From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AE7D1190664; Wed, 21 Jan 2026 01:07:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768957671; cv=none; b=HxBZhMstDGcpyvfFrE8WhCkEPP3Bh6flceslrmiwdHAdLkN6BCGBvWrV3Ypo9vxVLRnSl16XtvYmaXEY2+WjRBXH1+XeXllAqOGzo9FaOx2EauD4mQrBdEATWNHdbAd61BenPc+xa/9uQNuZm6oz9Gx4FPknf1JZ8AI9NTELf/k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768957671; c=relaxed/simple; bh=5idTwFNzS2Q+TB3Lx9INhPxb7Ar05bCuaPgK9mFvHNA=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=SepckVuR3UZUhXbdkDv81TiRqWvj5BYYlZsKcJ+y/9DTjCrdoxpFmOf7yNMkHDFT5hAohJhcw8gCXGKHtQyMH+wPKhkSRjGAHNfzKx+F3nPUxvwz7SoBqiuaeGTQ/Sep7e8ANJSJlxayeVpgF73yBfYPmckbXKx4Rsf1aMKw8Dg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cOExnnPj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cOExnnPj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A08CC16AAE; Wed, 21 Jan 2026 01:07:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768957671; bh=5idTwFNzS2Q+TB3Lx9INhPxb7Ar05bCuaPgK9mFvHNA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=cOExnnPjHgBezBYF7WZeggvUHHXa4XOrJ7ckHvyrXVllE7dDFo12IF8t12F2A/Zoh TUn53mTb2MiZES9kxEtAs6UuQzYMRliNeEKPDXEQQ7hpOwIIBlb8joIO5VdLPBUeKS F9DwWY/AJUjoAdrFTIuzTQ4tbp7jganB2OqG2e2ejCLmplbAy72cCCB8Yt9pArX0CP aPeZK/kkzNqiiftSJiCR+63IHNO2/Y990jdq6Ug29CahtrRUm9W1n2xeXX3Ake6PG2 jRdKHYTX3Q35drWhhe5UZsB8Yt+ZsWDgwY38XU7CLgpqaPQpFwdqNcxnwlvuMuSd0n oDh3Y/8DXjoSg== Date: Wed, 21 Jan 2026 10:07:46 +0900 From: Masami Hiramatsu (Google) To: kernel test robot Cc: , , Steven Rostedt , , , Naveen N Rao , "David S . Miller" Subject: Re: [PATCH v2] kprobes: Use dedicated kthread for kprobe optimizer Message-Id: <20260121100746.e8c7d0da85f8b68620489c5e@kernel.org> In-Reply-To: <202601191507.74fccd0c-lkp@intel.com> References: <176826884613.429923.16578111751623731056.stgit@devnote2> <202601191507.74fccd0c-lkp@intel.com> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 19 Jan 2026 15:29:58 +0800 kernel test robot wrote: > > > Hello, > > kernel test robot noticed "INFO:task_blocked_for_more_than#seconds" on: OOps, yes. It should be wait in interruptible. Thanks, > > commit: 62f65c2531ad66e84c1a5ef91389322357ef6db4 ("[PATCH v2] kprobes: Use dedicated kthread for kprobe optimizer") > url: https://github.com/intel-lab-lkp/linux/commits/Masami-Hiramatsu-Google/kprobes-Use-dedicated-kthread-for-kprobe-optimizer/20260113-094928 > base: https://git.kernel.org/cgit/linux/kernel/git/trace/linux-trace for-next > patch link: https://lore.kernel.org/all/176826884613.429923.16578111751623731056.stgit@devnote2/ > patch subject: [PATCH v2] kprobes: Use dedicated kthread for kprobe optimizer > > in testcase: trinity > version: trinity-x86_64-294c4652-1_20251011 > with following parameters: > > runtime: 300s > group: group-03 > nr_groups: 5 > > > > config: x86_64-kexec > compiler: clang-20 > test machine: qemu-system-x86_64 -enable-kvm -cpu SandyBridge -smp 2 -m 32G > > (please refer to attached dmesg/kmsg for entire log/backtrace) > > > +-----------------------------------------+------------+------------+ > | | 78a419b44e | 62f65c2531 | > +-----------------------------------------+------------+------------+ > | INFO:task_blocked_for_more_than#seconds | 0 | 6 | > +-----------------------------------------+------------+------------+ > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > the same patch/commit), kindly add following tags > | Reported-by: kernel test robot > | Closes: https://lore.kernel.org/oe-lkp/202601191507.74fccd0c-lkp@intel.com > > > > [ 972.359932][ T32] INFO: task kprobe-optimize:18 blocked for more than 491 seconds. > [ 972.361221][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 972.362516][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 972.364322][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 972.366628][ T32] Call Trace: > [ 972.367378][ T32] > [ 972.368066][ T32] __schedule (kernel/sched/core.c:5259) > [ 972.370837][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 972.371679][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 972.373219][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 972.374017][ T32] kthread (kernel/kthread.c:465) > [ 972.374573][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 972.375364][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 972.376005][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 972.376679][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 972.377305][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 972.377958][ T32] > [ 1463.879952][ T32] INFO: task kprobe-optimize:18 blocked for more than 983 seconds. > [ 1463.882239][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 1463.884371][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 1463.887443][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 1463.891867][ T32] Call Trace: > [ 1463.893396][ T32] > [ 1463.894468][ T32] __schedule (kernel/sched/core.c:5259) > [ 1463.903984][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 1463.904926][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 1463.905949][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 1463.907111][ T32] kthread (kernel/kthread.c:465) > [ 1463.907954][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 1463.909157][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 1463.910045][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 1463.910939][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 1463.911933][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 1463.912947][ T32] > [ 1955.399991][ T32] INFO: task kprobe-optimize:18 blocked for more than 1474 seconds. > [ 1955.404266][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 1955.407452][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 1955.414557][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 1955.416961][ T32] Call Trace: > [ 1955.417705][ T32] > [ 1955.418382][ T32] __schedule (kernel/sched/core.c:5259) > [ 1955.419274][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 1955.419929][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 1955.421071][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 1955.422303][ T32] kthread (kernel/kthread.c:465) > [ 1955.423217][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 1955.424452][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 1955.425189][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 1955.425913][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 1955.426645][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 1955.427357][ T32] > [ 2446.919964][ T32] INFO: task kprobe-optimize:18 blocked for more than 1966 seconds. > [ 2446.922105][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 2446.925697][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 2446.926569][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 2446.927775][ T32] Call Trace: > [ 2446.928242][ T32] > [ 2446.928609][ T32] __schedule (kernel/sched/core.c:5259) > [ 2446.929827][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 2446.930256][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 2446.930789][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 2446.931434][ T32] kthread (kernel/kthread.c:465) > [ 2446.931926][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 2446.932624][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 2446.933079][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 2446.933534][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 2446.933983][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 2446.934450][ T32] > [ 2938.439916][ T32] INFO: task kprobe-optimize:18 blocked for more than 2457 seconds. > [ 2938.441278][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 2938.442281][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 2938.444599][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 2938.446316][ T32] Call Trace: > [ 2938.446892][ T32] > [ 2938.447449][ T32] __schedule (kernel/sched/core.c:5259) > [ 2938.449286][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 2938.450230][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 2938.451347][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 2938.452611][ T32] kthread (kernel/kthread.c:465) > [ 2938.453462][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 2938.454622][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 2938.455583][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 2938.456604][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 2938.457614][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 2938.458645][ T32] > [ 3429.960057][ T32] INFO: task kprobe-optimize:18 blocked for more than 2949 seconds. > [ 3429.962853][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 3429.965133][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 3429.967986][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 3429.971731][ T32] Call Trace: > [ 3429.973021][ T32] > [ 3429.974169][ T32] __schedule (kernel/sched/core.c:5259) > [ 3429.975713][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 3429.977206][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 3429.978375][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 3429.979623][ T32] kthread (kernel/kthread.c:465) > [ 3429.980602][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 3429.981810][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 3429.982797][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 3429.983793][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 3429.984838][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 3429.985864][ T32] > [ 3921.480064][ T32] INFO: task kprobe-optimize:18 blocked for more than 3440 seconds. > [ 3921.482942][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 3921.485260][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 3921.488269][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 3921.491811][ T32] Call Trace: > [ 3921.493488][ T32] > [ 3921.494960][ T32] __schedule (kernel/sched/core.c:5259) > [ 3921.508616][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 3921.509430][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 3921.510413][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 3921.511467][ T32] kthread (kernel/kthread.c:465) > [ 3921.512331][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 3921.513388][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 3921.514202][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 3921.514976][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 3921.515773][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 3921.516817][ T32] > [ 4413.000017][ T32] INFO: task kprobe-optimize:18 blocked for more than 3932 seconds. > [ 4413.004653][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 4413.007745][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 4413.010446][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 4413.013906][ T32] Call Trace: > [ 4413.015027][ T32] > [ 4413.016134][ T32] __schedule (kernel/sched/core.c:5259) > [ 4413.017465][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 4413.018294][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 4413.019366][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 4413.020594][ T32] kthread (kernel/kthread.c:465) > [ 4413.021350][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 4413.022331][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 4413.023124][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 4413.023925][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 4413.025015][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 4413.026074][ T32] > [ 4904.520028][ T32] INFO: task kprobe-optimize:18 blocked for more than 4423 seconds. > [ 4904.521949][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 4904.528612][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 4904.529924][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 4904.531461][ T32] Call Trace: > [ 4904.531896][ T32] > [ 4904.532406][ T32] __schedule (kernel/sched/core.c:5259) > [ 4904.532947][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 4904.533381][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 4904.533944][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 4904.534547][ T32] kthread (kernel/kthread.c:465) > [ 4904.534985][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 4904.535670][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 4904.536359][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 4904.536831][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 4904.537310][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 4904.537788][ T32] > [ 5396.039936][ T32] INFO: task kprobe-optimize:18 blocked for more than 4915 seconds. > [ 5396.040939][ T32] Not tainted 6.19.0-rc5-00040-g62f65c2531ad #1 > [ 5396.041631][ T32] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. > [ 5396.042742][ T32] task:kprobe-optimize state:D stack:0 pid:18 tgid:18 ppid:2 task_flags:0x208040 flags:0x00080000 > [ 5396.045182][ T32] Call Trace: > [ 5396.045723][ T32] > [ 5396.046266][ T32] __schedule (kernel/sched/core.c:5259) > [ 5396.046928][ T32] schedule (arch/x86/include/asm/preempt.h:85 kernel/sched/core.c:6946 kernel/sched/core.c:6960) > [ 5396.047542][ T32] kprobe_optimizer_thread (kernel/kprobes.c:656) > [ 5396.048329][ T32] ? __pfx_autoremove_wake_function (kernel/sched/wait.c:402) > [ 5396.049182][ T32] kthread (kernel/kthread.c:465) > [ 5396.049803][ T32] ? __pfx_kprobe_optimizer_thread (kernel/kprobes.c:654) > [ 5396.050654][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 5396.051353][ T32] ret_from_fork (arch/x86/kernel/process.c:164) > [ 5396.052048][ T32] ? __pfx_kthread (kernel/kthread.c:412) > [ 5396.052723][ T32] ret_from_fork_asm (arch/x86/entry/entry_64.S:256) > [ 5396.053187][ T32] > [ 5396.053524][ T32] Future hung task reports are suppressed, see sysctl kernel.hung_task_warnings > BUG: kernel hang in test stage > > > > The kernel config and materials to reproduce are available at: > https://download.01.org/0day-ci/archive/20260119/202601191507.74fccd0c-lkp@intel.com > > > > -- > 0-DAY CI Kernel Test Service > https://github.com/intel/lkp-tests/wiki > -- Masami Hiramatsu (Google)