Subject: [PATCH 13/18] bpf: Return error value in bpf_dispatcher_update

From: Jiri Olsa <[email-masked]>
Date: Sun, 16 Feb 2020 20:30:00 +0100

We don't currently propagate error value from
bpf_dispatcher_update function. This will be
needed in following patch, that needs to update
kallsyms based on the success of dispatcher
update.

Suggested-by: Andrii Nakryiko <[email-masked]>
Signed-off-by: Jiri Olsa <[email-masked]>
---
 kernel/bpf/dispatcher.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/kernel/bpf/dispatcher.c b/kernel/bpf/dispatcher.c
index b3e5b214fed8..3a5871bbd6d0 100644
--- a/kernel/bpf/dispatcher.c
+++ b/kernel/bpf/dispatcher.c
@@ -102,7 +102,7 @@ static int bpf_dispatcher_prepare(struct bpf_dispatcher *d, void *image)
 	return arch_prepare_bpf_dispatcher(image, &ips[0], d->num_progs);
 }
 
-static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs)
+static int bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs)
 {
 	void *old, *new;
 	u32 noff;
@@ -118,15 +118,17 @@ static void bpf_dispatcher_update(struct bpf_dispatcher *d, int prev_num_progs)
 
 	new = d->num_progs ? d->image + noff : NULL;
 	if (new) {
-		if (bpf_dispatcher_prepare(d, new))
-			return;
+		err = bpf_dispatcher_prepare(d, new);
+		if (err)
+			return err;
 	}
 
 	err = bpf_arch_text_poke(d->func, BPF_MOD_JUMP, old, new);
 	if (err || !new)
-		return;
+		return err;
 
 	d->image_off = noff;
+	return 0;
 }
 
 void bpf_dispatcher_change_prog(struct bpf_dispatcher *d, struct bpf_prog *from,
-- 
2.24.1