From nobody Sat Jul 25 00:04:15 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CA7542DB7B8; Wed, 22 Jul 2026 01:51:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784685119; cv=none; b=U4mdsJ/GLCVLcG4Pm0cLWgaQH2Vyp4rMKHH/xIyt3XrQrqwBN5+4FY5KNt+z2ceg1/I3fzQooz/dTPvWXJoY9ViwjjXjRiVAXqx9PDoMGfyaE6H7Mz86gvFPtXgAtpeMBP/ZowdOv48bL/mtOIskjfTRsf6TNHZKfzOzsE46JNw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784685119; c=relaxed/simple; bh=XqR56W7gJTWXbzpBfGpKMJyhOg6Q0hmyudlcq6Hsz8k=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=PotqtqpIO3iUab86p6GT71DFV9SRpGT2niXkA+rARndPrbWCISWyX+fiIuMGp+9Gs+HtKMAILeQn5j82JjDNSnkVl5mSlEgT3o65/RVkwa1YHISiwKYxrAxRVLV6MUWCPF31ZOKaf6qghKIcxwfCuqFU4/f05cQfAfz9kfbSdGs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: e66927be856f11f1aa26b74ffac11d73-20260722 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:700017f1-09f0-4f90-87fb-c3274a4720b5,IP:0,U RL:0,TC:0,Content:-5,EDM:25,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:20 X-CID-META: VersionHash:e7bac3a,CLOUDID:e8fe7246ed586caeb3be2055202cf609,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:102|136|850|865|898,TC:nil,Content:0|15| 50,EDM:5,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI:0, OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: e66927be856f11f1aa26b74ffac11d73-20260722 X-User: yanlonglong@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 270753574; Wed, 22 Jul 2026 09:51:47 +0800 From: longlong yan To: pabeni@redhat.com, kuba@kernel.org, davem@davemloft.net Cc: edumazet@google.com, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, shuah@kernel.org, horms@kernel.org, longlong yan Subject: [PATCH] selftests/net: use MAP_FAILED instead of (void *)-1 in tcp_mmap Date: Wed, 22 Jul 2026 09:51:29 +0800 Message-ID: <20260722015129.916-1-yanlonglong@kylinos.cn> X-Mailer: git-send-email 2.47.1.windows.2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" mmap() is documented to return MAP_FAILED on error, but tcp_mmap.c compares the return value against (void *)-1 and (unsigned char *)-1. Replace these with the standard MAP_FAILED macro for better readability and type safety. Signed-off-by: longlong yan Reviewed-by: Eric Dumazet Reviewed-by: Joe Damato --- tools/testing/selftests/net/tcp_mmap.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/net/tcp_mmap.c b/tools/testing/selftes= ts/net/tcp_mmap.c index 2544ae35d07a..487ae659a1f1 100644 --- a/tools/testing/selftests/net/tcp_mmap.c +++ b/tools/testing/selftests/net/tcp_mmap.c @@ -141,12 +141,12 @@ static void *mmap_large_buffer(size_t need, size_t *a= llocated) buffer =3D mmap(NULL, sz, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0); =20 - if (buffer =3D=3D (void *)-1) { + if (buffer =3D=3D MAP_FAILED) { sz =3D need; buffer =3D mmap(NULL, sz, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_POPULATE, -1, 0); - if (buffer !=3D (void *)-1) + if (buffer !=3D MAP_FAILED) fprintf(stderr, "MAP_HUGETLB attempt failed, look at /sys/kernel/mm/hug= epages for optimal performance\n"); } *allocated =3D sz; @@ -189,13 +189,13 @@ void *child_thread(void *arg) =20 fcntl(fd, F_SETFL, O_NDELAY); buffer =3D mmap_large_buffer(chunk_size, &buffer_sz); - if (buffer =3D=3D (void *)-1) { + if (buffer =3D=3D MAP_FAILED) { perror("mmap"); goto error; } if (zflg) { raddr =3D mmap(NULL, chunk_size + map_align, PROT_READ, flags, fd, 0); - if (raddr =3D=3D (void *)-1) { + if (raddr =3D=3D MAP_FAILED) { perror("mmap"); zflg =3D 0; } else { @@ -547,7 +547,7 @@ int main(int argc, char *argv[]) } =20 buffer =3D mmap_large_buffer(chunk_size, &buffer_sz); - if (buffer =3D=3D (unsigned char *)-1) { + if (buffer =3D=3D MAP_FAILED) { perror("mmap"); exit(1); } --=20 2.43.0