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Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r--kernel/trace/ftrace.c57
1 files changed, 52 insertions, 5 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fc88e0688daf..92015de6203d 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1293,6 +1293,8 @@ static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
void ftrace_free_filter(struct ftrace_ops *ops)
{
ftrace_ops_init(ops);
+ if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
+ return;
free_ftrace_hash(ops->func_hash->filter_hash);
free_ftrace_hash(ops->func_hash->notrace_hash);
}
@@ -7016,6 +7018,7 @@ static int ftrace_process_locs(struct module *mod,
unsigned long *p;
unsigned long addr;
unsigned long flags = 0; /* Shut up gcc */
+ unsigned long pages;
int ret = -ENOMEM;
count = end - start;
@@ -7023,6 +7026,8 @@ static int ftrace_process_locs(struct module *mod,
if (!count)
return 0;
+ pages = DIV_ROUND_UP(count, ENTRIES_PER_PAGE);
+
/*
* Sorting mcount in vmlinux at build time depend on
* CONFIG_BUILDTIME_MCOUNT_SORT, while mcount loc in
@@ -7067,7 +7072,9 @@ static int ftrace_process_locs(struct module *mod,
pg = start_pg;
while (p < end) {
unsigned long end_offset;
- addr = ftrace_call_adjust(*p++);
+
+ addr = *p++;
+
/*
* Some architecture linkers will pad between
* the different mcount_loc sections of different
@@ -7079,6 +7086,19 @@ static int ftrace_process_locs(struct module *mod,
continue;
}
+ /*
+ * If this is core kernel, make sure the address is in core
+ * or inittext, as weak functions get zeroed and KASLR can
+ * move them to something other than zero. It just will not
+ * move it to an area where kernel text is.
+ */
+ if (!mod && !(is_kernel_text(addr) || is_kernel_inittext(addr))) {
+ skipped++;
+ continue;
+ }
+
+ addr = ftrace_call_adjust(addr);
+
end_offset = (pg->index+1) * sizeof(pg->records[0]);
if (end_offset > PAGE_SIZE << pg->order) {
/* We should have allocated enough */
@@ -7118,11 +7138,41 @@ static int ftrace_process_locs(struct module *mod,
/* We should have used all pages unless we skipped some */
if (pg_unuse) {
- WARN_ON(!skipped);
+ unsigned long pg_remaining, remaining = 0;
+ unsigned long skip;
+
+ /* Count the number of entries unused and compare it to skipped. */
+ pg_remaining = (ENTRIES_PER_PAGE << pg->order) - pg->index;
+
+ if (!WARN(skipped < pg_remaining, "Extra allocated pages for ftrace")) {
+
+ skip = skipped - pg_remaining;
+
+ for (pg = pg_unuse; pg; pg = pg->next)
+ remaining += 1 << pg->order;
+
+ pages -= remaining;
+
+ skip = DIV_ROUND_UP(skip, ENTRIES_PER_PAGE);
+
+ /*
+ * Check to see if the number of pages remaining would
+ * just fit the number of entries skipped.
+ */
+ WARN(skip != remaining, "Extra allocated pages for ftrace: %lu with %lu skipped",
+ remaining, skipped);
+ }
/* Need to synchronize with ftrace_location_range() */
synchronize_rcu();
ftrace_free_pages(pg_unuse);
}
+
+ if (!mod) {
+ count -= skipped;
+ pr_info("ftrace: allocating %ld entries in %ld pages\n",
+ count, pages);
+ }
+
return ret;
}
@@ -7768,9 +7818,6 @@ void __init ftrace_init(void)
goto failed;
}
- pr_info("ftrace: allocating %ld entries in %ld pages\n",
- count, DIV_ROUND_UP(count, ENTRIES_PER_PAGE));
-
ret = ftrace_process_locs(NULL,
__start_mcount_loc,
__stop_mcount_loc);