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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-06-10 05:30:17 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-06-10 05:30:17 -0300
commitd635711daa98be86d4c7fd01499c34f566b54ccb (patch)
treeaa5cc3760a27c3d57146498cb82fa549547de06c /kernel/kallsyms.c
parentc91265cd0efb83778f015b4d4b1129bd2cfd075e (diff)
Linux-libre 4.6.2-gnu
Diffstat (limited to 'kernel/kallsyms.c')
-rw-r--r--kernel/kallsyms.c42
1 files changed, 33 insertions, 9 deletions
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 5c5987f10..fafd1a3ef 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -38,6 +38,7 @@
* during the second link stage.
*/
extern const unsigned long kallsyms_addresses[] __weak;
+extern const int kallsyms_offsets[] __weak;
extern const u8 kallsyms_names[] __weak;
/*
@@ -47,6 +48,9 @@ extern const u8 kallsyms_names[] __weak;
extern const unsigned long kallsyms_num_syms
__attribute__((weak, section(".rodata")));
+extern const unsigned long kallsyms_relative_base
+__attribute__((weak, section(".rodata")));
+
extern const u8 kallsyms_token_table[] __weak;
extern const u16 kallsyms_token_index[] __weak;
@@ -176,6 +180,23 @@ static unsigned int get_symbol_offset(unsigned long pos)
return name - kallsyms_names;
}
+static unsigned long kallsyms_sym_address(int idx)
+{
+ if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE))
+ return kallsyms_addresses[idx];
+
+ /* values are unsigned offsets if --absolute-percpu is not in effect */
+ if (!IS_ENABLED(CONFIG_KALLSYMS_ABSOLUTE_PERCPU))
+ return kallsyms_relative_base + (u32)kallsyms_offsets[idx];
+
+ /* ...otherwise, positive offsets are absolute values */
+ if (kallsyms_offsets[idx] >= 0)
+ return kallsyms_offsets[idx];
+
+ /* ...and negative offsets are relative to kallsyms_relative_base - 1 */
+ return kallsyms_relative_base - 1 - kallsyms_offsets[idx];
+}
+
/* Lookup the address for this symbol. Returns 0 if not found. */
unsigned long kallsyms_lookup_name(const char *name)
{
@@ -187,7 +208,7 @@ unsigned long kallsyms_lookup_name(const char *name)
off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf));
if (strcmp(namebuf, name) == 0)
- return kallsyms_addresses[i];
+ return kallsyms_sym_address(i);
}
return module_kallsyms_lookup_name(name);
}
@@ -204,7 +225,7 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
off = kallsyms_expand_symbol(off, namebuf, ARRAY_SIZE(namebuf));
- ret = fn(data, namebuf, NULL, kallsyms_addresses[i]);
+ ret = fn(data, namebuf, NULL, kallsyms_sym_address(i));
if (ret != 0)
return ret;
}
@@ -220,7 +241,10 @@ static unsigned long get_symbol_pos(unsigned long addr,
unsigned long i, low, high, mid;
/* This kernel should never had been booted. */
- BUG_ON(!kallsyms_addresses);
+ if (!IS_ENABLED(CONFIG_KALLSYMS_BASE_RELATIVE))
+ BUG_ON(!kallsyms_addresses);
+ else
+ BUG_ON(!kallsyms_offsets);
/* Do a binary search on the sorted kallsyms_addresses array. */
low = 0;
@@ -228,7 +252,7 @@ static unsigned long get_symbol_pos(unsigned long addr,
while (high - low > 1) {
mid = low + (high - low) / 2;
- if (kallsyms_addresses[mid] <= addr)
+ if (kallsyms_sym_address(mid) <= addr)
low = mid;
else
high = mid;
@@ -238,15 +262,15 @@ static unsigned long get_symbol_pos(unsigned long addr,
* Search for the first aliased symbol. Aliased
* symbols are symbols with the same address.
*/
- while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low])
+ while (low && kallsyms_sym_address(low-1) == kallsyms_sym_address(low))
--low;
- symbol_start = kallsyms_addresses[low];
+ symbol_start = kallsyms_sym_address(low);
/* Search for next non-aliased symbol. */
for (i = low + 1; i < kallsyms_num_syms; i++) {
- if (kallsyms_addresses[i] > symbol_start) {
- symbol_end = kallsyms_addresses[i];
+ if (kallsyms_sym_address(i) > symbol_start) {
+ symbol_end = kallsyms_sym_address(i);
break;
}
}
@@ -470,7 +494,7 @@ static unsigned long get_ksymbol_core(struct kallsym_iter *iter)
unsigned off = iter->nameoff;
iter->module_name[0] = '\0';
- iter->value = kallsyms_addresses[iter->pos];
+ iter->value = kallsyms_sym_address(iter->pos);
iter->type = kallsyms_get_symbol_type(off);