From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f179.google.com (mail-qt1-f179.google.com [209.85.160.179]) (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 15C9943C05E for ; Tue, 14 Jul 2026 18:33:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784054030; cv=none; b=s18LJ/7po2HPeV2/pUs2XR6A2tfS1YLJBiOP2FTwKfjoK0vSy6KWKbq/pUhXTxx4iK1RwcSu5UNsWF90bnL7xargLxwnRj0XaaCEDrGigDyZl+NPPBW5kIqOzpsxolGDMZIRq9glkRDUN8b6EM5vPDBKdOV2r6S4QWBpqMUIxEM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784054030; c=relaxed/simple; bh=Gepv4EN5M9EKzOk4KnO+Ro5NR/FnPnIzfUYyZrSuJpA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AQ9TwtnHdkjzpTuz9hvO/jV7OtcaxgZjtkPmBiugIcdEKMtN29OoT70Xk716YfevJGDYJJFC4iNDd7AX6G1zWs8MzLBXmgWD7l7ZbWysPSOAu953IK9gXuodYVfOrxJA7ryMu2b2Mg8bjH5htbhvYkCkwPfHKjNrCSvzuzDAogk= 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=J7zLcB3w; arc=none smtp.client-ip=209.85.160.179 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="J7zLcB3w" Received: by mail-qt1-f179.google.com with SMTP id d75a77b69052e-51c08df8513so9482441cf.3 for ; Tue, 14 Jul 2026 11:33:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784054028; x=1784658828; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=GxRwnz/utPYkA9CVNI0v4sXDVqY3MfYAVIwDwIjJvYI=; b=J7zLcB3w08njHNfoJmJs+2F+DeHDSpqslYrgpytSGPrghruJaV2i2VKhG1yKkNleNT afZdrcAc4+Tz/yXgm5g1HEES+W/BGhXxOxlhiZytrc4Nk9vrFd09IyfPtnNuNDnNCjZg 66/SMchkIcHCjBlXfXafuUEdrXQrjmjfty3a2wOGWBTOP86vWnpjGXytYFMClYDws2tv V9Gskvi4vKycPkEvXarcQzMgjGw6uSD/F2aH0JrLbMtNlHDk6Ud4PJWaXlZAVeObYa0j 70rybAhXbKLrctSKv3eV+AJ8xNp2kHOX3zCvM3xmp4+zzzBZ1SGxF7ntvlVBYYDe5fHj pl9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784054028; x=1784658828; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=GxRwnz/utPYkA9CVNI0v4sXDVqY3MfYAVIwDwIjJvYI=; b=CrFlg9hmeeIXDOsHhBSETpV3P/C0x9jtHQZWGvkX70dqQJnvLKpRnVWscMhoA/21Pc 24yfh7KdLT6pc2pgYGY0vaZNTOgJ2lbvb3/DMjQunuNdrPmjcR7SEBzybhLwz9LI30aS Gg7OcscXBJuxzyX3aTRZq/gaPQECFvEN/w5M/p5WO07Xe3tGkk6tV6o4v0jEUVO7STQz MCJJ0Z9m7JsuUpLUat4GPaMEl/KOF2AS0/3iVZTxkL/I1hxaGK3YBP1yHwytYLarsOU3 B1ugV2VkPoM1skwlkFNTvejNUexxwioH7s6MiRc9w3RHRjeB+HMttJweOpEthAcUKDYA RDTQ== X-Forwarded-Encrypted: i=1; AHgh+Rr7Vi24myCvamaZ4yUdhOHzqGIXw4QqiQND+EUmpmCeezzhVzKlNsR8/tGpxcj/aanoD+dTncWRc3ZhZZCdpL95RGw=@vger.kernel.org X-Gm-Message-State: AOJu0YxgjJUUYP3Zj9y0J3XvCclCYtVKyxQnY+KiV0eT6wk1aAaT4Ycr 07GfDZG65RLU9ZNRK0w/cO4I9XZKQtk83z8KiZzttWSa57dJnyUuSwR3 X-Gm-Gg: AfdE7cnqOhRsbUtldSLEnmNl60nEoekx+PlzIRC9vYCHAx1udzwqLc3Y+l7A0AhmgG1 DpiP/ZnThcFosw9rY2P54LZBLLTMLFcOmb4X88aTzXMWMx73kwGYb4HpSzNG2Gxzw5VTImTA5KW R5Z4k5BO4metFXbYIQL8DufrJkjHlq+sLreBzzHuIYp1j4XQ9xD76irZ0CPZmcRdAMrZSMMKBUi AT7XhTrNMol38DdflVRzv82MRTpbSB1gZ5uP9w1JRf+qTA0k5qy/y8BsbeSvOja+CZ3cAqdaSNJ RZLiXuF9SqhB3W49ADEdjkpRV35erLfTrzI4bsFLY3n0FMGbpwjZbYXNRK7UVHuwrRBUf+udUxA pkofvrDlNBW9hlaQGrDMEKUzHcS1lc4sC3l4PmNwyJYnoK00l+UAZTlHPEERXHePDekyCixacC7 e7dz7dCwr0VWzuGRMlDjYkN5rtr1z0LFyHs2opwMBInjzq6s0OVUk= X-Received: by 2002:a05:622a:993:b0:51b:fe7a:4eb8 with SMTP id d75a77b69052e-51cbf0e8c9emr148137331cf.35.1784054027768; Tue, 14 Jul 2026 11:33:47 -0700 (PDT) Received: from localhost ([48.45.163.146]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8ffd7c1d22bsm173718936d6.32.2026.07.14.11.33.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 14 Jul 2026 11:33:46 -0700 (PDT) From: Jinchao Wang To: Andrew Morton , Peter Zijlstra , Thomas Gleixner , Steven Rostedt , Masami Hiramatsu Cc: Ingo Molnar , Borislav Petkov , Dave Hansen , "H . Peter Anvin" , x86@kernel.org, Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Mathieu Desnoyers , David Hildenbrand , Jonathan Corbet , Matthew Wilcox , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-doc@vger.kernel.org, Jinchao Wang Subject: [RFC PATCH 12/13] mm/kwatch: add KUnit tests for the watch expression parser Date: Wed, 15 Jul 2026 02:33:39 +0800 Message-ID: <20260714183339.13044-1-wangjinchao600@gmail.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260714182243.10687-1-wangjinchao600@gmail.com> References: <20260714182243.10687-1-wangjinchao600@gmail.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Cover base anchors (stack, argN, absolute address), positive and negative offsets, dereference chains, and rejection of malformed expressions (missing offsets, bad argument index, junk offsets). Signed-off-by: Jinchao Wang --- mm/kwatch/.kunitconfig | 9 +++ mm/kwatch/Kconfig | 10 +++ mm/kwatch/Makefile | 1 + mm/kwatch/deref_test.c | 137 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 157 insertions(+) create mode 100644 mm/kwatch/.kunitconfig create mode 100644 mm/kwatch/deref_test.c diff --git a/mm/kwatch/.kunitconfig b/mm/kwatch/.kunitconfig new file mode 100644 index 000000000000..7e977ddf0da1 --- /dev/null +++ b/mm/kwatch/.kunitconfig @@ -0,0 +1,9 @@ +CONFIG_KUNIT=y +CONFIG_KWATCH=y +CONFIG_KWATCH_KUNIT_TEST=y +CONFIG_PERF_EVENTS=y +CONFIG_HAVE_HW_BREAKPOINT=y +CONFIG_HAVE_REINSTALL_HW_BREAKPOINT=y +CONFIG_KPROBES=y +CONFIG_KRETPROBES=y +CONFIG_PRINTK=y diff --git a/mm/kwatch/Kconfig b/mm/kwatch/Kconfig index b1c37a829dd5..74083040a1a3 100644 --- a/mm/kwatch/Kconfig +++ b/mm/kwatch/Kconfig @@ -15,3 +15,13 @@ config KWATCH exact instruction causing the illegal access. If unsure, say N. + +config KWATCH_KUNIT_TEST + bool "KUnit tests for KWatch" if !KUNIT_ALL_TESTS + depends on KWATCH && KUNIT + default KUNIT_ALL_TESTS + help + Enable KUnit tests for the KWatch kernel module. + This suite tests the core parsing logic, the pointer-chasing + finite state machine, and edge cases involving complex watchpoint + expressions. If unsure, say N. diff --git a/mm/kwatch/Makefile b/mm/kwatch/Makefile index 02d7917602f1..1d223d73b461 100644 --- a/mm/kwatch/Makefile +++ b/mm/kwatch/Makefile @@ -1,3 +1,4 @@ obj-$(CONFIG_KWATCH) += kwatch.o kwatch-y := core.o deref.o task_ctx.o hwbp.o probe.o anchor.o +kwatch-$(CONFIG_KWATCH_KUNIT_TEST) += deref_test.o diff --git a/mm/kwatch/deref_test.c b/mm/kwatch/deref_test.c new file mode 100644 index 000000000000..094b7afeb235 --- /dev/null +++ b/mm/kwatch/deref_test.c @@ -0,0 +1,137 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include "kwatch.h" +#include + +static void kwatch_test_parse_deref_chain(struct kunit *test) +{ + struct kwatch_config cfg; + int ret; + + // Test 1: stack + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "stack"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_STACK); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 1); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 0); + + // Test 2: arg1 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg1"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG1); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 1); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 0); + + // Test 3: arg6+8 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg6+8"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG6); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 1); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 8); + + // Test 4: arg2-16 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg2-16"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG2); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 1); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], -16); + + // Test 5: arg3->8 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg3->8"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG3); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 2); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 0); + KUNIT_EXPECT_EQ(test, cfg.offsets[1], 8); + + // Test 6: arg4+8->16 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg4+8->16"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG4); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 2); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 8); + KUNIT_EXPECT_EQ(test, cfg.offsets[1], 16); + + // Test 7: arg5-8->-16 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg5-8->-16"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG5); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 2); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], -8); + KUNIT_EXPECT_EQ(test, cfg.offsets[1], -16); + + // Test 8: stack->0->8 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "stack->0->8"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_STACK); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 3); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 0); + KUNIT_EXPECT_EQ(test, cfg.offsets[1], 0); + KUNIT_EXPECT_EQ(test, cfg.offsets[2], 8); + + // Test 9: arg1->+8 + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg1->+8"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ARG1); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 2); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 0); + KUNIT_EXPECT_EQ(test, cfg.offsets[1], 8); + + // Test 9.1: arg1-> (implicit 0 should fail) + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg1->"); + KUNIT_EXPECT_EQ(test, ret, -EINVAL); + + // Test 9.2: stack->->8 (implicit 0 should fail) + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "stack->->8"); + KUNIT_EXPECT_EQ(test, ret, -EINVAL); + + // Test 10: Invalid base + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "invalid_base"); + KUNIT_EXPECT_EQ(test, ret, -EINVAL); + + // Test 11: Invalid offset + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg1+abc"); + KUNIT_EXPECT_EQ(test, ret, -EINVAL); + + // Test 12: Invalid arg + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "arg7"); + KUNIT_EXPECT_EQ(test, ret, -EINVAL); + + // Test 13: Absolute address + memset(&cfg, 0, sizeof(cfg)); + ret = kwatch_deref_parse(&cfg, "0xffffffff81000000+8"); + KUNIT_EXPECT_EQ(test, ret, 0); + KUNIT_EXPECT_EQ(test, cfg.base, KWATCH_BASE_ABS_ADDR); + KUNIT_EXPECT_EQ(test, cfg.sym_addr, 0xffffffff81000000UL); + KUNIT_EXPECT_EQ(test, cfg.offset_count, 1); + KUNIT_EXPECT_EQ(test, cfg.offsets[0], 8); +} + +static struct kunit_case kwatch_deref_test_cases[] = { + KUNIT_CASE(kwatch_test_parse_deref_chain), + {} +}; + +static struct kunit_suite kwatch_deref_test_suite = { + .name = "kwatch_deref", + .test_cases = kwatch_deref_test_cases, +}; + +kunit_test_suite(kwatch_deref_test_suite); + +MODULE_DESCRIPTION("KUnit tests for the KWatch watch expression parser"); +MODULE_LICENSE("GPL"); -- 2.53.0