From patchwork Mon Aug 9 09:18:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Almbladh X-Patchwork-Id: 494885 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UPPERCASE_50_75, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 92FB6C4320A for ; Mon, 9 Aug 2021 09:19:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7893361055 for ; Mon, 9 Aug 2021 09:19:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234457AbhHIJTt (ORCPT ); Mon, 9 Aug 2021 05:19:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234323AbhHIJTL (ORCPT ); Mon, 9 Aug 2021 05:19:11 -0400 Received: from mail-ej1-x636.google.com (mail-ej1-x636.google.com [IPv6:2a00:1450:4864:20::636]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4D0E5C06179C for ; Mon, 9 Aug 2021 02:18:51 -0700 (PDT) Received: by mail-ej1-x636.google.com with SMTP id u3so27781396ejz.1 for ; Mon, 09 Aug 2021 02:18:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=anyfinetworks-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=tE7n/SwsfwFALCmJtV/Oui8fCqU+mgVKIR+of1apWuY=; b=yyXzT51bN/dMpHqEUxUqij3m+wS/ufGTNtWe7eTTKt7H3bfWaaBmJe4BkTxWiXy+uO AU2+2CzdM6tKu+t4SwcoJCDo6YchLjTE7vWQqhAmj4Mr6W8Vd9RCszL2DGR/fmFuJIqR eAV7NoYtDvLgwG39kmVQz+NR4yvq255deG1USTgx22BZppqdJBYjIH3Kcr20IaEVg3uB eWbdmvnupUAH6hjPI6lYxa59DGFsDAdb0/gF00OfhhEPvRE+SG8NuDcr5w9k1aQ6eYLf 5fXLJwkfBzyWbDO4Ew66PRsx8t56t652CqGlmL2W2u2flobxRsBuoJ71Z+/SPFDAe3lS jmJg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=tE7n/SwsfwFALCmJtV/Oui8fCqU+mgVKIR+of1apWuY=; b=b6/nKDw3y+nfaPduu8oxGEFFZ8zD4rFqPtJZ6obu3Vilg+jQsNqFn8Rx/g4R9QXhDr VSoQAQ76hCFA0J7cPKdCp5Uv7RUrKsWVCCYOsJLdUKbQkCyDvz6RCp5RK0F/01FnFIln ep7OPdbSrYBmoIkhI17yHj/mafZCLE3nFCkVXNKX4bmiW53VsbTBorbUecg+iv2SnUta n6/ki28VVYwt/VOYr1xD3k/3wU4cev5VL8ApxAJ30Ml8+DkbX1aP00Hn0mNxSBSscqOS BebXONuS9bz3hWRUl28ODx/YgrA8CLArT+jvRM4naUaMbgUgeMx75gGRZuZYI71LylEL y6PQ== X-Gm-Message-State: AOAM533EE4jwBVyRHmQ1z8ircjBjAvDxn9tOlzTk1messVmv2xSe2QP4 UXUr+hXvkQkWxZZomPGVbFpdMA== X-Google-Smtp-Source: ABdhPJxHcJfgKnu4AjZig9pA+iF+2Cv+BYEWCbR1A6viyv5LmKRAyFektjd0D4v4FUnVgAhxuefAFQ== X-Received: by 2002:a17:906:134a:: with SMTP id x10mr21201810ejb.70.1628500729903; Mon, 09 Aug 2021 02:18:49 -0700 (PDT) Received: from anpc2.lan (static-213-115-136-2.sme.telenor.se. [213.115.136.2]) by smtp.gmail.com with ESMTPSA id dg24sm1234250edb.6.2021.08.09.02.18.48 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 09 Aug 2021 02:18:49 -0700 (PDT) From: Johan Almbladh To: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org Cc: kafai@fb.com, songliubraving@fb.com, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, Tony.Ambardar@gmail.com, netdev@vger.kernel.org, bpf@vger.kernel.org, Johan Almbladh Subject: [PATCH bpf-next v2 08/14] bpf/tests: Add tests for ALU operations implemented with function calls Date: Mon, 9 Aug 2021 11:18:23 +0200 Message-Id: <20210809091829.810076-9-johan.almbladh@anyfinetworks.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210809091829.810076-1-johan.almbladh@anyfinetworks.com> References: <20210809091829.810076-1-johan.almbladh@anyfinetworks.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 32-bit JITs may implement complex ALU64 instructions using function calls. The new tests check aspects related to this, such as register clobbering and register argument re-ordering. Signed-off-by: Johan Almbladh --- lib/test_bpf.c | 141 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 141 insertions(+) diff --git a/lib/test_bpf.c b/lib/test_bpf.c index 072f9c51bd9b..e3c256963020 100644 --- a/lib/test_bpf.c +++ b/lib/test_bpf.c @@ -1916,6 +1916,147 @@ static struct bpf_test tests[] = { { }, { { 0, -1 } } }, + { + /* + * Register (non-)clobbering test, in the case where a 32-bit + * JIT implements complex ALU64 operations via function calls. + * If so, the function call must be invisible in the eBPF + * registers. The JIT must then save and restore relevant + * registers during the call. The following tests check that + * the eBPF registers retain their values after such a call. + */ + "INT: Register clobbering, R1 updated", + .u.insns_int = { + BPF_ALU32_IMM(BPF_MOV, R0, 0), + BPF_ALU32_IMM(BPF_MOV, R1, 123456789), + BPF_ALU32_IMM(BPF_MOV, R2, 2), + BPF_ALU32_IMM(BPF_MOV, R3, 3), + BPF_ALU32_IMM(BPF_MOV, R4, 4), + BPF_ALU32_IMM(BPF_MOV, R5, 5), + BPF_ALU32_IMM(BPF_MOV, R6, 6), + BPF_ALU32_IMM(BPF_MOV, R7, 7), + BPF_ALU32_IMM(BPF_MOV, R8, 8), + BPF_ALU32_IMM(BPF_MOV, R9, 9), + BPF_ALU64_IMM(BPF_DIV, R1, 123456789), + BPF_JMP_IMM(BPF_JNE, R0, 0, 10), + BPF_JMP_IMM(BPF_JNE, R1, 1, 9), + BPF_JMP_IMM(BPF_JNE, R2, 2, 8), + BPF_JMP_IMM(BPF_JNE, R3, 3, 7), + BPF_JMP_IMM(BPF_JNE, R4, 4, 6), + BPF_JMP_IMM(BPF_JNE, R5, 5, 5), + BPF_JMP_IMM(BPF_JNE, R6, 6, 4), + BPF_JMP_IMM(BPF_JNE, R7, 7, 3), + BPF_JMP_IMM(BPF_JNE, R8, 8, 2), + BPF_JMP_IMM(BPF_JNE, R9, 9, 1), + BPF_ALU32_IMM(BPF_MOV, R0, 1), + BPF_EXIT_INSN(), + }, + INTERNAL, + { }, + { { 0, 1 } } + }, + { + "INT: Register clobbering, R2 updated", + .u.insns_int = { + BPF_ALU32_IMM(BPF_MOV, R0, 0), + BPF_ALU32_IMM(BPF_MOV, R1, 1), + BPF_ALU32_IMM(BPF_MOV, R2, 2 * 123456789), + BPF_ALU32_IMM(BPF_MOV, R3, 3), + BPF_ALU32_IMM(BPF_MOV, R4, 4), + BPF_ALU32_IMM(BPF_MOV, R5, 5), + BPF_ALU32_IMM(BPF_MOV, R6, 6), + BPF_ALU32_IMM(BPF_MOV, R7, 7), + BPF_ALU32_IMM(BPF_MOV, R8, 8), + BPF_ALU32_IMM(BPF_MOV, R9, 9), + BPF_ALU64_IMM(BPF_DIV, R2, 123456789), + BPF_JMP_IMM(BPF_JNE, R0, 0, 10), + BPF_JMP_IMM(BPF_JNE, R1, 1, 9), + BPF_JMP_IMM(BPF_JNE, R2, 2, 8), + BPF_JMP_IMM(BPF_JNE, R3, 3, 7), + BPF_JMP_IMM(BPF_JNE, R4, 4, 6), + BPF_JMP_IMM(BPF_JNE, R5, 5, 5), + BPF_JMP_IMM(BPF_JNE, R6, 6, 4), + BPF_JMP_IMM(BPF_JNE, R7, 7, 3), + BPF_JMP_IMM(BPF_JNE, R8, 8, 2), + BPF_JMP_IMM(BPF_JNE, R9, 9, 1), + BPF_ALU32_IMM(BPF_MOV, R0, 1), + BPF_EXIT_INSN(), + }, + INTERNAL, + { }, + { { 0, 1 } } + }, + { + /* + * Test 32-bit JITs that implement complex ALU64 operations as + * function calls R0 = f(R1, R2), and must re-arrange operands. + */ +#define NUMER 0xfedcba9876543210ULL +#define DENOM 0x0123456789abcdefULL + "ALU64_DIV X: Operand register permutations", + .u.insns_int = { + /* R0 / R2 */ + BPF_LD_IMM64(R0, NUMER), + BPF_LD_IMM64(R2, DENOM), + BPF_ALU64_REG(BPF_DIV, R0, R2), + BPF_JMP_IMM(BPF_JEQ, R0, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* R1 / R0 */ + BPF_LD_IMM64(R1, NUMER), + BPF_LD_IMM64(R0, DENOM), + BPF_ALU64_REG(BPF_DIV, R1, R0), + BPF_JMP_IMM(BPF_JEQ, R1, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* R0 / R1 */ + BPF_LD_IMM64(R0, NUMER), + BPF_LD_IMM64(R1, DENOM), + BPF_ALU64_REG(BPF_DIV, R0, R1), + BPF_JMP_IMM(BPF_JEQ, R0, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* R2 / R0 */ + BPF_LD_IMM64(R2, NUMER), + BPF_LD_IMM64(R0, DENOM), + BPF_ALU64_REG(BPF_DIV, R2, R0), + BPF_JMP_IMM(BPF_JEQ, R2, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* R2 / R1 */ + BPF_LD_IMM64(R2, NUMER), + BPF_LD_IMM64(R1, DENOM), + BPF_ALU64_REG(BPF_DIV, R2, R1), + BPF_JMP_IMM(BPF_JEQ, R2, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* R1 / R2 */ + BPF_LD_IMM64(R1, NUMER), + BPF_LD_IMM64(R2, DENOM), + BPF_ALU64_REG(BPF_DIV, R1, R2), + BPF_JMP_IMM(BPF_JEQ, R1, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* R1 / R1 */ + BPF_LD_IMM64(R1, NUMER), + BPF_ALU64_REG(BPF_DIV, R1, R1), + BPF_JMP_IMM(BPF_JEQ, R1, 1, 1), + BPF_EXIT_INSN(), + /* R2 / R2 */ + BPF_LD_IMM64(R2, DENOM), + BPF_ALU64_REG(BPF_DIV, R2, R2), + BPF_JMP_IMM(BPF_JEQ, R2, 1, 1), + BPF_EXIT_INSN(), + /* R3 / R4 */ + BPF_LD_IMM64(R3, NUMER), + BPF_LD_IMM64(R4, DENOM), + BPF_ALU64_REG(BPF_DIV, R3, R4), + BPF_JMP_IMM(BPF_JEQ, R3, NUMER / DENOM, 1), + BPF_EXIT_INSN(), + /* Successful return */ + BPF_LD_IMM64(R0, 1), + BPF_EXIT_INSN(), + }, + INTERNAL, + { }, + { { 0, 1 } }, +#undef NUMER +#undef DENOM + }, { "check: missing ret", .u.insns = {