From patchwork Fri Jan 13 09:09:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Tissoires X-Patchwork-Id: 13100312 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 801EAC54EBD for ; Fri, 13 Jan 2023 09:12:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241118AbjAMJMM (ORCPT ); Fri, 13 Jan 2023 04:12:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235363AbjAMJMC (ORCPT ); Fri, 13 Jan 2023 04:12:02 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7044938C for ; Fri, 13 Jan 2023 01:09:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1673600985; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=X4OMapMn4DPgQ6a+VqmEJlLUwkXj3/OngbIshLVda8U=; b=TtUVPtWnnN87PUcIZ0SOYL4gWxqHv2dHdAuokZm34KTtXQ7uKhmj/ZkFb5dGJNVa5yFY4s rCbSxw3Bjri1pDy/tLU+BKecQfIUXNpdZxskAzUgutVh8RfP1d1N5eaiNXlACoDoHU4s+n wFA49rG7zyAAV83r/agZVtny4jyJ/W4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-577-hrpH9WwZOmmcyoABtpkYUQ-1; Fri, 13 Jan 2023 04:09:40 -0500 X-MC-Unique: hrpH9WwZOmmcyoABtpkYUQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id BA3C6858F0E; Fri, 13 Jan 2023 09:09:39 +0000 (UTC) Received: from plouf.redhat.com (ovpn-193-50.brq.redhat.com [10.40.193.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 529D11121314; Fri, 13 Jan 2023 09:09:37 +0000 (UTC) From: Benjamin Tissoires To: Greg KH , Jiri Kosina , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Dmitry Torokhov Cc: Tero Kristo , linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org, Benjamin Tissoires Subject: [PATCH HID for-next v2 0/9] HID-BPF LLVM fixes, no more hacks Date: Fri, 13 Jan 2023 10:09:26 +0100 Message-Id: <20230113090935.1763477-1-benjamin.tissoires@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi, So this is the fix for the bug that actually prevented me to integrate HID-BPF in v6.2. While testing the code base with LLVM, I realized that clang was smarter than I expected it to be, and it sometimes inlined a function or not depending on the branch. This lead to segfaults because my current code in linux-next is messing up the bpf programs refcounts assuming that I had enough observability over the kernel. So I came back to the drawing board and realized that what I was missing was exactly a bpf_link, to represent the attachment of a bpf program to a HID device. This is the bulk of the series, in patch 6/9. The other patches are cleanups, tests, and also the addition of the vmtests.sh script I run locally, largely inspired by the one in the bpf selftests dir. This allows very fast development of HID-BPF, assuming we have tests that cover the bugs :) changes in v2: - took Alexei's remarks into account and renamed the indexes into prog_table_index and hid_table_index - fixed unused function as reported by the Intel kbuild bot Cheers, Benjamin Benjamin Tissoires (9): selftests: hid: add vmtest.sh selftests: hid: allow to compile hid_bpf with LLVM selftests: hid: attach/detach 2 bpf programs, not just one selftests: hid: ensure the program is correctly pinned selftests: hid: prepare tests for HID_BPF API change HID: bpf: rework how programs are attached and stored in the kernel selftests: hid: enforce new attach API HID: bpf: clean up entrypoint HID: bpf: reorder BPF registration Documentation/hid/hid-bpf.rst | 12 +- drivers/hid/bpf/entrypoints/entrypoints.bpf.c | 9 - .../hid/bpf/entrypoints/entrypoints.lskel.h | 188 ++++-------- drivers/hid/bpf/hid_bpf_dispatch.c | 28 +- drivers/hid/bpf/hid_bpf_dispatch.h | 3 - drivers/hid/bpf/hid_bpf_jmp_table.c | 129 ++++---- include/linux/hid_bpf.h | 7 + tools/testing/selftests/hid/.gitignore | 1 + tools/testing/selftests/hid/Makefile | 10 +- tools/testing/selftests/hid/config.common | 241 +++++++++++++++ tools/testing/selftests/hid/config.x86_64 | 4 + tools/testing/selftests/hid/hid_bpf.c | 32 +- tools/testing/selftests/hid/progs/hid.c | 13 + tools/testing/selftests/hid/vmtest.sh | 284 ++++++++++++++++++ 14 files changed, 728 insertions(+), 233 deletions(-) create mode 100644 tools/testing/selftests/hid/config.common create mode 100644 tools/testing/selftests/hid/config.x86_64 create mode 100755 tools/testing/selftests/hid/vmtest.sh