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Filtering the boot messages with scripts/dtc/of_unittest_expect detects that the stack dump is expected instead of being a test error. Test beds might interpret the stack dumps as errors, resulting in needless debugging and error reports. These test beds are likely to remove unittests due to these stack dumps. To avoid these problems, have unittest default to skip the tests that trigger a stack dump. Add a kernel cmdline option to not skip those tests. This option can be used by testers who are able to interpret the stack dumps as not an error. Signed-off-by: Frank Rowand --- drivers/of/unittest.c | 54 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 51 insertions(+), 3 deletions(-) diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c index b5a7a31d8bd2..3a9bc2bc4ba1 100644 --- a/drivers/of/unittest.c +++ b/drivers/of/unittest.c @@ -70,6 +70,36 @@ static struct unittest_results { #define EXPECT_NOT_END(level, fmt, ...) \ printk(level pr_fmt("EXPECT_NOT / : ") fmt, ##__VA_ARGS__) +/* + * Some tests will cause the kernel to emit a stack dump, aka back trace, + * when the test is successful. The tests should make it possible for + * test beds to detect that the trace is not an error via EXPECT_BEGIN(). + * + * Most test beds do not process the EXPECT_BEGIN() information and may + * flag the stack dump as an error, thus reporting a false failure. It + * is hoped that the KTAP version 4 specification will add the EXPECT_BEGIN() + * processing to test beds. + * + * By default, skip tests that cause a stack dump. Test beds that process + * EXPECT_BEGIN() information should enable these tests via a kernel boot + * command line option. + */ +static int stackdump_tests_enabled; + +static int __init enable_unittest_stackdump(char *str) +{ + stackdump_tests_enabled = 1; + return 0; +} + +static int __init disable_unittest_stackdump(char *str) +{ + stackdump_tests_enabled = 0; + return 0; +} +early_param("of_unittest_stackdump", enable_unittest_stackdump); +early_param("no_of_unittest_stackdump", disable_unittest_stackdump); + static void __init of_unittest_find_node_by_name(void) { struct device_node *np; @@ -3047,19 +3077,26 @@ static void __init of_unittest_lifecycle(void) of_node_put(np); } + if (!stackdump_tests_enabled) + goto out_skip_stackdump_tests; + EXPECT_BEGIN(KERN_INFO, "OF: ERROR: of_node_release() detected bad of_node_put() on /testcase-data/refcount-node"); /* * refcount is now one, decrementing to zero will result in a call to * of_node_release() to free the node's memory, which should result - * in an error + * in an error. + * + * A refcount of zero will also trigger errors in + * of_unittest_check_node_linkage(), so after this block of test, + * will directly manipulate the devicetree to remove this node. + * (See the code marked as "WARNING: EVIL, EVIL, EVIL:".) */ unittest(1, "/testcase-data/refcount-node is one"); of_node_put(np); EXPECT_END(KERN_INFO, "OF: ERROR: of_node_release() detected bad of_node_put() on /testcase-data/refcount-node"); - /* * expect stack trace for subsequent of_node_put(): * __refcount_sub_and_test() calls: @@ -3138,9 +3175,20 @@ static void __init of_unittest_lifecycle(void) return; +out_skip_stackdump_tests: + /* + * Pass test since we don't yet have a way to annotate reason for an + * intentional skip until implementing the KTAP format. + */ + unittest(1, "Lifecycle stackdump tests skipped\n"); + return; + out_skip_tests: + /* skip is due to an earlier failure */ + unittest(0, "One or more lifecycle tests skipped due to previous fails\n"); +#else + unittest(1, "Lifecycle tests skipped because CONFIG_DYNAMIC=n\n"); #endif - unittest(0, "One or more lifecycle tests skipped\n"); } #ifdef CONFIG_OF_OVERLAY From patchwork Wed Mar 1 01:21:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Frank Rowand X-Patchwork-Id: 62698 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:5915:0:0:0:0:0 with SMTP id v21csp3357688wrd; Tue, 28 Feb 2023 17:24:50 -0800 (PST) X-Google-Smtp-Source: AK7set8J1+PV+n6wF5Nh08geMh8q6VVZVQnINfERWLvuEPxY6GBBA15cU5eDxQcSBH+/ii23pfJN X-Received: by 2002:a17:903:2692:b0:19c:a3be:d9f7 with SMTP id jf18-20020a170903269200b0019ca3bed9f7mr4232636plb.11.1677633889750; Tue, 28 Feb 2023 17:24:49 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1677633889; cv=none; d=google.com; s=arc-20160816; b=AI/RgITjqT7PsroigVuDE+6oWIzx+n42iOmwqkHaDD+ig90OcTninP7Fx3H7AM5QHw 4qQCBkyfNUUmHFv58/XqwNF6Zmrc3771v9ygU4uMpD+WOCdDDZ4NbzCkYB1pijL9Dg3n c1yrkq15YJMme7ATIgOmtxbhZjLDzoF5LqhjtxE8hzSL1i91JadmJ+3rF27QDXY/sWYN 58bmRSRE3usZoiMT/hsQHKdZTJ72/hnhmD+SUJ4Qu81bw304WLbM0deZUq6T1sSobjo4 ri455uUzpKG7uUfmQy7X4haZNIHcWp490y/lqZjQsVa9F79VseALoIrIgnZAL/6WP2wX KIcw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=ut1wOGTxZO1SVGZaQtP1Hekk5rmZBOrU7xQMiC2fKDs=; b=MFSB6e9Uy/oe9psXlu6gtARMkJeST+vI0BQrAXbM6KgmF58kN36UovAZ5j+M7nzlmu Hh6iYvesMsZfuKX2TPC3memQwDE8QZEyfgWIkEoFkcUnIcwv6IOO8dY0Md1XBdv0svlU ysWO8fp735qgNVPeFs7WuY6GB0XI92zSafCGbzFeFG+ZwnehfTGkhPU2Ll5r+M2KDtpT VBGmh+iRwD79TbaDVj0N7+t+2PduzCTrNRx58vPRw5yw2N7Th8DDCWxPoR4xwaZd8Bye Ro90qfLn3Dga4teKAgQUfKhW+JyvDubsnVzBMXoINYMFt7HsjwOtlg/onkXkgHtXAsa2 q1oQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20210112 header.b=W4wRXOLh; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (out1.vger.email. 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Signed-off-by: Frank Rowand --- Documentation/admin-guide/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6221a1d057dd..98c3fc7f4f72 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3911,6 +3911,10 @@ This can be set from sysctl after boot. See Documentation/admin-guide/sysctl/vm.rst for details. + of_unittest_stackdump [OF] + Do not skip OF unittests that trigger a kernel stack dump. + Default: skip the tests that trigger a kernel stack dump + ohci1394_dma=early [HW] enable debugging via the ohci1394 driver. See Documentation/core-api/debugging-via-ohci1394.rst for more info.