ftrace: fix incorrect hash size in register_ftrace_direct()

[ Upstream commit 92f1d3b40179b15630d72e2c6e4e25a899b67ba9 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Menglong Dong
2025-04-13 09:44:44 +08:00
committed by Greg Kroah-Hartman
parent 42203e004d
commit 0a6c0fc1f8

View File

@@ -5420,9 +5420,10 @@ int register_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
/* Make a copy hash to place the new and the old entries in */ /* Make a copy hash to place the new and the old entries in */
size = hash->count + direct_functions->count; size = hash->count + direct_functions->count;
if (size > 32) size = fls(size);
size = 32; if (size > FTRACE_HASH_MAX_BITS)
new_hash = alloc_ftrace_hash(fls(size)); size = FTRACE_HASH_MAX_BITS;
new_hash = alloc_ftrace_hash(size);
if (!new_hash) if (!new_hash)
goto out_unlock; goto out_unlock;