From patchwork Wed Aug 21 09:09:18 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Ambardar X-Patchwork-Id: 13771101 Received: from mail-pl1-f178.google.com (mail-pl1-f178.google.com [209.85.214.178]) (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 6E1F91A284A; Wed, 21 Aug 2024 09:09:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.178 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724231385; cv=none; b=T6+ChN4M+X7n1o0edIpWijuLezRLn2ciSTv01eE15JV0EGI5WIj8NBxqxjnsCGo2IDzOdoNXlRfVPAAqaXzUIs2bc4QbPIF91FUCuACtIuEHkYjD3Rm1GBzK1gHD9xhyeHe2A7gejLot9qAs6XHt1/CnNBYJQYEi1iyoMUOtF7E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724231385; c=relaxed/simple; bh=jItsKl48G4HoacL29xhAgJj4C5vLekKV/E7V7Qii9S4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=uCAOMdieR0XLHyDurMe5CmGaW5WCy5cN/vYNyTfmze7decnrzupM+9BtKe8S5NkSfsfuVDjHNmi2jFtcC+dP7wibhLfaRfZ/JLAyLJNnYi8ar8aqjzc46fdrEsG/Sr3QFclxB4LwA8PA/lRdNLtZwiZG/r37Ur+uBOPaK2dcFJg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=YK6iMP8a; arc=none smtp.client-ip=209.85.214.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YK6iMP8a" Received: by mail-pl1-f178.google.com with SMTP id d9443c01a7336-20227ba378eso31374505ad.0; Wed, 21 Aug 2024 02:09:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1724231383; x=1724836183; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=L6TlrI1/hqehlwT1+UXhIaV4LOdcr7ZDugFdaqdnHRc=; b=YK6iMP8a++9ilvXLBYMk6joi+lVlSIli7pKPz4FQiA5O+JE4yU8/vjPkHZBlDAApht 5Y+3yyd03p0KS5dSPHh4J8pAgpjYPHRtg2rnWh9Vj16l7zkO6N7meVpOSb/S29AuXGEG fLrgk4Zvv/lYuO9MC03IFuvvTL4X8hvNz3a59z0Ohs4YRyO+kyEMfJb2L4XX5HyhM/CJ 75iPq28FOPvMK1PT8ZQZQWUJt1yZK+0g+vVYQdfgE+w1g8RCNOapV33wAqhiE80HlEUf jJ+7PObES0GoiPdKUO/bn+Lo3MUXL+x2/B1MYqBasbiddmrPfzcoWZ5nzRzawKLQy1nZ FnqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1724231383; x=1724836183; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=L6TlrI1/hqehlwT1+UXhIaV4LOdcr7ZDugFdaqdnHRc=; b=f43z0RPxzscIIyrltvzCocShipcYCOC6i34uRs7uXGSSGZn2UmnlG8W6QeaQMkWXu7 vtbT8mssouBdffAIFzuywl/uXhu1KIsZIQaDdcFsHTQdIDlrIPwsnIfo0TeKK4qTSsd6 Oxo44q+AxMn0IKhSmkwbNUw0eab9oQ7mQHa3hhzXd/i8PMQKmWwLg1wEHnt4SICZwbAh SJkrvdBwzIkF50H3MprUIZuvHCmQ0QmcrlcDHoOAjik3Wqi4LOPvuBYXUZ8K3iWqju5P WD+X8zmJo78cguiAs8ZZVfUMHWK0ZgddJzTzS+IuKhn71BtuKdUSkYfCLn2DazRbs7sN jiew== X-Forwarded-Encrypted: i=1; AJvYcCX/XLmVtMlxJzFsPUcvnpx83PjlyZXTS8e1XqknDj7scGtIe5PXfhkiClwr7FkGLE4wJzpMotdDgkaSwZdYEfA=@vger.kernel.org X-Gm-Message-State: AOJu0Yx02I5K+iKpoUuSOBNSJGLIapNnscaxbShonCJVi4QffYucQ0M2 j9hUwoyNqrd/t190OGpq1Q94HDp3SirtRwNYl2mmdeo5e7v4E5m51i9det2O X-Google-Smtp-Source: AGHT+IHzb7nc6m6ZvtWkvuuaiJyGDWXiVwuH/sMqDdtlEYgziLv0hatT6M5q7BXoC/3idsagqCu3tg== X-Received: by 2002:a17:902:ec83:b0:1fb:973f:866 with SMTP id d9443c01a7336-2036819f6a4mr14720415ad.52.1724231383408; Wed, 21 Aug 2024 02:09:43 -0700 (PDT) Received: from localhost.localdomain (69-172-146-21.cable.teksavvy.com. [69.172.146.21]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-201f031c5e1sm90191405ad.94.2024.08.21.02.09.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Aug 2024 02:09:42 -0700 (PDT) From: Tony Ambardar To: bpf@vger.kernel.org Cc: Tony Ambardar , linux-kselftest@vger.kernel.org, Andrii Nakryiko , Eduard Zingerman , Alexei Starovoitov , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Mykola Lysenko , Shuah Khan , Ilya Leoshkevich Subject: [PATCH bpf-next v1 0/8] libbpf, selftests/bpf: Support cross-endian usage Date: Wed, 21 Aug 2024 02:09:18 -0700 Message-Id: X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Hello all, This patch series targets a long-standing BPF usability issue - the lack of general cross-compilation support - by enabling cross-endian usage of libbpf and cross-endian build targets for selftests/bpf. Use cases range from better BPF support for embedded systems based on e.g. big-endian MIPS, to more build/test options for s390x systems. Initial development and testing used mips64, since this arch makes switching the build byte-order trivial and is thus very handy for A/B testing. However, it lacks some key features (bpf2bpf call, kfuncs, etc) making for poor selftests/bpf coverage. Final testing takes the kernel and selftests/bpf cross-built from x86_64 to s390x, and runs the result under QEMU/s390x. That same configuration could also be used on kernel-patches/bpf CI for regression testing endian support or perhaps load-sharing s390x builds across x86_64 systems. This thread includes some background regarding testing on QEMU/s390x and the generally favourable results (3 failures running test_progs): https://lore.kernel.org/bpf/ZsEcsaa3juxxQBUf@kodidev-ubuntu/ Feedback and suggestions are welcome! Best regards, Tony Tony Ambardar (8): libbpf: Improve log message formatting libbpf: Fix header comment typos for BTF.ext libbpf: Fix output .symtab byte-order during linking libbpf: Support BTF.ext loading and output in either endianness libbpf: Support opening bpf objects of either endianness libbpf: Support linking bpf objects of either endianness libbpf: Support creating light skeleton of either endianness selftests/bpf: Support cross-endian building tools/lib/bpf/bpf_gen_internal.h | 1 + tools/lib/bpf/btf.c | 167 +++++++++++++++++++++++-- tools/lib/bpf/btf.h | 2 + tools/lib/bpf/btf_dump.c | 2 +- tools/lib/bpf/btf_relocate.c | 2 +- tools/lib/bpf/gen_loader.c | 179 +++++++++++++++++++++------ tools/lib/bpf/libbpf.c | 26 +++- tools/lib/bpf/libbpf.map | 2 + tools/lib/bpf/libbpf_internal.h | 17 ++- tools/lib/bpf/linker.c | 108 +++++++++++++--- tools/lib/bpf/relo_core.c | 2 +- tools/lib/bpf/skel_internal.h | 3 +- tools/testing/selftests/bpf/Makefile | 7 +- 13 files changed, 438 insertions(+), 80 deletions(-)