From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout05.his.huawei.com (canpmsgout05.his.huawei.com [113.46.200.220]) (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 E07353749F4; Tue, 16 Jun 2026 13:12:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.220 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781615577; cv=none; b=Hvwi8gnW8J7ZriM8KpndguTj68rI27L4+f3tP5o15titW05Q+HJE6dqK0EEGtZW61ld0SpzY4qbhD+PKTppq+EDG4qvOHIRtXsAqMP3P5LVcMD5XbqALNhxZtPGBmN7VbdLna0hOpCQiYqmrPCNYOLj2q7gwp8x0QpLBygJq4Iw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781615577; c=relaxed/simple; bh=2YMS1TPdKj8YZTAzLmxweixUsQJT5reuFUutt0QorUs=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=TFjki6QJrykaBY4G6hIVZGPGQZgINn4PPAkFSSHKAgDjPmnSFswCcQERHE97pN4yZBWDX7ipCdu/u5d7i4v3Cg/V3fnYpKAoDCD/qVWYjb3nxL18S0MVc80rW1CY0kYuH78C6VsWGBgTmQWGXTVR4m82xpHcM1W1n5WUZsMl920= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=h-partners.com; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b=os/ptCz2; arc=none smtp.client-ip=113.46.200.220 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=h-partners.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b="os/ptCz2" dkim-signature: v=1; a=rsa-sha256; d=h-partners.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=9E0DuBf96JZkkmK5Hg++NskVSILbsCcyEZOXqhBthHU=; b=os/ptCz2VFlDM8YHnUy1o9aLibmW0ZIaOUjlp4LDeF21B0lCQck4WzMmPjMlGKODqmUqY7eQ/ wa0jx8iA8p7Z1K7eQioXtEEpGwyp23Pz3BIpmAohk5ibtG/Ky8abGIXMX4NCTT4ppx05VSEexwp btkXIa6Rccro3Dp3pmTlyKE= Received: from mail.maildlp.com (unknown [172.19.162.197]) by canpmsgout05.his.huawei.com (SkyGuard) with ESMTPS id 4gfnHg0bwwz12LF5; Tue, 16 Jun 2026 21:03:59 +0800 (CST) Received: from kwepemo100005.china.huawei.com (unknown [7.202.195.212]) by mail.maildlp.com (Postfix) with ESMTPS id 9441540569; Tue, 16 Jun 2026 21:12:50 +0800 (CST) Received: from [10.67.121.59] (10.67.121.59) by kwepemo100005.china.huawei.com (7.202.195.212) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Tue, 16 Jun 2026 21:12:49 +0800 Message-ID: Date: Tue, 16 Jun 2026 21:12:46 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH][v2] ACPI: processor_idle: Mark LPI enter functions as __cpuidle To: lirongqing , "Rafael J . Wysocki" , Len Brown , Sunil V L , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Sudeep Holla , , , References: <20260616072617.2272-1-lirongqing@baidu.com> From: "lihuisong (C)" In-Reply-To: <20260616072617.2272-1-lirongqing@baidu.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To kwepemo100005.china.huawei.com (7.202.195.212) On 6/16/2026 3:26 PM, lirongqing wrote: > From: Li RongQing > > When function tracing or Kprobes is enabled, entering an ACPI Low > Power Idle (LPI) state triggers the following RCU splat: > > RCU not on for: acpi_idle_lpi_enter+0x4/0xd8 > WARNING: CPU: 8 PID: 0 at include/linux/trace_recursion.h:162 function_trace_call+0x1e8/0x228 > > The acpi_idle_lpi_enter() function is invoked within the cpuidle > path after RCU has already been disabled for the current local CPU. > Consequently, ftrace's function_trace_call() expects RCU to be > actively watching before recording trace data, emitting a warning > if it is not. > > Fix this by annotating acpi_idle_lpi_enter(), the generic __weak > stub, and the RISC-V implementation of acpi_processor_ffh_lpi_enter() > with __cpuidle. This moves these functions into the '.cpuidle.text' > section, implicitly disabling ftrace instrumentation (notrace) along > this sensitive path and preventing trace-induced RCU warnings during > idle entry. > > Fixes: a36a7fecfe60 ("ACPI / processor_idle: Add support for Low Power Idle(LPI) states") > Signed-off-by: Li RongQing > --- LGTM, Acked-by: lihuisong@huawei.com