From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 D1FF83B42F3 for ; Mon, 8 Jun 2026 08:36:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780907817; cv=none; b=Qy3va5RPvcMUCtGzRq/Lc+N2S28+f1WpU5mHPJuyBWMEuX8gHaFaqAJ63djBq4H2ett/L2GrFY4DHWNyTy2YU0zGOrIPZ8EfDq8u5gzxYFKHK1wUi41+yjKL9jzwV+HiDbV9bPbIRIXqpTn+GpFGLFPZAAyhol425YZCNO6u3mQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780907817; c=relaxed/simple; bh=OHY6SnQCvTDrOgIK7zRo0G6rC7upGz57TvNtEGfF8pA=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Il2ChHXt+nKOG3c/jmY9mtAUzo6WIFE+eRmAtqEACoKWhf/0QLTa2BKdTxc7+GBKnXEWqNzE5nm9ttgfIyZoweUT2jTzo1zfxjFjA1MHdRdy+HfOrzCu+aaneNQhVnNcYrcAdOfalYgw9rJbk0JGAo22uixkkP2QdLw278/ew74= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mtW0htLT; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mtW0htLT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55AAD1F00893; Mon, 8 Jun 2026 08:36:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780907812; bh=OHY6SnQCvTDrOgIK7zRo0G6rC7upGz57TvNtEGfF8pA=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=mtW0htLTO4fd27ThbV/8h6lFZOTO7Kyklg3tDCd6IpE1iGPzOdewgoXyST9C6f8lb 6uQ9Hb+vrCvpRUCsIA8B5/Ya1WuS+yphDwfH2O1c4dDsug3qAJrivpjz19hJSXE05x AFjOXAaBIiIdyQo/U9PakeQ83C7/J6wVEAOn7m8mmbQEnKficu00d69MpbTCYiF752 vlVvcqY7zY3RMuvMyhlhXOKscVP32OwISsqvjMttD1Q8vDDTfeLTjDYOVFeahXOx42 ihmzsRq3uVFEJOC4KPF4TMsoA+DR+Qv/9YX0T3JldboTO/6pKk3CZXs7bwtQWo5ubF 1PzQDkIDTBXNw== From: Thomas Gleixner To: Chen Yu , tony.luck@intel.com, reinette.chatre@intel.com Cc: x86@kernel.org, linux-kernel@vger.kernel.org, bp@alien8.de, mingo@redhat.com, dave.hansen@linux.intel.com, hpa@zytor.com, dave.martin@arm.com, james.morse@arm.com, fenghuay@nvidia.com, babu.moger@amd.com, anil.keshavamurthy@broadcom.com Subject: Re: [PATCH v3 5/6] fs/resctrl: Do not invoke smp_processor_id() in preemptible context In-Reply-To: References: Date: Mon, 08 Jun 2026 10:36:48 +0200 Message-ID: <87v7bt4ee7.ffs@fw13> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Sat, Jun 06 2026 at 10:38, Chen Yu wrote: > From: Tony Luck > > __l3_mon_event_count() and __l3_mon_event_count_sum() call > smp_processor_id() to obtain the current CPU. However, some > monitor events can be read from any CPU in task context via > mon_event_count(); in that case the calling context is > preemptible and smp_processor_id() triggers a debug warning. Is this new with this MMIO stuff or is this an existing issue? If the latter then this patch should be in front of the series and get a fixes tag. If not the change log should explain it.