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| author | Alexei Starovoitov <ast@fb.com> | 2016-11-07 15:14:20 -0800 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2016-11-14 16:31:41 -0500 |
| commit | 977c1f9c8c022d0173181766b34a0db3705265a4 (patch) | |
| tree | 8b38040b883d49ced50f39d17e35f7f8d6c2a126 /kernel/trace | |
| parent | a25f0944ba9b1d8a6813fd6f1a86f1bd59ac25a6 (diff) | |
| download | linux-977c1f9c8c022d0173181766b34a0db3705265a4.tar.gz | |
ftrace: Ignore FTRACE_FL_DISABLED while walking dyn_ftrace records
ftrace_shutdown() checks for sanity of ftrace records and if dyn_ftrace->flags is not zero, it will warn. It can happen that 'flags' are set to FTRACE_FL_DISABLED at this point, since some module was loaded, but before ftrace_module_enable() cleared the flags for this module. In other words the module.c is doing: ftrace_module_init(mod); // calls ftrace_update_code() that sets flags=FTRACE_FL_DISABLED ... // here ftrace_shutdown() is called that warns, since err = prepare_coming_module(mod); // didn't have a chance to clear FTRACE_FL_DISABLED Fix it by ignoring disabled records. It's similar to what __ftrace_hash_rec_update() is already doing. Link: http://lkml.kernel.org/r/1478560460-3818619-1-git-send-email-ast@fb.com Cc: stable@vger.kernel.org Fixes: b7ffffbb46f2 "ftrace: Add infrastructure for delayed enabling of module functions" Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/ftrace.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 2050a7652a86..326498baab83 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2763,7 +2763,7 @@ static int ftrace_shutdown(struct ftrace_ops *ops, int command) struct dyn_ftrace *rec; do_for_each_ftrace_rec(pg, rec) { - if (FTRACE_WARN_ON_ONCE(rec->flags)) + if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED)) pr_warn(" %pS flags:%lx\n", (void *)rec->ip, rec->flags); } while_for_each_ftrace_rec(); |