Subject: Re: [PATCH] bpf: reduce compiler warnings by adding fallthrough comments

From: Daniel Borkmann <[email-masked]>
Date: Tue, 14 Feb 2017 00:18:05 +0100

On 02/14/2017 12:02 AM, Alexander Alemayhu wrote:
> Fixes the following warnings:
>
> kernel/bpf/verifier.c: In function ‘may_access_direct_pkt_data’:
> kernel/bpf/verifier.c:702:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
>     if (t == BPF_WRITE)
>        ^
> kernel/bpf/verifier.c:704:2: note: here
>    case BPF_PROG_TYPE_SCHED_CLS:
>    ^~~~
> kernel/bpf/verifier.c: In function ‘reg_set_min_max_inv’:
> kernel/bpf/verifier.c:2057:23: warning: this statement may fall through [-Wimplicit-fallthrough=]
>     true_reg->min_value = 0;
>     ~~~~~~~~~~~~~~~~~~~~^~~
> kernel/bpf/verifier.c:2058:2: note: here
>    case BPF_JSGT:
>    ^~~~
> kernel/bpf/verifier.c:2068:23: warning: this statement may fall through [-Wimplicit-fallthrough=]
>     true_reg->min_value = 0;
>     ~~~~~~~~~~~~~~~~~~~~^~~
> kernel/bpf/verifier.c:2069:2: note: here
>    case BPF_JSGE:
>    ^~~~
> kernel/bpf/verifier.c: In function ‘reg_set_min_max’:
> kernel/bpf/verifier.c:2009:24: warning: this statement may fall through [-Wimplicit-fallthrough=]
>     false_reg->min_value = 0;
>     ~~~~~~~~~~~~~~~~~~~~~^~~
> kernel/bpf/verifier.c:2010:2: note: here
>    case BPF_JSGT:
>    ^~~~
> kernel/bpf/verifier.c:2019:24: warning: this statement may fall through [-Wimplicit-fallthrough=]
>     false_reg->min_value = 0;
>     ~~~~~~~~~~~~~~~~~~~~~^~~
> kernel/bpf/verifier.c:2020:2: note: here
>    case BPF_JSGE:
>    ^~~~
>
> Reported-by: David Binderman <[email-masked]>
> Signed-off-by: Alexander Alemayhu <[email-masked]>

These fall-through comments are fine for net-next tree.

Acked-by: Daniel Borkmann <[email-masked]>