From: Menglong Dong <menglong8.dong@gmail.com>
The maximum of the ftrace hash bits is made fls(32) in
register_ftrace_direct(), which seems illogical. So, we fix it by making
the max hash bits FTRACE_HASH_MAX_BITS instead.
Link: https://lore.kernel.org/20250413014444.36724-1-dongml2@chinatelecom.cn
Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use")
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
kernel/trace/ftrace.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 41dcfcf8b40a..61130bb34d6c 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5964,9 +5964,10 @@ int register_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
/* Make a copy hash to place the new and the old entries in */
size = hash->count + direct_functions->count;
- if (size > 32)
- size = 32;
- new_hash = alloc_ftrace_hash(fls(size));
+ size = fls(size);
+ if (size > FTRACE_HASH_MAX_BITS)
+ size = FTRACE_HASH_MAX_BITS;
+ new_hash = alloc_ftrace_hash(size);
if (!new_hash)
goto out_unlock;
--
2.47.2