[PATCH v2 bpf-next] bpf: fix a warning message in mark_ptr_not_null_reg()

From: Dan Carpenter <dan.carpenter@oracle.com>
To: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>,
	Andrii Nakryiko <andrii@kernel.org>,
	Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>,
	John Fastabend <john.fastabend@gmail.com>,
	KP Singh <kpsingh@kernel.org>,
	Dmitrii Banshchikov <me@ubique.spb.ru>,
	bpf@vger.kernel.org, linux-kernel@vger.kernel.org,
	kernel-janitors@vger.kernel.org
Subject: [PATCH v2 bpf-next] bpf: fix a warning message in mark_ptr_not_null_reg()
Date: Wed, 17 Feb 2021 10:45:25 +0300	[thread overview]
Message-ID: <YCzJlV3hnF/t1Pk4@mwanda> (raw)
In-Reply-To: <04c60ed2-1a96-2835-9ae1-0ba84f482362@iogearbox.net>

The WARN_ON() argument is a condition, not an error message.  So this
code will print a stack trace but will not print the warning message.
Fix that and also change it to only WARN_ONCE().

Fixes: 4ddb74165ae5 ("bpf: Extract nullable reg type conversion into a helper function")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2:  Use WARN_ONCE().

 kernel/bpf/verifier.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 1dda9d81f12c..3d34ba492d46 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1120,7 +1120,7 @@ static void mark_ptr_not_null_reg(struct bpf_reg_state *reg)
 		reg->type = PTR_TO_RDWR_BUF;
 		break;
 	default:
-		WARN_ON("unknown nullable register type");
+		WARN_ONCE(1, "unknown nullable register type");
 	}
 }
 
-- 
2.30.0

