From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 A93852874ED for ; Sat, 28 Mar 2026 01:42:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774662151; cv=none; b=He+iKrBCV8ZECCHlMgYhZlzZaA7hrWhxCqNvCAO8AsIy2Aj08Axk+MLMhizn4heFEYfr0Dmbkmsm1Vc5cEO4jWKtbTdkNu3uaL/qWyXDK1VT63cc+v56o383AO300MGBozUiXgYOQIhDl2/7NOUQoIOmUOiwRsmxjFCoNdR+8Ks= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774662151; c=relaxed/simple; bh=Zxw6BEZt/X5JWZF3CLG8PgkbvRurpxDy3dPdY2ecr2A=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=q54BZuupxT546d7fisoVoUyw8/utvQOT6VKOC9ymJHr/0/zsrHr+kqpGTOWOo6IQ21kA0JL+uT8oOPsDtw13taFXHFBDUWOwyxin3Jo/NZdJuwho71fGMUFBogHtMz/iPpWhOa5F67vBmsJFiB+6kJu8w08luAr89nqeqN6u0rQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=JFX7/IYj; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="JFX7/IYj" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1774662148; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CqVzxyiLsd5PaN4PD+PqCSkisCpB3wCYllL7dq7ATMc=; b=JFX7/IYjVbshtkklXzGcaEPbKJd/wi3G2SoZ9fARgbOK1SQqg527ZglRNbrZebVpwxI0O4 fiMUgX7IpdHOVS+GbwXocAZul5l9Y3TcpCst4Q6Y037FcxokwdekAsVt13f3tzY/zr8ziX aZVI2MfG5HaZodWTdjyjPKwH0es6TPE= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-639-beep6VKfNx6E7MCVPWMNaw-1; Fri, 27 Mar 2026 21:42:26 -0400 X-MC-Unique: beep6VKfNx6E7MCVPWMNaw-1 X-Mimecast-MFC-AGG-ID: beep6VKfNx6E7MCVPWMNaw_1774662145 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4D391195608C; Sat, 28 Mar 2026 01:42:25 +0000 (UTC) Received: from [10.22.90.2] (unknown [10.22.90.2]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id DA4721955D71; Sat, 28 Mar 2026 01:42:23 +0000 (UTC) Message-ID: <746bf9c6-c35c-4c2d-b874-46cdc34d2cc4@redhat.com> Date: Fri, 27 Mar 2026 21:42:23 -0400 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] cgroup/cpuset: Skip security check for hotplug induced v1 task migration To: Tejun Heo Cc: Chen Ridong , Johannes Weiner , =?UTF-8?Q?Michal_Koutn=C3=BD?= , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260327201546.2463644-1-longman@redhat.com> Content-Language: en-US From: Waiman Long In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 On 3/27/26 4:22 PM, Tejun Heo wrote: > On Fri, Mar 27, 2026 at 04:15:46PM -0400, Waiman Long wrote: >> + /* >> + * Set to true if a kthread is moving tasks away from a v1 cpuset with >> + * no CPUs >> + */ >> + kthread_move_task_from_empty_cs = !cpuset_v2() && >> + cpumask_empty(oldcs->effective_cpus) && >> + (current->flags & PF_KTHREAD); > PF_KTHREAD test seems odd. Can't you pass this in as a flag from hotplug > handler? Yes, I can added a new CS flag like CS_TASK_MIGRATION in the hotplug handler to indicate that task migration is allowed. Thanks for the suggestion. I will send a v2 with that change. Cheers, Longman