TWxSoftware/twx-linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

bpf: Use RCU in all users of __module_text_address().

Browse Source 
__module_address() can be invoked within a RCU section, there is no
requirement to have preemption disabled.

Replace the preempt_disable() section around __module_address() with
RCU.

Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matt Bobrowski <mattbobrowski@google.com>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: bpf@vger.kernel.org
Cc: linux-trace-kernel@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20250129084751.tH6iidUO@linutronix.de
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
This commit is contained in:
Sebastian Andrzej Siewior
2025-01-29 09:47:51 +01:00
committed by Petr Pavlu
parent 72ee1c20b0
commit 8c6eb7ca86
1 changed files with 13 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files
kernel/trace/bpf_trace.c
+13 -11
View File
@@ -2345,10 +2345,9 @@ void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
{
struct module *mod;
preempt_disable();
guard(rcu)();
mod = __module_address((unsigned long)btp);
module_put(mod);
preempt_enable();
}
static __always_inline
@@ -2932,18 +2931,21 @@ static int get_modules_for_addrs(struct module ***mods, unsigned long *addrs, u3
u32 i, err = 0;
for (i = 0; i < addrs_cnt; i++) {
bool skip_add = false;
struct module *mod;
preempt_disable();
mod = __module_address(addrs[i]);
/* Either no module or we it's already stored */
if (!mod || has_module(&arr, mod)) {
preempt_enable();
continue;
scoped_guard(rcu) {
mod = __module_address(addrs[i]);
/* Either no module or it's already stored */
if (!mod || has_module(&arr, mod)) {
skip_add = true;
break; /* scoped_guard */
}
if (!try_module_get(mod))
err = -EINVAL;
}
if (!try_module_get(mod))
err = -EINVAL;
preempt_enable();
if (skip_add)
continue;
if (err)
break;
err = add_module(&arr, mod);