From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=209.85.128.53 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793158341; b=BOCB/UtBhPWE+DYblG3lVTKVoOJIz2r7jEKp/yeSgvTebLek50IP6jhioTJLLwCREc3x 9lUnEpjWkih++v5HDHZKOeEm+QAf6iFNLcIKaSG7wROPZpPnO7wJFQHQZjngu7+pGfbgQ cUEkP64ovH1iDJM3MVk9vrkhsOQxp0TSEUfzIAfeyCl46pBjkK1Bo03S/nhmy43XRWBAN Jk1573rSS5H1WwR82Ds6TVskOg7DdCfYwVjVlCvCDvVrpgY4U6oAuGGnWL5vCBCiuUZiz lrktZ9C5tFa7a4XnUbfu1lD7L/PmPRzHgOKWZ6ec4wWvxfZ+8Kko4zi+Bjj+tdQJkSQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793158341; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: From:To:Cc:Subject:Date:Message-Id:X-Mailer:In-Reply-To:References: MIME-Version:Content-Transfer-Encoding; bh=ZR3iK/21HRL590OT/HWs7TggzA8Gmahp8IuVcPxIo1I=; b=2+SyjT930EcYdRYIJV3FZpZFLQpP8UkV9y2dBs33ICHUBBKro9wK4mymMsvasT/RIOJG AL24swtBKtVInMw9HfPiHk3rQPmf/0msKLRHoZJL5fjSPiQtIHmJ2nGmj4U6AAK2ccFIr 3KUEOwXMSTbjd0AI3e4D0gZjNnTQ5XKX8f3Wk4Nozvr4scY8i5bM0r4yJ/Np+yJkMRvEm B/bDkgu/64thAbLt7OGA1UOGfpwZF8CsxZDvq39pexi32zvPBupgOybPjNakA8V9BUMwE Ii6cPhJCnAGaRrF0RPaSp0Qz+3+wly3nqXlniOsFdZ7M6uGwaIoNZdlQjSGyKlHb0MQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=Td9F3R7p; arc=none smtp.remote-ip=209.85.128.53 Received: from mail-wm1-f53.google.com (mail-wm1-f53.google.com [209.85.128.53]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5DA54606A33F for ; Wed, 28 Oct 2026 03:32:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 5DA54606A33F 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, unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=Td9F3R7p Received: by mail-wm1-f53.google.com with SMTP id 5b1f17b1804b1-4a9a8d6cea8so949565e9.1 for ; Tue, 27 Oct 2026 20:32:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1793158340; x=1793763140; 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=ZR3iK/21HRL590OT/HWs7TggzA8Gmahp8IuVcPxIo1I=; b=Td9F3R7pKt9XoyGMCk2tSwEFepXc6mG0UKbjwl4qrQPGswD12MrUnQNew0T0VRdVx7 Z0ASLPwsJAX6QRsg5D6z23EVXQ2Ij7jQvCFtTbdkbwv2ZLCC/x1dqh6Bf1tgIJW8y3zf K8R58PTVmwPzqGUT4lIFqDjBHVlL3f8McSL/ryhcPxOO+n36Tl/svJ7iBjqTIdlIDe8S YORIEupvQ+PVliBwnBmNTvqvHz64J9V4C495f7Pv297tROUMULxaTRDp6OIyJPGQsbeg 6UlwdRVZsD3MQN95UOXuEcpKM9WBvg4sTUemDgeJMG5zEst3NYtyD0tLqVDiikRt2uiG kmNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1793158340; x=1793763140; 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=ZR3iK/21HRL590OT/HWs7TggzA8Gmahp8IuVcPxIo1I=; b=DrL1O0MOq+TnwiZH5I9v0Xc3+QoZRCL6RJEKxk4ww8pOC5w32Wm16qjKClehe6ou1V 9Aq8EVIy5HKzCtR3DCOwH5X12zZYsxCnVFPn/BPm8ZgAPN/8/UZ2w086Z9Gy4buAx7sk oV+q15c5hYI4IpyOPKgcG8I3TToO1aNljXTBp6VQUL36qCWDhl7Dcky1Rza1LrJPoOYj P0GaV0wJxb+J29teEhYUI/CCFDnaJmjpDmhTuvEah4QLoCe55l4aGigJIxFd4NZy4Nb9 qdjvrg1ZYqw0iJUHrUUNeNvDqm+Al8TiCiPFlWgqrK0gWHGSMSadeWEu0EEgS3yD9Cxh bcKw== X-Forwarded-Encrypted: i=1; AKwUvBxfdPp3euPLPGqCr33GLSFngJKtgvKcfAru0hUp1LBm0OFuOqAxol2SCSYts86ERsNcLAj/uq9lcjvdi6IhnGW0qzs=@vger.kernel.org X-Gm-Message-State: AFq9FYLCUiF4Rp5YD5V5OJMbq2q2bYGvUDifWQgmbxvSUK/TZ6bi323X pUYbXdHotDKr5V6y1aPETtgze/GBZKYLF0kLkf14esW4xEPVNs1q2vQ1 X-Gm-Gg: AYBFou2X3omM7SdWvNiZ8qahMJQyresqsXuBdtrQHAI4AtGj92q7AX0PwMwdesWCIvJ a5LRl7pWR4f5mMILBTCTnhgJXptjasvvgGAhMl2cDddTsiivOV42NyaKNZqyauWZAcpSCC8kL/p WgcuEwPybCGeeWpbaxs/oJqiAeRVbQ5/9ZHzyZROgi22dc8xto20c3SjoRCKsQdvsfBFaQV2uD9 M7h6pLYPPmL8oHWMk8xhIDaOMFmQrwidUvTl6yMBaGl+MhRlGIprsFiiosC2Y7a8hWPOeyRqy1A PvD94kz8o1KZWqpzi30JgeX+c2ZvvoUiSY9XcCVMluT3kAUW5u4DyoqRa+t3LvdUtnrSX0/qKSI cTUuH0BJ/OfC0GspMaJPNkxLaZx7n5yfwu+vJpN29Wln2XPe1Sxqpmpyk3eCXGiabeeBqy2w210 1VtrLPPmlJgHw2n/kIoo6tnpjSAS1YsQuH+ZAQUbkIRskb0pyXWJGXkAJ/laB8XvRVUNfu7i9Od 0CdRYqzN+S3mEiKNEmiB8K+dM4eH2RUsxKJxj/P95+OH9jEw5SiLJ6p9ELyJBMjFOUuJdR5QXjX ZB9+sLJYFISEtjcZs7Zsh9T43KnQEtFXUbcUdpB3bMa6o5JYZJVMv2knUWQsm6jfNFpBBbFPUIJ rhNCmd77ajtT0juJii67I3O/5ckrjP2jn4SYXZOutVPHLW0C+y5mHd5m377sFn44WJc2aRGpks1 Rjn5VeoM4KAWmuzhabMBFMsVdgmTWvk7kH X-Received: by 2002:a05:600d:8641:20b0:4a2:10d:5e0d with SMTP id 5b1f17b1804b1-4a7c58f389cmr88355155e9.14.1793158339700; Tue, 27 Oct 2026 20:32:19 -0700 (PDT) Received: from localhost.localdomain (dynamic-2a02-3100-a45b-7d01-5035-b393-698f-53f0.310.pool.telefonica.de. [2a02:3100:a45b:7d01:5035:b393:698f:53f0]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48e3ecdfd8dsm24290569f8f.56.2026.10.27.20.32.17 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Tue, 27 Oct 2026 20:32:19 -0700 (PDT) From: Karl Mehltretter To: Steven Rostedt , Peter Zijlstra , Thomas Gleixner , Sebastian Andrzej Siewior Cc: Karl Mehltretter , Catalin Marinas , Will Deacon , Mark Rutland , Ingo Molnar , Andy Lutomirski , Frederic Weisbecker , "Paul E. McKenney" , Boqun Feng , Waiman Long , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , Hongyan Xia , Jonathan Corbet , Shuah Khan , Randy Dunlap , Andrew Morton , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , linux-arm-kernel@lists.infradead.org, linux-trace-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, linux-doc@vger.kernel.org, llvm@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [RFC PATCH v2 13/13] locking/selftest: Exercise hardirq return-tail preparation Date: Wed, 28 Oct 2026 04:31:27 +0100 Message-Id: <20261028033127.82193-14-kmehltretter@gmail.com> X-Mailer: git-send-email 2.39.5 (Apple Git-154) In-Reply-To: <20261028033127.82193-1-kmehltretter@gmail.com> References: <20261028033127.82193-1-kmehltretter@gmail.com> X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The return-tail lockdep preparation must see a live hardirq context. A zero depth must fail. Depth one and nested contexts must pass. The ordinary preparation helper must continue to reject a live hardirq context. Add focused boot-time lockdep cases for those four states. Skip the final IRQ-state transition after an expected preparation failure so that each failure remains attributable to the preparation invariant. Assisted-by: LLM --- lib/locking-selftest.c | 53 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 53 insertions(+) diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c index c3d976c801bb4..7e26b757344a4 100644 --- a/lib/locking-selftest.c +++ b/lib/locking-selftest.c @@ -222,6 +222,55 @@ static void init_shared_classes(void) local_irq_enable(); \ local_bh_enable(); +static void irqtail_prepare_test_enter(unsigned int nr) +{ + unsigned int i; + + local_irq_disable(); + for (i = 0; i < nr; i++) + __irq_enter_raw(); + trace_hardirqs_on_prepare(); +} + +static void irqtail_prepare_test_exit(unsigned int nr) +{ + unsigned int i; + + for (i = 0; i < nr; i++) + __irq_exit_raw(); + if (debug_locks) + lockdep_hardirqs_on(_THIS_IP_); + raw_local_irq_enable(); +} + +static void prepare_irqtail_0(void) +{ + irqtail_prepare_test_enter(0); + lockdep_hardirqs_on_prepare_irqtail(); + irqtail_prepare_test_exit(0); +} + +static void prepare_irqtail_1(void) +{ + irqtail_prepare_test_enter(1); + lockdep_hardirqs_on_prepare_irqtail(); + irqtail_prepare_test_exit(1); +} + +static void prepare_irqtail_2(void) +{ + irqtail_prepare_test_enter(2); + lockdep_hardirqs_on_prepare_irqtail(); + irqtail_prepare_test_exit(2); +} + +static void prepare_regular_1(void) +{ + irqtail_prepare_test_enter(1); + lockdep_hardirqs_on_prepare(); + irqtail_prepare_test_exit(1); +} + /* * Shortcuts for lock/unlock API variants, to keep * the testcases compact: @@ -2934,6 +2983,10 @@ void locking_selftest(void) DO_TESTCASE_6x2x2RW("irq read-recursion", irq_read_recursion); DO_TESTCASE_6x2x2RW("irq read-recursion #2", irq_read_recursion2); DO_TESTCASE_6x2x2RW("irq read-recursion #3", irq_read_recursion3); + DO_TESTCASE_1B("IRQ tail prepare", prepare_irqtail, 0); + DO_TESTCASE_1("IRQ tail prepare", prepare_irqtail, 1); + DO_TESTCASE_1("IRQ tail prepare", prepare_irqtail, 2); + DO_TESTCASE_1B("regular IRQ prepare", prepare_regular, 1); ww_tests(); -- 2.39.5 (Apple Git-154)