diff options
| author |   David S. Miller <davem@davemloft.net> | 2019-09-02 11:20:17 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-09-02 11:20:17 -0700 |
| commit | 765b7590c92d849806e9a27ab3a5a17cfc6a47a9 (patch) | |
| tree | 4387f5034f870accfd2bb56997c535159da45f06 /kernel/trace/ftrace.c | |
| parent | Merge branch 'net-dsa-mv88e6xxx-centralize-SERDES-IRQ-handling' (diff) | |
| parent | Linux 5.3-rc7 (diff) | |
| download | wireguard-linux-765b7590c92d849806e9a27ab3a5a17cfc6a47a9.tar.xz wireguard-linux-765b7590c92d849806e9a27ab3a5a17cfc6a47a9.zip | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
r8152 conflicts are the NAPI fixes in 'net' overlapping with
some tasklet stuff in net-next
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'kernel/trace/ftrace.c')
| -rw-r--r-- | kernel/trace/ftrace.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index eca34503f178..f9821a3374e9 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3095,6 +3095,14 @@ t_probe_next(struct seq_file *m, loff_t *pos) hnd = &iter->probe_entry->hlist; hash = iter->probe->ops.func_hash->filter_hash; + + /* + * A probe being registered may temporarily have an empty hash + * and it's at the end of the func_probes list. + */ + if (!hash || hash == EMPTY_HASH) + return NULL; + size = 1 << hash->size_bits; retry: @@ -4320,12 +4328,21 @@ register_ftrace_function_probe(char *glob, struct trace_array *tr, mutex_unlock(&ftrace_lock); + /* + * Note, there's a small window here that the func_hash->filter_hash + * may be NULL or empty. Need to be carefule when reading the loop. + */ mutex_lock(&probe->ops.func_hash->regex_lock); orig_hash = &probe->ops.func_hash->filter_hash; old_hash = *orig_hash; hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash); + if (!hash) { + ret = -ENOMEM; + goto out; + } + ret = ftrace_match_records(hash, glob, strlen(glob)); /* Nothing found? */ |