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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Mainly boring here, too.  rmmod --wait finally removed, though"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: fix bogus 'exported twice' warnings.
  init: fix in-place parameter modification regression
  asmlinkage, module: Make ksymtab and kcrctab symbols and __this_module __visible
  kernel: add support for init_array constructors
  modpost: Optionally ignore secondary errors seen if a single module build fails
  module: remove rmmod --wait option.
Linus Torvalds 11 years ago
parent
commit
ce6513f758

+ 1 - 0
include/asm-generic/vmlinux.lds.h

@@ -473,6 +473,7 @@
 #define KERNEL_CTORS()	. = ALIGN(8);			   \
 			VMLINUX_SYMBOL(__ctors_start) = .; \
 			*(.ctors)			   \
+			*(.init_array)			   \
 			VMLINUX_SYMBOL(__ctors_end) = .;
 #else
 #define KERNEL_CTORS()

+ 2 - 2
include/linux/export.h

@@ -43,7 +43,7 @@ extern struct module __this_module;
 /* Mark the CRC weak since genksyms apparently decides not to
  * generate a checksums for some symbols */
 #define __CRC_SYMBOL(sym, sec)					\
-	extern void *__crc_##sym __attribute__((weak));		\
+	extern __visible void *__crc_##sym __attribute__((weak));		\
 	static const unsigned long __kcrctab_##sym		\
 	__used							\
 	__attribute__((section("___kcrctab" sec "+" #sym), unused))	\
@@ -59,7 +59,7 @@ extern struct module __this_module;
 	static const char __kstrtab_##sym[]			\
 	__attribute__((section("__ksymtab_strings"), aligned(1))) \
 	= VMLINUX_SYMBOL_STR(sym);				\
-	static const struct kernel_symbol __ksymtab_##sym	\
+	__visible const struct kernel_symbol __ksymtab_##sym	\
 	__used							\
 	__attribute__((section("___ksymtab" sec "+" #sym), unused))	\
 	= { (unsigned long)&sym, __kstrtab_##sym }

+ 0 - 3
include/linux/module.h

@@ -367,9 +367,6 @@ struct module
 	/* What modules do I depend on? */
 	struct list_head target_list;
 
-	/* Who is waiting for us to be unloaded */
-	struct task_struct *waiter;
-
 	/* Destruction function. */
 	void (*exit)(void);
 

+ 5 - 2
init/main.c

@@ -131,6 +131,8 @@ char __initdata boot_command_line[COMMAND_LINE_SIZE];
 char *saved_command_line;
 /* Command line for parameter parsing */
 static char *static_command_line;
+/* Command line for per-initcall parameter parsing */
+static char *initcall_command_line;
 
 static char *execute_command;
 static char *ramdisk_execute_command;
@@ -354,6 +356,7 @@ static inline void smp_prepare_cpus(unsigned int maxcpus) { }
 static void __init setup_command_line(char *command_line)
 {
 	saved_command_line = alloc_bootmem(strlen (boot_command_line)+1);
+	initcall_command_line = alloc_bootmem(strlen (boot_command_line)+1);
 	static_command_line = alloc_bootmem(strlen (command_line)+1);
 	strcpy (saved_command_line, boot_command_line);
 	strcpy (static_command_line, command_line);
@@ -751,9 +754,9 @@ static void __init do_initcall_level(int level)
 	extern const struct kernel_param __start___param[], __stop___param[];
 	initcall_t *fn;
 
-	strcpy(static_command_line, saved_command_line);
+	strcpy(initcall_command_line, saved_command_line);
 	parse_args(initcall_level_names[level],
-		   static_command_line, __start___param,
+		   initcall_command_line, __start___param,
 		   __stop___param - __start___param,
 		   level, level,
 		   &repair_env_string);

+ 26 - 40
kernel/module.c

@@ -641,8 +641,6 @@ static int module_unload_init(struct module *mod)
 
 	/* Hold reference count during initialization. */
 	__this_cpu_write(mod->refptr->incs, 1);
-	/* Backwards compatibility macros put refcount during init. */
-	mod->waiter = current;
 
 	return 0;
 }
@@ -768,16 +766,9 @@ static int __try_stop_module(void *_sref)
 
 static int try_stop_module(struct module *mod, int flags, int *forced)
 {
-	if (flags & O_NONBLOCK) {
-		struct stopref sref = { mod, flags, forced };
+	struct stopref sref = { mod, flags, forced };
 
-		return stop_machine(__try_stop_module, &sref, NULL);
-	} else {
-		/* We don't need to stop the machine for this. */
-		mod->state = MODULE_STATE_GOING;
-		synchronize_sched();
-		return 0;
-	}
+	return stop_machine(__try_stop_module, &sref, NULL);
 }
 
 unsigned long module_refcount(struct module *mod)
@@ -810,21 +801,6 @@ EXPORT_SYMBOL(module_refcount);
 /* This exists whether we can unload or not */
 static void free_module(struct module *mod);
 
-static void wait_for_zero_refcount(struct module *mod)
-{
-	/* Since we might sleep for some time, release the mutex first */
-	mutex_unlock(&module_mutex);
-	for (;;) {
-		pr_debug("Looking at refcount...\n");
-		set_current_state(TASK_UNINTERRUPTIBLE);
-		if (module_refcount(mod) == 0)
-			break;
-		schedule();
-	}
-	current->state = TASK_RUNNING;
-	mutex_lock(&module_mutex);
-}
-
 SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 		unsigned int, flags)
 {
@@ -839,6 +815,11 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 		return -EFAULT;
 	name[MODULE_NAME_LEN-1] = '\0';
 
+	if (!(flags & O_NONBLOCK)) {
+		printk(KERN_WARNING
+		       "waiting module removal not supported: please upgrade");
+	}
+
 	if (mutex_lock_interruptible(&module_mutex) != 0)
 		return -EINTR;
 
@@ -856,8 +837,7 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 
 	/* Doing init or already dying? */
 	if (mod->state != MODULE_STATE_LIVE) {
-		/* FIXME: if (force), slam module count and wake up
-                   waiter --RR */
+		/* FIXME: if (force), slam module count damn the torpedoes */
 		pr_debug("%s already dying\n", mod->name);
 		ret = -EBUSY;
 		goto out;
@@ -873,18 +853,11 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 		}
 	}
 
-	/* Set this up before setting mod->state */
-	mod->waiter = current;
-
 	/* Stop the machine so refcounts can't move and disable module. */
 	ret = try_stop_module(mod, flags, &forced);
 	if (ret != 0)
 		goto out;
 
-	/* Never wait if forced. */
-	if (!forced && module_refcount(mod) != 0)
-		wait_for_zero_refcount(mod);
-
 	mutex_unlock(&module_mutex);
 	/* Final destruction now no one is using it. */
 	if (mod->exit != NULL)
@@ -1002,9 +975,6 @@ void module_put(struct module *module)
 		__this_cpu_inc(module->refptr->decs);
 
 		trace_module_put(module, _RET_IP_);
-		/* Maybe they're waiting for us to drop reference? */
-		if (unlikely(!module_is_live(module)))
-			wake_up_process(module->waiter);
 		preempt_enable();
 	}
 }
@@ -2728,7 +2698,7 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags)
 	return 0;
 }
 
-static void find_module_sections(struct module *mod, struct load_info *info)
+static int find_module_sections(struct module *mod, struct load_info *info)
 {
 	mod->kp = section_objs(info, "__param",
 			       sizeof(*mod->kp), &mod->num_kp);
@@ -2758,6 +2728,18 @@ static void find_module_sections(struct module *mod, struct load_info *info)
 #ifdef CONFIG_CONSTRUCTORS
 	mod->ctors = section_objs(info, ".ctors",
 				  sizeof(*mod->ctors), &mod->num_ctors);
+	if (!mod->ctors)
+		mod->ctors = section_objs(info, ".init_array",
+				sizeof(*mod->ctors), &mod->num_ctors);
+	else if (find_sec(info, ".init_array")) {
+		/*
+		 * This shouldn't happen with same compiler and binutils
+		 * building all parts of the module.
+		 */
+		printk(KERN_WARNING "%s: has both .ctors and .init_array.\n",
+		       mod->name);
+		return -EINVAL;
+	}
 #endif
 
 #ifdef CONFIG_TRACEPOINTS
@@ -2795,6 +2777,8 @@ static void find_module_sections(struct module *mod, struct load_info *info)
 
 	info->debug = section_objs(info, "__verbose",
 				   sizeof(*info->debug), &info->num_debug);
+
+	return 0;
 }
 
 static int move_module(struct module *mod, struct load_info *info)
@@ -3248,7 +3232,9 @@ static int load_module(struct load_info *info, const char __user *uargs,
 
 	/* Now we've got everything in the final locations, we can
 	 * find optional sections. */
-	find_module_sections(mod, info);
+	err = find_module_sections(mod, info);
+	if (err)
+		goto free_unload;
 
 	err = check_module_license_and_versions(mod);
 	if (err)

+ 3 - 1
scripts/Makefile.modpost

@@ -79,9 +79,11 @@ modpost = scripts/mod/modpost                    \
  $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S)      \
  $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w)
 
+MODPOST_OPT=$(subst -i,-n,$(filter -i,$(MAKEFLAGS)))
+
 # We can go over command line length here, so be careful.
 quiet_cmd_modpost = MODPOST $(words $(filter-out vmlinux FORCE, $^)) modules
-      cmd_modpost = $(MODLISTCMD) | sed 's/\.ko$$/.o/' | $(modpost) -s -T -
+      cmd_modpost = $(MODLISTCMD) | sed 's/\.ko$$/.o/' | $(modpost) $(MODPOST_OPT) -s -T -
 
 PHONY += __modpost
 __modpost: $(modules:.ko=.o) FORCE

+ 18 - 4
scripts/mod/modpost.c

@@ -17,6 +17,7 @@
 #include <string.h>
 #include <limits.h>
 #include <stdbool.h>
+#include <errno.h>
 #include "modpost.h"
 #include "../../include/generated/autoconf.h"
 #include "../../include/linux/license.h"
@@ -37,6 +38,8 @@ static int warn_unresolved = 0;
 /* How a symbol is exported */
 static int sec_mismatch_count = 0;
 static int sec_mismatch_verbose = 1;
+/* ignore missing files */
+static int ignore_missing_files;
 
 enum export {
 	export_plain,      export_unused,     export_gpl,
@@ -161,7 +164,7 @@ struct symbol {
 	unsigned int vmlinux:1;    /* 1 if symbol is defined in vmlinux */
 	unsigned int kernel:1;     /* 1 if symbol is from kernel
 				    *  (only for external modules) **/
-	unsigned int preloaded:1;  /* 1 if symbol from Module.symvers */
+	unsigned int preloaded:1;  /* 1 if symbol from Module.symvers, or crc */
 	enum export  export;       /* Type of export */
 	char name[0];
 };
@@ -329,8 +332,11 @@ static void sym_update_crc(const char *name, struct module *mod,
 {
 	struct symbol *s = find_symbol(name);
 
-	if (!s)
+	if (!s) {
 		s = new_symbol(name, mod, export);
+		/* Don't complain when we find it later. */
+		s->preloaded = 1;
+	}
 	s->crc = crc;
 	s->crc_valid = 1;
 }
@@ -407,6 +413,11 @@ static int parse_elf(struct elf_info *info, const char *filename)
 
 	hdr = grab_file(filename, &info->size);
 	if (!hdr) {
+		if (ignore_missing_files) {
+			fprintf(stderr, "%s: %s (ignored)\n", filename,
+				strerror(errno));
+			return 0;
+		}
 		perror(filename);
 		exit(1);
 	}
@@ -1852,7 +1863,7 @@ static void add_header(struct buffer *b, struct module *mod)
 	buf_printf(b, "\n");
 	buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
 	buf_printf(b, "\n");
-	buf_printf(b, "struct module __this_module\n");
+	buf_printf(b, "__visible struct module __this_module\n");
 	buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = {\n");
 	buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
 	if (mod->has_init)
@@ -2118,7 +2129,7 @@ int main(int argc, char **argv)
 	struct ext_sym_list *extsym_iter;
 	struct ext_sym_list *extsym_start = NULL;
 
-	while ((opt = getopt(argc, argv, "i:I:e:msST:o:awM:K:")) != -1) {
+	while ((opt = getopt(argc, argv, "i:I:e:mnsST:o:awM:K:")) != -1) {
 		switch (opt) {
 		case 'i':
 			kernel_read = optarg;
@@ -2138,6 +2149,9 @@ int main(int argc, char **argv)
 		case 'm':
 			modversions = 1;
 			break;
+		case 'n':
+			ignore_missing_files = 1;
+			break;
 		case 'o':
 			dump_write = optarg;
 			break;