diff options
| author | Chengming Zhou <zhouchengming@bytedance.com> | 2020-07-29 02:05:53 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-01 11:11:49 +0200 |
| commit | 2d81575a4bda48981dec3d51509569fc9ae67044 (patch) | |
| tree | 1b11238fb4e4a3d79d585d32912e61d2ac74bda3 /kernel/trace/ftrace.c | |
| parent | 7801c0bb58523af7b3aaddf8983a6a695242d6c3 (diff) | |
ftrace: Setup correct FTRACE_FL_REGS flags for module
[ Upstream commit 8a224ffb3f52b0027f6b7279854c71a31c48fc97 ]
When module loaded and enabled, we will use __ftrace_replace_code
for module if any ftrace_ops referenced it found. But we will get
wrong ftrace_addr for module rec in ftrace_get_addr_new, because
rec->flags has not been setup correctly. It can cause the callback
function of a ftrace_ops has FTRACE_OPS_FL_SAVE_REGS to be called
with pt_regs set to NULL.
So setup correct FTRACE_FL_REGS flags for rec when we call
referenced_filters to find ftrace_ops references it.
Link: https://lkml.kernel.org/r/20200728180554.65203-1-zhouchengming@bytedance.com
Cc: stable@vger.kernel.org
Fixes: 8c4f3c3fa9681 ("ftrace: Check module functions being traced on reload")
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/trace/ftrace.c')
| -rw-r--r-- | kernel/trace/ftrace.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index e4c6f89b6b11..89ed01911a9a 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2823,8 +2823,11 @@ static int referenced_filters(struct dyn_ftrace *rec) int cnt = 0; for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) { - if (ops_references_rec(ops, rec)) - cnt++; + if (ops_references_rec(ops, rec)) { + cnt++; + if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) + rec->flags |= FTRACE_FL_REGS; + } } return cnt; @@ -2874,7 +2877,7 @@ static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs) p = &pg->records[i]; if (test) cnt += referenced_filters(p); - p->flags = cnt; + p->flags += cnt; /* * Do the initial record conversion from mcount jump |