23 files changed, 201 insertions, 139 deletions

diff --git a/Makefile b/Makefile
index 4572f106e30b..878d7aa3d2dd 100644
--- a/Makefile
+++ b/Makefile
@@ -1399,7 +1399,7 @@ quiet_cmd_rmfiles = $(if $(wildcard $(rm-files)),CLEAN   $(wildcard $(rm-files))
 # Run depmod only if we have System.map and depmod is executable
 quiet_cmd_depmod = DEPMOD  $(KERNELRELEASE)
       cmd_depmod = $(CONFIG_SHELL) $(srctree)/scripts/depmod.sh $(DEPMOD) \
-                   $(KERNELRELEASE) "$(patsubst "%",%,$(CONFIG_SYMBOL_PREFIX))"
+                   $(KERNELRELEASE) "$(patsubst y,_,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))"
 
 # Create temporary dir for module support files
 # clean it up only when building all modules
diff --git a/arch/Kconfig b/arch/Kconfig
index 99f0e17df429..dd0e8eb8042f 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -381,6 +381,12 @@ config MODULES_USE_ELF_REL
           Modules only use ELF REL relocations.  Modules with ELF RELA
           relocations will give an error.
 
+config HAVE_UNDERSCORE_SYMBOL_PREFIX
+        bool
+        help
+          Some architectures generate an _ in front of C symbols; things like
+          module loading and assembly files need to know about this.
+
 #
 # ABI hall of shame
 #
diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index c3f2e0bc644a..453ebe46b065 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -1,7 +1,3 @@
-config SYMBOL_PREFIX
-        string
-        default "_"
-
 config MMU
         def_bool n
 
@@ -33,6 +29,7 @@ config BLACKFIN
         select ARCH_HAVE_CUSTOM_GPIO_H
         select ARCH_WANT_OPTIONAL_GPIOLIB
         select HAVE_UID16
+        select HAVE_UNDERSCORE_SYMBOL_PREFIX
         select VIRT_TO_BUS
         select ARCH_WANT_IPC_PARSE_VERSION
         select HAVE_GENERIC_HARDIRQS
diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
index 79250de1b12a..303e4f9a79d1 100644
--- a/arch/h8300/Kconfig
+++ b/arch/h8300/Kconfig
@@ -12,10 +12,7 @@ config H8300
         select MODULES_USE_ELF_RELA
         select OLD_SIGSUSPEND3
         select OLD_SIGACTION
-
-config SYMBOL_PREFIX
-        string
-        default "_"
+        select HAVE_UNDERSCORE_SYMBOL_PREFIX
 
 config MMU
         bool
diff --git a/arch/metag/Kconfig b/arch/metag/Kconfig
index b06b41861aac..6f16c1469327 100644
--- a/arch/metag/Kconfig
+++ b/arch/metag/Kconfig
@@ -1,7 +1,3 @@
-config SYMBOL_PREFIX
-        string
-        default "_"
-
 config METAG
         def_bool y
         select EMBEDDED
@@ -28,6 +24,7 @@ config METAG
         select HAVE_OPROFILE
         select HAVE_PERF_EVENTS
         select HAVE_SYSCALL_TRACEPOINTS
+        select HAVE_UNDERSCORE_SYMBOL_PREFIX
         select IRQ_DOMAIN
         select MODULES_USE_ELF_RELA
         select OF
diff --git a/crypto/asymmetric_keys/x509_cert_parser.c b/crypto/asymmetric_keys/x509_cert_parser.c
index 7fabc4c01993..facbf26bc6bb 100644
--- a/crypto/asymmetric_keys/x509_cert_parser.c
+++ b/crypto/asymmetric_keys/x509_cert_parser.c
@@ -373,6 +373,9 @@ int rsa_extract_mpi(void *context, size_t hdrlen,
         return 0;
 }
 
+/* The keyIdentifier in AuthorityKeyIdentifier SEQUENCE is tag(CONT,PRIM,0) */
+#define SEQ_TAG_KEYID (ASN1_CONT << 6)
+
 /*
  * Process certificate extensions that are used to qualify the certificate.
  */
@@ -407,21 +410,57 @@ int x509_process_extension(void *context, size_t hdrlen,
         }
 
         if (ctx->last_oid == OID_authorityKeyIdentifier) {
+                size_t key_len;
+
                 /* Get hold of the CA key fingerprint */
                 if (vlen < 5)
                         return -EBADMSG;
-                if (v[0] != (ASN1_SEQ | (ASN1_CONS << 5)) ||
-                    v[1] != vlen - 2 ||
-                    v[2] != (ASN1_CONT << 6) ||
-                    v[3] != vlen - 4)
+
+                /* Authority Key Identifier must be a Constructed SEQUENCE */
+                if (v[0] != (ASN1_SEQ | (ASN1_CONS << 5)))
                         return -EBADMSG;
-                v += 4;
-                vlen -= 4;
 
-                f = kmalloc(vlen * 2 + 1, GFP_KERNEL);
+                /* Authority Key Identifier is not indefinite length */
+                if (unlikely(vlen == ASN1_INDEFINITE_LENGTH))
+                        return -EBADMSG;
+
+                if (vlen < ASN1_INDEFINITE_LENGTH) {
+                        /* Short Form length */
+                        if (v[1] != vlen - 2 ||
+                            v[2] != SEQ_TAG_KEYID ||
+                            v[3] > vlen - 4)
+                                return -EBADMSG;
+
+                        key_len = v[3];
+                        v += 4;
+                } else {
+                        /* Long Form length */
+                        size_t seq_len = 0;
+                        size_t sub = v[1] - ASN1_INDEFINITE_LENGTH;
+
+                        if (sub > 2)
+                                return -EBADMSG;
+
+                        /* calculate the length from subsequent octets */
+                        v += 2;
+                        for (i = 0; i < sub; i++) {
+                                seq_len <<= 8;
+                                seq_len |= v[i];
+                        }
+
+                        if (seq_len != vlen - 2 - sub ||
+                            v[sub] != SEQ_TAG_KEYID ||
+                            v[sub + 1] > vlen - 4 - sub)
+                                return -EBADMSG;
+
+                        key_len = v[sub + 1];
+                        v += (sub + 2);
+                }
+
+                f = kmalloc(key_len * 2 + 1, GFP_KERNEL);
                 if (!f)
                         return -ENOMEM;
-                for (i = 0; i < vlen; i++)
+                for (i = 0; i < key_len; i++)
                         sprintf(f + i * 2, "%02x", v[i]);
                 pr_debug("authority   %s\n", f);
                 ctx->cert->authority = f;
diff --git a/drivers/mtd/chips/gen_probe.c b/drivers/mtd/chips/gen_probe.c
index 3b9a2843c5f8..74dbb6bcf488 100644
--- a/drivers/mtd/chips/gen_probe.c
+++ b/drivers/mtd/chips/gen_probe.c
@@ -204,14 +204,16 @@ static inline struct mtd_info *cfi_cmdset_unknown(struct map_info *map,
         struct cfi_private *cfi = map->fldrv_priv;
         __u16 type = primary?cfi->cfiq->P_ID:cfi->cfiq->A_ID;
 #ifdef CONFIG_MODULES
-        char probename[16+sizeof(MODULE_SYMBOL_PREFIX)];
+        char probename[sizeof(VMLINUX_SYMBOL_STR(cfi_cmdset_%4.4X))];
         cfi_cmdset_fn_t *probe_function;
 
-        sprintf(probename, MODULE_SYMBOL_PREFIX "cfi_cmdset_%4.4X", type);
+        sprintf(probename, VMLINUX_SYMBOL_STR(cfi_cmdset_%4.4X), type);
 
         probe_function = __symbol_get(probename);
         if (!probe_function) {
-                request_module(probename + sizeof(MODULE_SYMBOL_PREFIX) - 1);
+                char modname[sizeof("cfi_cmdset_%4.4X")];
+                sprintf(modname, "cfi_cmdset_%4.4X", type);
+                request_module(modname);
                 probe_function = __symbol_get(probename);
         }
 
diff --git a/include/asm-generic/unistd.h b/include/asm-generic/unistd.h
index 0501fa3f783d..cccc86ecfeaa 100644
--- a/include/asm-generic/unistd.h
+++ b/include/asm-generic/unistd.h
@@ -1,4 +1,5 @@
 #include <uapi/asm-generic/unistd.h>
+#include <linux/export.h>
 
 /*
  * These are required system calls, we should
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index afa12c7a025c..eb58d2d7d971 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -52,13 +52,7 @@
 #define LOAD_OFFSET 0
 #endif
 
-#ifndef SYMBOL_PREFIX
-#define VMLINUX_SYMBOL(sym) sym
-#else
-#define PASTE2(x,y) x##y
-#define PASTE(x,y) PASTE2(x,y)
-#define VMLINUX_SYMBOL(sym) PASTE(SYMBOL_PREFIX, sym)
-#endif
+#include <linux/export.h>
 
 /* Align . to a 8 byte boundary equals to maximum function alignment. */
 #define ALIGN_FUNCTION()  . = ALIGN(8)
diff --git a/include/linux/export.h b/include/linux/export.h
index 696c0f48afc7..412cd509effe 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -5,17 +5,24 @@
  * to reduce the amount of pointless cruft we feed to gcc when only
  * exporting a simple symbol or two.
  *
- * If you feel the need to add #include <linux/foo.h> to this file
- * then you are doing something wrong and should go away silently.
+ * Try not to add #includes here.  It slows compilation and makes kernel
+ * hackers place grumpy comments in header files.
  */
 
 /* Some toolchains use a `_' prefix for all user symbols. */
-#ifdef CONFIG_SYMBOL_PREFIX
-#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
+#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
+#define __VMLINUX_SYMBOL(x) _##x
+#define __VMLINUX_SYMBOL_STR(x) "_" #x
 #else
-#define MODULE_SYMBOL_PREFIX ""
+#define __VMLINUX_SYMBOL(x) x
+#define __VMLINUX_SYMBOL_STR(x) #x
 #endif
 
+/* Indirect, so macros are expanded before pasting. */
+#define VMLINUX_SYMBOL(x) __VMLINUX_SYMBOL(x)
+#define VMLINUX_SYMBOL_STR(x) __VMLINUX_SYMBOL_STR(x)
+
+#ifndef __ASSEMBLY__
 struct kernel_symbol
 {
         unsigned long value;
@@ -51,7 +58,7 @@ extern struct module __this_module;
         __CRC_SYMBOL(sym, sec)                                  \
         static const char __kstrtab_##sym[]                     \
         __attribute__((section("__ksymtab_strings"), aligned(1))) \
-        = MODULE_SYMBOL_PREFIX #sym;                            \
+        = VMLINUX_SYMBOL_STR(sym);                              \
         static const struct kernel_symbol __ksymtab_##sym       \
         __used                                                  \
         __attribute__((section("___ksymtab" sec "+" #sym), unused))     \
@@ -85,5 +92,6 @@ extern struct module __this_module;
 #define EXPORT_UNUSED_SYMBOL_GPL(sym)
 
 #endif /* CONFIG_MODULES */
+#endif /* !__ASSEMBLY__ */
 
 #endif /* _LINUX_EXPORT_H */
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 6d1844f393c0..e96329ceb28c 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -786,13 +786,6 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
 /* Trap pasters of __FUNCTION__ at compile-time */
 #define __FUNCTION__ (__func__)
 
-/* This helps us to avoid #ifdef CONFIG_SYMBOL_PREFIX */
-#ifdef CONFIG_SYMBOL_PREFIX
-#define SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
-#else
-#define SYMBOL_PREFIX ""
-#endif
-
 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
diff --git a/include/linux/linkage.h b/include/linux/linkage.h
index de09dec25ec3..d3e8ad23a8e0 100644
--- a/include/linux/linkage.h
+++ b/include/linux/linkage.h
@@ -3,6 +3,7 @@
 
 #include <linux/compiler.h>
 #include <linux/stringify.h>
+#include <linux/export.h>
 #include <asm/linkage.h>
 
 #ifdef __cplusplus
@@ -15,21 +16,18 @@
 #define asmlinkage CPP_ASMLINKAGE
 #endif
 
-#ifdef CONFIG_SYMBOL_PREFIX
-#define __SYMBOL_NAME(x) CONFIG_SYMBOL_PREFIX __stringify(x)
-#else
-#define __SYMBOL_NAME(x) __stringify(x)
-#endif
-
 #ifndef cond_syscall
-#define cond_syscall(x) asm(".weak\t" __SYMBOL_NAME(x) \
-        "\n\t.set\t" __SYMBOL_NAME(x) "," __SYMBOL_NAME(sys_ni_syscall));
+#define cond_syscall(x) asm(                            \
+        ".weak " VMLINUX_SYMBOL_STR(x) "\n\t"           \
+        ".set  " VMLINUX_SYMBOL_STR(x) ","              \
+                 VMLINUX_SYMBOL_STR(sys_ni_syscall))
 #endif
 
 #ifndef SYSCALL_ALIAS
-#define SYSCALL_ALIAS(alias, name)                              \
-        asm ("\t.globl " __SYMBOL_NAME(alias)                   \
-        "\n\t.set\t" __SYMBOL_NAME(alias) "," __SYMBOL_NAME(name))
+#define SYSCALL_ALIAS(alias, name) asm(                 \
+        ".globl " VMLINUX_SYMBOL_STR(alias) "\n\t"      \
+        ".set   " VMLINUX_SYMBOL_STR(alias) ","         \
+                  VMLINUX_SYMBOL_STR(name))
 #endif
 
 #define __page_aligned_data     __section(.data..page_aligned) __aligned(PAGE_SIZE)
diff --git a/include/linux/module.h b/include/linux/module.h
index ead1b5719a12..46f1ea01e6f6 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -190,7 +190,7 @@ extern int modules_disabled; /* for sysctl */
 /* Get/put a kernel symbol (calls must be symmetric) */
 void *__symbol_get(const char *symbol);
 void *__symbol_get_gpl(const char *symbol);
-#define symbol_get(x) ((typeof(&x))(__symbol_get(MODULE_SYMBOL_PREFIX #x)))
+#define symbol_get(x) ((typeof(&x))(__symbol_get(VMLINUX_SYMBOL_STR(x))))
 
 /* modules using other modules: kdb wants to see this. */
 struct module_use {
@@ -453,7 +453,7 @@ extern void __module_put_and_exit(struct module *mod, long code)
 #ifdef CONFIG_MODULE_UNLOAD
 unsigned long module_refcount(struct module *mod);
 void __symbol_put(const char *symbol);
-#define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x)
+#define symbol_put(x) __symbol_put(VMLINUX_SYMBOL_STR(x))
 void symbol_put_addr(void *addr);
 
 /* Sometimes we know we already have a refcount, and it's easier not
diff --git a/kernel/Makefile b/kernel/Makefile
index d1574d47cf27..271fd3119af9 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -176,7 +176,7 @@ signing_key.priv signing_key.x509: x509.genkey
         openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_HASH) -days 36500 \
                 -batch -x509 -config x509.genkey \
                 -outform DER -out signing_key.x509 \
-                -keyout signing_key.priv
+                -keyout signing_key.priv 2>&1
         @echo "###"
         @echo "### Key pair generated."
         @echo "###"
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 2169feeba529..3127ad52cdb2 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -84,9 +84,11 @@ static int is_ksym_addr(unsigned long addr)
 
 /*
  * Expand a compressed symbol data into the resulting uncompressed string,
+ * if uncompressed string is too long (>= maxlen), it will be truncated,
  * given the offset to where the symbol is in the compressed stream.
  */
-static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
+static unsigned int kallsyms_expand_symbol(unsigned int off,
+                                           char *result, size_t maxlen)
 {
         int len, skipped_first = 0;
         const u8 *tptr, *data;
@@ -113,15 +115,20 @@ static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
 
                 while (*tptr) {
                         if (skipped_first) {
+                                if (maxlen <= 1)
+                                        goto tail;
                                 *result = *tptr;
                                 result++;
+                                maxlen--;
                         } else
                                 skipped_first = 1;
                         tptr++;
                 }
         }
 
-        *result = '\0';
+tail:
+        if (maxlen)
+                *result = '\0';
 
         /* Return to offset to the next symbol. */
         return off;
@@ -176,7 +183,7 @@ unsigned long kallsyms_lookup_name(const char *name)
         unsigned int off;
 
         for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
-                off = kallsyms_expand_symbol(off, namebuf);
+                off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf));
 
                 if (strcmp(namebuf, name) == 0)
                         return kallsyms_addresses[i];
@@ -195,7 +202,7 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
         int ret;
 
         for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
-                off = kallsyms_expand_symbol(off, namebuf);
+                off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf));
                 ret = fn(data, namebuf, NULL, kallsyms_addresses[i]);
                 if (ret != 0)
                         return ret;
@@ -294,7 +301,8 @@ const char *kallsyms_lookup(unsigned long addr,
 
                 pos = get_symbol_pos(addr, symbolsize, offset);
                 /* Grab name */
-                kallsyms_expand_symbol(get_symbol_offset(pos), namebuf);
+                kallsyms_expand_symbol(get_symbol_offset(pos),
+                                       namebuf, KSYM_NAME_LEN);
                 if (modname)
                         *modname = NULL;
                 return namebuf;
@@ -315,7 +323,8 @@ int lookup_symbol_name(unsigned long addr, char *symname)
 
                 pos = get_symbol_pos(addr, NULL, NULL);
                 /* Grab name */
-                kallsyms_expand_symbol(get_symbol_offset(pos), symname);
+                kallsyms_expand_symbol(get_symbol_offset(pos),
+                                       symname, KSYM_NAME_LEN);
                 return 0;
         }
         /* See if it's in a module. */
@@ -333,7 +342,8 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size,
 
                 pos = get_symbol_pos(addr, size, offset);
                 /* Grab name */
-                kallsyms_expand_symbol(get_symbol_offset(pos), name);
+                kallsyms_expand_symbol(get_symbol_offset(pos),
+                                       name, KSYM_NAME_LEN);
                 modname[0] = '\0';
                 return 0;
         }
@@ -463,7 +473,7 @@ static unsigned long get_ksymbol_core(struct kallsym_iter *iter)
 
         iter->type = kallsyms_get_symbol_type(off);
 
-        off = kallsyms_expand_symbol(off, iter->name);
+        off = kallsyms_expand_symbol(off, iter->name, ARRAY_SIZE(iter->name));
 
         return off - iter->nameoff;
 }
diff --git a/kernel/modsign_certificate.S b/kernel/modsign_certificate.S
index 246b4c6e6135..4a9a86d12c8b 100644
--- a/kernel/modsign_certificate.S
+++ b/kernel/modsign_certificate.S
@@ -1,15 +1,8 @@
-/* SYMBOL_PREFIX defined on commandline from CONFIG_SYMBOL_PREFIX */
-#ifndef SYMBOL_PREFIX
-#define ASM_SYMBOL(sym) sym
-#else
-#define PASTE2(x,y) x##y
-#define PASTE(x,y) PASTE2(x,y)
-#define ASM_SYMBOL(sym) PASTE(SYMBOL_PREFIX, sym)
-#endif
+#include <linux/export.h>
 
 #define GLOBAL(name)    \
-        .globl ASM_SYMBOL(name);        \
-        ASM_SYMBOL(name):
+        .globl VMLINUX_SYMBOL(name);    \
+        VMLINUX_SYMBOL(name):
 
         .section ".init.data","aw"
 
diff --git a/kernel/module.c b/kernel/module.c
index 0925c9a71975..b049939177f6 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1209,10 +1209,11 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
 
         /* Since this should be found in kernel (which can't be removed),
          * no locking is necessary. */
-        if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
+        if (!find_symbol(VMLINUX_SYMBOL_STR(module_layout), NULL,
                          &crc, true, false))
                 BUG();
-        return check_version(sechdrs, versindex, "module_layout", mod, crc,
+        return check_version(sechdrs, versindex,
+                             VMLINUX_SYMBOL_STR(module_layout), mod, crc,
                              NULL);
 }
 
@@ -1861,12 +1862,12 @@ static void free_module(struct module *mod)
 {
         trace_module_free(mod);
 
-        /* Delete from various lists */
-        mutex_lock(&module_mutex);
-        stop_machine(__unlink_module, mod, NULL);
-        mutex_unlock(&module_mutex);
         mod_sysfs_teardown(mod);
 
+        /* We leave it in list to prevent duplicate loads, but make sure
+         * that noone uses it while it's being deconstructed. */
+        mod->state = MODULE_STATE_UNFORMED;
+
         /* Remove dynamic debug info */
         ddebug_remove_module(mod->name);
 
@@ -1879,6 +1880,11 @@ static void free_module(struct module *mod)
         /* Free any allocated parameters. */
         destroy_params(mod->kp, mod->num_kp);
 
+        /* Now we can delete it from the lists */
+        mutex_lock(&module_mutex);
+        stop_machine(__unlink_module, mod, NULL);
+        mutex_unlock(&module_mutex);
+
         /* This may be NULL, but that's OK */
         unset_module_init_ro_nx(mod);
         module_free(mod, mod->module_init);
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 0e801c3cdaf8..d5d859c80729 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -211,7 +211,8 @@ $(obj)/%.i: $(src)/%.c FORCE
 
 cmd_gensymtypes =                                                           \
     $(CPP) -D__GENKSYMS__ $(c_flags) $< |                                   \
-    $(GENKSYMS) $(if $(1), -T $(2)) -a $(ARCH)                              \
+    $(GENKSYMS) $(if $(1), -T $(2))                                         \
+     $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX))             \
      $(if $(KBUILD_PRESERVE),-p)                                            \
      -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
 
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3e73dfd838cd..51bb3de680b6 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -119,13 +119,6 @@ _c_flags += $(if $(patsubst n%,, \
                 $(CFLAGS_GCOV))
 endif
 
-ifdef CONFIG_SYMBOL_PREFIX
-_sym_flags = -DSYMBOL_PREFIX=$(patsubst "%",%,$(CONFIG_SYMBOL_PREFIX))
-_cpp_flags += $(_sym_flags)
-_a_flags += $(_sym_flags)
-endif
-
-
 # If building the kernel in a separate objtree expand all occurrences
 # of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').
 
diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost
index cf82c832458f..8dcdca27d836 100644
--- a/scripts/Makefile.modpost
+++ b/scripts/Makefile.modpost
@@ -60,7 +60,8 @@ kernelsymfile := $(objtree)/Module.symvers
 modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers
 
 # Step 1), find all modules listed in $(MODVERDIR)/
-__modules := $(sort $(shell grep -h '\.ko$$' /dev/null $(wildcard $(MODVERDIR)/*.mod)))
+MODLISTCMD := find $(MODVERDIR) -name '*.mod' | xargs -r grep -h '\.ko$$' | sort -u
+__modules := $(shell $(MODLISTCMD))
 modules   := $(patsubst %.o,%.ko, $(wildcard $(__modules:.ko=.o)))
 
 # Stop after building .o files if NOFINAL is set. Makes compile tests quicker
@@ -78,12 +79,13 @@ modpost = scripts/mod/modpost                    \
  $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S)      \
  $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w)
 
+# We can go over command line length here, so be careful.
 quiet_cmd_modpost = MODPOST $(words $(filter-out vmlinux FORCE, $^)) modules
-      cmd_modpost = $(modpost) -s
+      cmd_modpost = $(MODLISTCMD) | sed 's/\.ko$$/.o/' | $(modpost) -s -T -
 
 PHONY += __modpost
 __modpost: $(modules:.ko=.o) FORCE
-        $(call cmd,modpost) $(wildcard vmlinux) $(filter-out FORCE,$^)
+        $(call cmd,modpost) $(wildcard vmlinux)
 
 quiet_cmd_kernel-mod = MODPOST $@
       cmd_kernel-mod = $(modpost) $@
diff --git a/scripts/genksyms/genksyms.c b/scripts/genksyms/genksyms.c
index d25e4a118d37..88632df4381b 100644
--- a/scripts/genksyms/genksyms.c
+++ b/scripts/genksyms/genksyms.c
@@ -45,7 +45,6 @@ int in_source_file;
 
 static int flag_debug, flag_dump_defs, flag_reference, flag_dump_types,
            flag_preserve, flag_warnings;
-static const char *arch = "";
 static const char *mod_prefix = "";
 
 static int errors;
@@ -731,7 +730,7 @@ static void genksyms_usage(void)
 {
         fputs("Usage:\n" "genksyms [-adDTwqhV] > /path/to/.tmp_obj.ver\n" "\n"
 #ifdef __GNU_LIBRARY__
-              "  -a, --arch            Select architecture\n"
+              "  -s, --symbol-prefix   Select symbol prefix\n"
               "  -d, --debug           Increment the debug level (repeatable)\n"
               "  -D, --dump            Dump expanded symbol defs (for debugging only)\n"
               "  -r, --reference file  Read reference symbols from a file\n"
@@ -742,7 +741,7 @@ static void genksyms_usage(void)
               "  -h, --help            Print this message\n"
               "  -V, --version         Print the release version\n"
 #else                           /* __GNU_LIBRARY__ */
-              "  -a                    Select architecture\n"
+              "  -s                    Select symbol prefix\n"
               "  -d                    Increment the debug level (repeatable)\n"
               "  -D                    Dump expanded symbol defs (for debugging only)\n"
               "  -r file               Read reference symbols from a file\n"
@@ -763,7 +762,7 @@ int main(int argc, char **argv)
 
 #ifdef __GNU_LIBRARY__
         struct option long_opts[] = {
-                {"arch", 1, 0, 'a'},
+                {"symbol-prefix", 1, 0, 's'},
                 {"debug", 0, 0, 'd'},
                 {"warnings", 0, 0, 'w'},
                 {"quiet", 0, 0, 'q'},
@@ -776,14 +775,14 @@ int main(int argc, char **argv)
                 {0, 0, 0, 0}
         };
 
-        while ((o = getopt_long(argc, argv, "a:dwqVDr:T:ph",
+        while ((o = getopt_long(argc, argv, "s:dwqVDr:T:ph",
                                 &long_opts[0], NULL)) != EOF)
 #else                           /* __GNU_LIBRARY__ */
-        while ((o = getopt(argc, argv, "a:dwqVDr:T:ph")) != EOF)
+        while ((o = getopt(argc, argv, "s:dwqVDr:T:ph")) != EOF)
 #endif                          /* __GNU_LIBRARY__ */
                 switch (o) {
-                case 'a':
-                        arch = optarg;
+                case 's':
+                        mod_prefix = optarg;
                         break;
                 case 'd':
                         flag_debug++;
@@ -826,9 +825,6 @@ int main(int argc, char **argv)
                         genksyms_usage();
                         return 1;
                 }
-        if ((strcmp(arch, "h8300") == 0) || (strcmp(arch, "blackfin") == 0) ||
-            (strcmp(arch, "metag") == 0))
-                mod_prefix = "_";
         {
                 extern int yydebug;
                 extern int yy_flex_debug;
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index 3d569d6022c2..014994936b1c 100644
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -74,9 +74,8 @@ kallsyms()
         info KSYM ${2}
         local kallsymopt;
 
-        if [ -n "${CONFIG_SYMBOL_PREFIX}" ]; then
-                kallsymopt="${kallsymopt} \
-                            --symbol-prefix=${CONFIG_SYMBOL_PREFIX}"
+        if [ -n "${CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX}" ]; then
+                kallsymopt="${kallsymopt} --symbol-prefix=_"
         fi
 
         if [ -n "${CONFIG_KALLSYMS_ALL}" ]; then
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 78b30c1548e9..a4be8e112bb6 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -15,17 +15,12 @@
 #include <stdio.h>
 #include <ctype.h>
 #include <string.h>
+#include <limits.h>
+#include <stdbool.h>
 #include "modpost.h"
 #include "../../include/generated/autoconf.h"
 #include "../../include/linux/license.h"
-
-/* Some toolchains use a `_' prefix for all user symbols. */
-#ifdef CONFIG_SYMBOL_PREFIX
-#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
-#else
-#define MODULE_SYMBOL_PREFIX ""
-#endif
-
+#include "../../include/linux/export.h"
 
 /* Are we using CONFIG_MODVERSIONS? */
 int modversions = 0;
@@ -85,6 +80,14 @@ PRINTF void merror(const char *fmt, ...)
         va_end(arglist);
 }
 
+static inline bool strends(const char *str, const char *postfix)
+{
+        if (strlen(str) < strlen(postfix))
+                return false;
+
+        return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
+}
+
 static int is_vmlinux(const char *modname)
 {
         const char *myname;
@@ -120,22 +123,20 @@ static struct module *find_module(char *modname)
         return mod;
 }
 
-static struct module *new_module(char *modname)
+static struct module *new_module(const char *modname)
 {
         struct module *mod;
-        char *p, *s;
+        char *p;
 
         mod = NOFAIL(malloc(sizeof(*mod)));
         memset(mod, 0, sizeof(*mod));
         p = NOFAIL(strdup(modname));
 
         /* strip trailing .o */
-        s = strrchr(p, '.');
-        if (s != NULL)
-                if (strcmp(s, ".o") == 0) {
-                        *s = '\0';
-                        mod->is_dot_o = 1;
-                }
+        if (strends(p, ".o")) {
+                p[strlen(p) - 2] = '\0';
+                mod->is_dot_o = 1;
+        }
 
         /* add to list */
         mod->name = p;
@@ -562,7 +563,7 @@ static void parse_elf_finish(struct elf_info *info)
 static int ignore_undef_symbol(struct elf_info *info, const char *symname)
 {
         /* ignore __this_module, it will be resolved shortly */
-        if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
+        if (strcmp(symname, VMLINUX_SYMBOL_STR(__this_module)) == 0)
                 return 1;
         /* ignore global offset table */
         if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
@@ -583,8 +584,8 @@ static int ignore_undef_symbol(struct elf_info *info, const char *symname)
         return 0;
 }
 
-#define CRC_PFX     MODULE_SYMBOL_PREFIX "__crc_"
-#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
+#define CRC_PFX     VMLINUX_SYMBOL_STR(__crc_)
+#define KSYMTAB_PFX VMLINUX_SYMBOL_STR(__ksymtab_)
 
 static void handle_modversions(struct module *mod, struct elf_info *info,
                                Elf_Sym *sym, const char *symname)
@@ -637,14 +638,15 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
                 }
 #endif
 
-                if (memcmp(symname, MODULE_SYMBOL_PREFIX,
-                           strlen(MODULE_SYMBOL_PREFIX)) == 0) {
-                        mod->unres =
-                          alloc_symbol(symname +
-                                       strlen(MODULE_SYMBOL_PREFIX),
-                                       ELF_ST_BIND(sym->st_info) == STB_WEAK,
-                                       mod->unres);
-                }
+#ifdef CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX
+                if (symname[0] != '_')
+                        break;
+                else
+                        symname++;
+#endif
+                mod->unres = alloc_symbol(symname,
+                                          ELF_ST_BIND(sym->st_info) == STB_WEAK,
+                                          mod->unres);
                 break;
         default:
                 /* All exported symbols */
@@ -652,9 +654,9 @@ static void handle_modversions(struct module *mod, struct elf_info *info,
                         sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
                                         export);
                 }
-                if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
+                if (strcmp(symname, VMLINUX_SYMBOL_STR(init_module)) == 0)
                         mod->has_init = 1;
-                if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
+                if (strcmp(symname, VMLINUX_SYMBOL_STR(cleanup_module)) == 0)
                         mod->has_cleanup = 1;
                 break;
         }
@@ -1762,6 +1764,27 @@ static void read_symbols(char *modname)
                 mod->unres = alloc_symbol("module_layout", 0, mod->unres);
 }
 
+static void read_symbols_from_files(const char *filename)
+{
+        FILE *in = stdin;
+        char fname[PATH_MAX];
+
+        if (strcmp(filename, "-") != 0) {
+                in = fopen(filename, "r");
+                if (!in)
+                        fatal("Can't open filenames file %s: %m", filename);
+        }
+
+        while (fgets(fname, PATH_MAX, in) != NULL) {
+                if (strends(fname, "\n"))
+                        fname[strlen(fname)-1] = '\0';
+                read_symbols(fname);
+        }
+
+        if (in != stdin)
+                fclose(in);
+}
+
 #define SZ 500
 
 /* We first write the generated file into memory using the
@@ -1934,7 +1957,8 @@ static int add_versions(struct buffer *b, struct module *mod)
                                 s->name, mod->name);
                         continue;
                 }
-                buf_printf(b, "\t{ %#8x, \"%s\" },\n", s->crc, s->name);
+                buf_printf(b, "\t{ %#8x, __VMLINUX_SYMBOL_STR(%s) },\n",
+                           s->crc, s->name);
         }
 
         buf_printf(b, "};\n");
@@ -2122,13 +2146,13 @@ int main(int argc, char **argv)
         struct module *mod;
         struct buffer buf = { };
         char *kernel_read = NULL, *module_read = NULL;
-        char *dump_write = NULL;
+        char *dump_write = NULL, *files_source = NULL;
         int opt;
         int err;
         struct ext_sym_list *extsym_iter;
         struct ext_sym_list *extsym_start = NULL;
 
-        while ((opt = getopt(argc, argv, "i:I:e:msSo:awM:K:")) != -1) {
+        while ((opt = getopt(argc, argv, "i:I:e:msST:o:awM:K:")) != -1) {
                 switch (opt) {
                 case 'i':
                         kernel_read = optarg;
@@ -2160,6 +2184,9 @@ int main(int argc, char **argv)
                 case 'S':
                         sec_mismatch_verbose = 0;
                         break;
+                case 'T':
+                        files_source = optarg;
+                        break;
                 case 'w':
                         warn_unresolved = 1;
                         break;
@@ -2182,6 +2209,9 @@ int main(int argc, char **argv)
         while (optind < argc)
                 read_symbols(argv[optind++]);
 
+        if (files_source)
+                read_symbols_from_files(files_source);
+
         for (mod = modules; mod; mod = mod->next) {
                 if (mod->skip)
                         continue;