bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Ben Dooks <ben.dooks@sifive.com>
To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org
Cc: Sudip Mukherjee <sudip.mukherjee@sifive.com>,
	Jude Onyenegecha <jude.onyenegecha@sifive.com>,
	Ben Dooks <ben.dooks@sifive.com>
Subject: [PATCH] bpf: fix check against plain integer v 'NULL'
Date: Thu, 14 Jul 2022 11:03:22 +0100	[thread overview]
Message-ID: <20220714100322.260467-1-ben.dooks@sifive.com> (raw)

When checking with sparse, btf_show_type_value() is causing a
warning about checking integer vs NULL when the macro is passed
a pointer, due to the 'value != 0' check. Stop sparse complaining
about any type-casting by adding a cast to the typeof(value).

This fixes the following sparse warnings:

kernel/bpf/btf.c:2579:17: warning: Using plain integer as NULL pointer
kernel/bpf/btf.c:2581:17: warning: Using plain integer as NULL pointer
kernel/bpf/btf.c:3407:17: warning: Using plain integer as NULL pointer
kernel/bpf/btf.c:3758:9: warning: Using plain integer as NULL pointer

Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
---
 kernel/bpf/btf.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index eb12d4f705cc..9a6e5f71bbd2 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -1108,7 +1108,8 @@ __printf(2, 3) static void btf_show(struct btf_show *show, const char *fmt, ...)
  */
 #define btf_show_type_value(show, fmt, value)				       \
 	do {								       \
-		if ((value) != 0 || (show->flags & BTF_SHOW_ZERO) ||	       \
+		if ((value) != (__typeof__(value))0 ||			       \
+		    (show->flags & BTF_SHOW_ZERO) ||			       \
 		    show->state.depth == 0) {				       \
 			btf_show(show, "%s%s" fmt "%s%s",		       \
 				 btf_show_indent(show),			       \
-- 
2.35.1


             reply	other threads:[~2022-07-14 10:03 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-14 10:03 Ben Dooks [this message]
2022-07-14 20:28 ` [PATCH] bpf: fix check against plain integer v 'NULL' Yonghong Song
2022-07-15 17:00 ` patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220714100322.260467-1-ben.dooks@sifive.com \
    --to=ben.dooks@sifive.com \
    --cc=bpf@vger.kernel.org \
    --cc=jude.onyenegecha@sifive.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=sudip.mukherjee@sifive.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).