summaryrefslogtreecommitdiff
path: root/kernel/module.c
diff options
context:
space:
mode:
authorTakashi Iwai <tiwai@suse.de>2016-03-07 11:06:46 +0100
committerTakashi Iwai <tiwai@suse.de>2016-03-07 11:06:46 +0100
commitad09ef2cce91e3a98a32e3bb0a5982a6e8920aa1 (patch)
tree6d46455cb546b65b041acc1293043c71ef93da40 /kernel/module.c
parent790b415c98de62602810b0eedce26f0f9d6ddd78 (diff)
parent02db17ff376893f65f45974b0897e70e6695034e (diff)
Merge tag 'asoc-fix-v4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v4.5 This is far too big a set of fixes for this late in the release cycle but the overwhelming bulk is essentially the same simple fix from Takashi for a cut'n'pasted 64 bit cleanliness issue in the userspace interface where drivers were accessing things using the wrong element in a union which worked OK on 32 bit platforms as the correct element happened to be aligned the same way but with 64 bit platforms ABIs are different and the two members of the union are laid out in different places. They aren't all tagged to stable since some of these chips have vanishingly little chance of being used in 64 bit systems. The other changes are: - A fix for Qualcomm devices to work on big endian systems. The original change is actually correct but triggered a bug in regmap which is too invasive to fix for this cycle and can be worked around by just letting regmap pick the default. - A fix for the Samsung I2S driver locking which wasn't using IRQ safe spinlocks when it needed to. - A fix for the new Intel Sky Lake driver forgetting that C pointer arithmetic takes the type of the pointer into consideration. - A revert of a change to the FSL SSI driver that broke some systems. - A fix for the cleanup path of the wm9713 driver. - A fix for some incorrect register definitions in the ADAU17x1 driver that caused misclocking in some configurations. - A fix for the tracepoints for jack detection to avoid using an internal field of the core jack structure which is no longer present in all configurations. - A fix for another of the new Intel drivers which tried to write to a string literal.
Diffstat (limited to 'kernel/module.c')
-rw-r--r--kernel/module.c124
1 files changed, 79 insertions, 45 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 8358f4697c0c..794ebe8e878d 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -303,6 +303,9 @@ struct load_info {
struct _ddebug *debug;
unsigned int num_debug;
bool sig_ok;
+#ifdef CONFIG_KALLSYMS
+ unsigned long mod_kallsyms_init_off;
+#endif
struct {
unsigned int sym, str, mod, vers, info, pcpu;
} index;
@@ -981,6 +984,8 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
mod->exit();
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
+ ftrace_release_mod(mod);
+
async_synchronize_full();
/* Store the name of the last unloaded module for diagnostic purposes */
@@ -2480,10 +2485,21 @@ static void layout_symtab(struct module *mod, struct load_info *info)
strsect->sh_flags |= SHF_ALLOC;
strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
info->index.str) | INIT_OFFSET_MASK;
- mod->init_layout.size = debug_align(mod->init_layout.size);
pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
+
+ /* We'll tack temporary mod_kallsyms on the end. */
+ mod->init_layout.size = ALIGN(mod->init_layout.size,
+ __alignof__(struct mod_kallsyms));
+ info->mod_kallsyms_init_off = mod->init_layout.size;
+ mod->init_layout.size += sizeof(struct mod_kallsyms);
+ mod->init_layout.size = debug_align(mod->init_layout.size);
}
+/*
+ * We use the full symtab and strtab which layout_symtab arranged to
+ * be appended to the init section. Later we switch to the cut-down
+ * core-only ones.
+ */
static void add_kallsyms(struct module *mod, const struct load_info *info)
{
unsigned int i, ndst;
@@ -2492,29 +2508,34 @@ static void add_kallsyms(struct module *mod, const struct load_info *info)
char *s;
Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
- mod->symtab = (void *)symsec->sh_addr;
- mod->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
+ /* Set up to point into init section. */
+ mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
+
+ mod->kallsyms->symtab = (void *)symsec->sh_addr;
+ mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
/* Make sure we get permanent strtab: don't use info->strtab. */
- mod->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
+ mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
/* Set types up while we still have access to sections. */
- for (i = 0; i < mod->num_symtab; i++)
- mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
-
- mod->core_symtab = dst = mod->core_layout.base + info->symoffs;
- mod->core_strtab = s = mod->core_layout.base + info->stroffs;
- src = mod->symtab;
- for (ndst = i = 0; i < mod->num_symtab; i++) {
+ for (i = 0; i < mod->kallsyms->num_symtab; i++)
+ mod->kallsyms->symtab[i].st_info
+ = elf_type(&mod->kallsyms->symtab[i], info);
+
+ /* Now populate the cut down core kallsyms for after init. */
+ mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
+ mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
+ src = mod->kallsyms->symtab;
+ for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
if (i == 0 ||
is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
info->index.pcpu)) {
dst[ndst] = src[i];
- dst[ndst++].st_name = s - mod->core_strtab;
- s += strlcpy(s, &mod->strtab[src[i].st_name],
+ dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
+ s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
KSYM_NAME_LEN) + 1;
}
}
- mod->core_num_syms = ndst;
+ mod->core_kallsyms.num_symtab = ndst;
}
#else
static inline void layout_symtab(struct module *mod, struct load_info *info)
@@ -3263,9 +3284,8 @@ static noinline int do_init_module(struct module *mod)
module_put(mod);
trim_init_extable(mod);
#ifdef CONFIG_KALLSYMS
- mod->num_symtab = mod->core_num_syms;
- mod->symtab = mod->core_symtab;
- mod->strtab = mod->core_strtab;
+ /* Switch to core kallsyms now init is done: kallsyms may be walking! */
+ rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
#endif
mod_tree_remove_init(mod);
disable_ro_nx(&mod->init_layout);
@@ -3295,6 +3315,7 @@ fail:
module_put(mod);
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
+ ftrace_release_mod(mod);
free_module(mod);
wake_up_all(&module_wq);
return ret;
@@ -3371,6 +3392,7 @@ static int complete_formation(struct module *mod, struct load_info *info)
mod->state = MODULE_STATE_COMING;
mutex_unlock(&module_mutex);
+ ftrace_module_enable(mod);
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_COMING, mod);
return 0;
@@ -3496,7 +3518,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
/* Module is ready to execute: parsing args may do that. */
after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
- -32768, 32767, NULL,
+ -32768, 32767, mod,
unknown_module_param_cb);
if (IS_ERR(after_dashes)) {
err = PTR_ERR(after_dashes);
@@ -3627,6 +3649,11 @@ static inline int is_arm_mapping_symbol(const char *str)
&& (str[2] == '\0' || str[2] == '.');
}
+static const char *symname(struct mod_kallsyms *kallsyms, unsigned int symnum)
+{
+ return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
+}
+
static const char *get_ksymbol(struct module *mod,
unsigned long addr,
unsigned long *size,
@@ -3634,6 +3661,7 @@ static const char *get_ksymbol(struct module *mod,
{
unsigned int i, best = 0;
unsigned long nextval;
+ struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
/* At worse, next value is at end of module */
if (within_module_init(addr, mod))
@@ -3643,32 +3671,32 @@ static const char *get_ksymbol(struct module *mod,
/* Scan for closest preceding symbol, and next symbol. (ELF
starts real symbols at 1). */
- for (i = 1; i < mod->num_symtab; i++) {
- if (mod->symtab[i].st_shndx == SHN_UNDEF)
+ for (i = 1; i < kallsyms->num_symtab; i++) {
+ if (kallsyms->symtab[i].st_shndx == SHN_UNDEF)
continue;
/* We ignore unnamed symbols: they're uninformative
* and inserted at a whim. */
- if (mod->symtab[i].st_value <= addr
- && mod->symtab[i].st_value > mod->symtab[best].st_value
- && *(mod->strtab + mod->symtab[i].st_name) != '\0'
- && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
+ if (*symname(kallsyms, i) == '\0'
+ || is_arm_mapping_symbol(symname(kallsyms, i)))
+ continue;
+
+ if (kallsyms->symtab[i].st_value <= addr
+ && kallsyms->symtab[i].st_value > kallsyms->symtab[best].st_value)
best = i;
- if (mod->symtab[i].st_value > addr
- && mod->symtab[i].st_value < nextval
- && *(mod->strtab + mod->symtab[i].st_name) != '\0'
- && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
- nextval = mod->symtab[i].st_value;
+ if (kallsyms->symtab[i].st_value > addr
+ && kallsyms->symtab[i].st_value < nextval)
+ nextval = kallsyms->symtab[i].st_value;
}
if (!best)
return NULL;
if (size)
- *size = nextval - mod->symtab[best].st_value;
+ *size = nextval - kallsyms->symtab[best].st_value;
if (offset)
- *offset = addr - mod->symtab[best].st_value;
- return mod->strtab + mod->symtab[best].st_name;
+ *offset = addr - kallsyms->symtab[best].st_value;
+ return symname(kallsyms, best);
}
/* For kallsyms to ask for address resolution. NULL means not found. Careful
@@ -3758,19 +3786,21 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
preempt_disable();
list_for_each_entry_rcu(mod, &modules, list) {
+ struct mod_kallsyms *kallsyms;
+
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- if (symnum < mod->num_symtab) {
- *value = mod->symtab[symnum].st_value;
- *type = mod->symtab[symnum].st_info;
- strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
- KSYM_NAME_LEN);
+ kallsyms = rcu_dereference_sched(mod->kallsyms);
+ if (symnum < kallsyms->num_symtab) {
+ *value = kallsyms->symtab[symnum].st_value;
+ *type = kallsyms->symtab[symnum].st_info;
+ strlcpy(name, symname(kallsyms, symnum), KSYM_NAME_LEN);
strlcpy(module_name, mod->name, MODULE_NAME_LEN);
*exported = is_exported(name, *value, mod);
preempt_enable();
return 0;
}
- symnum -= mod->num_symtab;
+ symnum -= kallsyms->num_symtab;
}
preempt_enable();
return -ERANGE;
@@ -3779,11 +3809,12 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
static unsigned long mod_find_symname(struct module *mod, const char *name)
{
unsigned int i;
+ struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
- for (i = 0; i < mod->num_symtab; i++)
- if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
- mod->symtab[i].st_info != 'U')
- return mod->symtab[i].st_value;
+ for (i = 0; i < kallsyms->num_symtab; i++)
+ if (strcmp(name, symname(kallsyms, i)) == 0 &&
+ kallsyms->symtab[i].st_info != 'U')
+ return kallsyms->symtab[i].st_value;
return 0;
}
@@ -3822,11 +3853,14 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
module_assert_mutex();
list_for_each_entry(mod, &modules, list) {
+ /* We hold module_mutex: no need for rcu_dereference_sched */
+ struct mod_kallsyms *kallsyms = mod->kallsyms;
+
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- for (i = 0; i < mod->num_symtab; i++) {
- ret = fn(data, mod->strtab + mod->symtab[i].st_name,
- mod, mod->symtab[i].st_value);
+ for (i = 0; i < kallsyms->num_symtab; i++) {
+ ret = fn(data, symname(kallsyms, i),
+ mod, kallsyms->symtab[i].st_value);
if (ret != 0)
return ret;
}