6 @@ CONFIG_JUMP_LABEL=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
-# CONFIG_UNUSED_SYMBOLS is not set
CONFIG_BINFMT_MISC=y
CONFIG_NET=y
CONFIG_PACKET=y
diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig
index 9936528e19393a..b60bd2d8603499 100644
--- a/arch/x86/configs/x86_64_defconfig
+++ b/arch/x86/configs/x86_64_defconfig
@@ -48,7 +48,6 @@ CONFIG_JUMP_LABEL=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
-# CONFIG_UNUSED_SYMBOLS is not set
CONFIG_BINFMT_MISC=y
CONFIG_NET=y
CONFIG_PACKET=y
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 0d210d0e83e241..b9c577a3cacca6 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -61,8 +61,8 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"(__iommu_table|__apicdrivers|__smp_locks)(|_end)|"
"__(start|end)_pci_.*|"
"__(start|end)_builtin_fw|"
- "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl)|"
- "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl)|"
+ "__(start|stop)___ksymtab(|_gpl)|"
+ "__(start|stop)___kcrctab(|_gpl)|"
"__(start|stop)___param|"
"__(start|stop)___modver|"
"__(start|stop)___bug_table|"
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 83243506e68b00..1fa338ac6a5477 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -481,20 +481,6 @@
__stop___ksymtab_gpl = .; \
} \
\
- /* Kernel symbol table: Normal unused symbols */ \
- __ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \
- __start___ksymtab_unused = .; \
- KEEP(*(SORT(___ksymtab_unused+*))) \
- __stop___ksymtab_unused = .; \
- } \
- \
- /* Kernel symbol table: GPL-only unused symbols */ \
- __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
- __start___ksymtab_unused_gpl = .; \
- KEEP(*(SORT(___ksymtab_unused_gpl+*))) \
- __stop___ksymtab_unused_gpl = .; \
- } \
- \
/* Kernel symbol table: Normal symbols */ \
__kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \
__start___kcrctab = .; \
@@ -509,20 +495,6 @@
__stop___kcrctab_gpl = .; \
} \
\
- /* Kernel symbol table: Normal unused symbols */ \
- __kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \
- __start___kcrctab_unused = .; \
- KEEP(*(SORT(___kcrctab_unused+*))) \
- __stop___kcrctab_unused = .; \
- } \
- \
- /* Kernel symbol table: GPL-only unused symbols */ \
- __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
- __start___kcrctab_unused_gpl = .; \
- KEEP(*(SORT(___kcrctab_unused_gpl+*))) \
- __stop___kcrctab_unused_gpl = .; \
- } \
- \
/* Kernel symbol table: strings */ \
__ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
*(__ksymtab_strings) \
diff --git a/include/linux/export.h b/include/linux/export.h
index 362b64f8d4a7c2..6271a5d9c988fa 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -160,14 +160,6 @@ struct kernel_symbol {
#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", #ns)
#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "_gpl", #ns)

-#ifdef CONFIG_UNUSED_SYMBOLS
-#define EXPORT_UNUSED_SYMBOL(sym) _EXPORT_SYMBOL(sym, "_unused")
-#define EXPORT_UNUSED_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "_unused_gpl")
-#else
-#define EXPORT_UNUSED_SYMBOL(sym)
-#define EXPORT_UNUSED_SYMBOL_GPL(sym)
-#endif
-
#endif /* !__ASSEMBLY__ */

#endif /* _LINUX_EXPORT_H */
diff --git a/include/linux/module.h b/include/linux/module.h
index 8f4d577d4707c2..0e70596c9a704a 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -392,18 +392,6 @@ struct module {
const s32 *gpl_crcs;
bool using_gplonly_symbols;

-#ifdef CONFIG_UNUSED_SYMBOLS
- /* unused exported symbols. */
- const struct kernel_symbol *unused_syms;
- const s32 *unused_crcs;
- unsigned int num_unused_syms;
-
- /* GPL-only, unused exported symbols. */
- unsigned int num_unused_gpl_syms;
- const struct kernel_symbol *unused_gpl_syms;
- const s32 *unused_gpl_crcs;
-#endif
-
#ifdef CONFIG_MODULE_SIG
/* Signature was verified. */
bool sig_ok;
@@ -592,7 +580,6 @@ struct symsearch {
GPL_ONLY,
WILL_BE_GPL_ONLY,
} license;
- bool unused;
};

Thanks for the cleanups. While we're here, I noticed that struct
symsearch is only used internally in kernel/module.c, so I don't think
it actually needs to be in include/linux/module.h. I don't see it used
anywhere else. We could move maybe that to kernel/module-internal.h.