From nobody Mon Feb 9 17:22:33 2026 Received: from mail-wm1-f41.google.com (mail-wm1-f41.google.com [209.85.128.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 904A523C4E9 for ; Fri, 2 May 2025 10:20:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.41 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746181238; cv=none; b=un8E2DfXMPiKZmicbjJYu5R67Z4TQHx218E9zCekQ6ZRE5D0uqHHsXcSO6YIiCyupz+MiLcxCGVAaiABUPq4SfM0N9359DkhG6kIe7hknwbmobvpLV1weLRoviCgAe+AU3EKes5Ba+1w9J13GYMuxNY9BxAacd3eqaYhetLXNW0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746181238; c=relaxed/simple; bh=ychg/Ta4S8UTx4Xf2MItnvBeDG7XnCP0C93pzW0Ay8Q=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=EgjdKYUIuRZf8M59V01g0x/CJc8EiqottcQv5vYesMSzBNBTslz5Wo7zMpfW4XA0/B3yLFqhOCslgyIqdAxurJkfBl1FHlrVUaP4nxCYSCQI9QA4ADYjKFATOEDgKPv+eUZI5AbIsNTaX45DLZOn4oia5/IX+DHCkaxxd1/CuxA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=isovalent.com; spf=pass smtp.mailfrom=isovalent.com; dkim=pass (2048-bit key) header.d=isovalent.com header.i=@isovalent.com header.b=iFrMq2Kr; arc=none smtp.client-ip=209.85.128.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=isovalent.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=isovalent.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=isovalent.com header.i=@isovalent.com header.b="iFrMq2Kr" Received: by mail-wm1-f41.google.com with SMTP id 5b1f17b1804b1-43cf06eabdaso13969845e9.2 for ; Fri, 02 May 2025 03:20:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=isovalent.com; s=google; t=1746181234; x=1746786034; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=5BATcMPOI1ZCFC5PD+E37IaicFbjrMSjSWMu+X6OAJY=; b=iFrMq2KrEzxnqYfZpYrSkDcrZmSXTm2R2EtCbbwmyYKFjKSIIsFU86nA4vmhJg6ZuN DvnbFMh03gM6vDLUU/Hmo/dk5sY4h3QaiDpLxQYREkUU5q4XMgP2SSaeathVg5CFyQhe avLEtw4z9At7ELVDylYmj2FmgylcgBbpFIxe3PYfv4BHUaggnYgEw//Dmb7Oy26hGvd8 3vUVhp8UTwb+b/38pMJui3OOujpePmtCAXWne/Mf9FGfNca2qzWipt2HbaLAlnthB9tg al9xKIId2v4KV1OijFmaGFnsGNufdTC+8q/DRLEL4csL3IbuuJcUHDlwEyL/gLncbGsn j/FQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1746181234; x=1746786034; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=5BATcMPOI1ZCFC5PD+E37IaicFbjrMSjSWMu+X6OAJY=; b=rCMWMt7+fm1oIrYf4pbHPxoEApvQ0WeT+wwvn3zjNELwDy1XD9jS5cerca5F9NFsJH 3TO2RHue0vlFWH1cfAujOHMZO+MCL8E4hz1RUGCOWSjsaZ+LjBOKCtb3uvbU4aV95uh1 uKoMDwRKkpip8IZJJBNTxgmeniO7ylRzMHYVQEaTCSDuRThL7YQbl5YoEyhiElNTitiD /Kb/NFBWcG6e/k62hAAEryAX/wwyBx0KX8xOsm5WCzzXaJ9gCQH5K0cZgQTR6BB0Zn8H dRmZHelGKJHl8Z7KkMCL6538UJVf56cHurHM3pVdEdHlZhsmvk2qvlXdtjZhQmR+cmhI RnMg== X-Forwarded-Encrypted: i=1; AJvYcCXIiW04iuD2ShMTWjl5FUcrs43k4CTVbuxBQ+ZqAJPaFA0dFA4NNXKa2FR5f0aJzX+xvEPTqsjg32KTL20=@vger.kernel.org X-Gm-Message-State: AOJu0Yzr9JM714YdQCBlr5OVAdpBU3cX8IftdbcMLSScG19StMwBJKq0 pYGS8zYDVB4ETF122UMC1JsozvDt3tlx6TrUuvvAG0Ea09lRsk0zosiGk9u2G2s= X-Gm-Gg: ASbGnctBIruTL8XUu/jhoqI96RTdILI3DQwgZmMBwEGI2ebVOcyrdIbE/6RARE4FKoj V4/QIjbfNGEUY1V2A0gJmD9z2XqPgR3eo0JWwm+WsdsPKjHm1ltQ71Apu599QnR4eVBNXhR5ViJ pXk0VlFfDhRhKjMIxQUPeif7cpXIQNteJb+D3rWTi9io+lcUMdcEYZPGd8l6wf7Et5mZGcylI16 h+mkKRKypTvx8lStXupB4sPUGQwi83mFggw2jtCh9H8g5JK573fvRVNeLRZHDULocfVzFa9/GKO d4ZzMPH+wcuYYCxgRp3bxOuabr2lEdnEiCEH+sytF2mmBkjsy+T69eESfZczrdlGe3smI32GJOF fjgcNk9hKlCJanFe4xcVr3qS+/Uv0YhPftuck X-Google-Smtp-Source: AGHT+IFUHkTtc0DcElXRacw231nP94ZA8KvkgC+j1gjYc5WSrObc75yVcLMxn3UnSEc1kGWDOkoudA== X-Received: by 2002:a05:600c:1e88:b0:43c:fd72:f039 with SMTP id 5b1f17b1804b1-441bbeb3813mr16937805e9.11.1746181233840; Fri, 02 May 2025 03:20:33 -0700 (PDT) Received: from [192.168.1.240] (0.0.6.0.0.0.0.0.0.0.0.0.0.0.0.0.f.f.6.2.a.5.a.7.0.b.8.0.1.0.0.2.ip6.arpa. [2001:8b0:7a5a:26ff::600]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3a099b17017sm1742342f8f.92.2025.05.02.03.20.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 May 2025 03:20:33 -0700 (PDT) From: Lorenz Bauer Date: Fri, 02 May 2025 11:20:06 +0100 Subject: [PATCH bpf-next v2 2/3] selftests: bpf: add a test for mmapable vmlinux BTF Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250502-vmlinux-mmap-v2-2-95c271434519@isovalent.com> References: <20250502-vmlinux-mmap-v2-0-95c271434519@isovalent.com> In-Reply-To: <20250502-vmlinux-mmap-v2-0-95c271434519@isovalent.com> To: Arnd Bergmann , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Mykola Lysenko , Shuah Khan Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, Lorenz Bauer X-Mailer: b4 0.14.2 Add a basic test for the ability to mmap /sys/kernel/btf/vmlinux. Since libbpf doesn't have an API to parse BTF from memory we do some basic sanity checks ourselves. Signed-off-by: Lorenz Bauer --- tools/testing/selftests/bpf/prog_tests/btf_sysfs.c | 82 ++++++++++++++++++= ++++ 1 file changed, 82 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/btf_sysfs.c b/tools/tes= ting/selftests/bpf/prog_tests/btf_sysfs.c new file mode 100644 index 0000000000000000000000000000000000000000..5c8095bedb0517930aabdecc17c= a7043f80f3692 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/btf_sysfs.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause +/* Copyright (c) 2025 Isovalent */ + +#include +#include +#include +#include +#include +#include + +#define BTF_MAGIC 0xeB9F + +static const char *btf_path =3D "/sys/kernel/btf/vmlinux"; + +void test_btf_sysfs(void) +{ + struct stat st; + __u64 btf_size; + void *raw_data =3D NULL; + int fd =3D -1; + size_t trailing; + long page_size; + struct btf *btf =3D NULL; + + page_size =3D sysconf(_SC_PAGESIZE); + if (!ASSERT_GE(page_size, 0, "get_page_size")) + goto cleanup; + + if (!ASSERT_OK(stat(btf_path, &st), "stat_btf")) + goto cleanup; + + btf_size =3D st.st_size; + trailing =3D page_size - (btf_size % page_size) % page_size; + + fd =3D open(btf_path, O_RDONLY); + if (!ASSERT_GE(fd, 0, "open_btf")) + goto cleanup; + + raw_data =3D mmap(NULL, btf_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd= , 0); + if (!ASSERT_EQ(raw_data, MAP_FAILED, "mmap_btf_writable")) + goto cleanup; + + raw_data =3D mmap(NULL, btf_size, PROT_READ, MAP_SHARED, fd, 0); + if (!ASSERT_EQ(raw_data, MAP_FAILED, "mmap_btf_shared")) + goto cleanup; + + raw_data =3D mmap(NULL, btf_size + trailing + 1, PROT_READ, MAP_PRIVATE, = fd, 0); + if (!ASSERT_EQ(raw_data, MAP_FAILED, "mmap_btf_invalid_size")) + goto cleanup; + + raw_data =3D mmap(NULL, btf_size, PROT_READ, MAP_PRIVATE, fd, 0); + if (!ASSERT_NEQ(raw_data, MAP_FAILED, "mmap_btf")) + goto cleanup; + + if (!ASSERT_EQ(mprotect(raw_data, btf_size, PROT_READ | PROT_WRITE), -1, + "mprotect_writable")) + goto cleanup; + + if (!ASSERT_EQ(mprotect(raw_data, btf_size, PROT_READ | PROT_EXEC), -1, + "mprotect_executable")) + goto cleanup; + + /* Check padding is zeroed */ + for (int i =3D 0; i < trailing; i++) { + if (((__u8 *)raw_data)[btf_size + i] !=3D 0) { + PRINT_FAIL("tail of BTF is not zero at page offset %d\n", i); + goto cleanup; + } + } + + btf =3D btf__new(raw_data, btf_size); + if (!ASSERT_NEQ(btf, NULL, "parse_btf")) + goto cleanup; + +cleanup: + if (raw_data && raw_data !=3D MAP_FAILED) + munmap(raw_data, btf_size); + if (btf) + btf__free(btf); + if (fd >=3D 0) + close(fd); +} --=20 2.49.0