linux-kernel - Re: [cgroup/for-6.19 PATCH 2/3] cgroup/cpuset: Fail if isolated and nohz

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <05281aa9-57c4-42c7-a17c-009d6b22943b@huaweicloud.com>
Date: Mon, 3 Nov 2025 11:53:38 +0800
From: Chen Ridong <chenridong@...weicloud.com>
To: Waiman Long <longman@...hat.com>, Tejun Heo <tj@...nel.org>,
 Johannes Weiner <hannes@...xchg.org>, Michal Koutný
 <mkoutny@...e.com>
Cc: cgroups@...r.kernel.org, linux-kernel@...r.kernel.org,
 Chen Ridong <chenridong@...wei.com>, Gabriele Monaco <gmonaco@...hat.com>,
 Frederic Weisbecker <frederic@...nel.org>
Subject: Re: [cgroup/for-6.19 PATCH 2/3] cgroup/cpuset: Fail if isolated and
 nohz_full don't leave any housekeeping




> +
>  	/*
>  	 * Change the parent's effective_cpus & effective_xcpus (top cpuset
>  	 * only).
> @@ -2994,7 +3055,11 @@ static int update_prstate(struct cpuset *cs, int new_prs)
>  		 * A change in load balance state only, no change in cpumasks.
>  		 * Need to update isolated_cpus.
>  		 */
> -		isolcpus_updated = true;
> +		if ((new_prs == PRS_ISOLATED) &&
> +		    !isolated_cpus_can_update(cs->effective_xcpus, NULL))
> +			err = PERR_HKEEPING;
> +		else
> +			isolcpus_updated = true;
>  	} else {
>  		/*
>  		 * Switching back to member is always allowed even if it

This is an issue I am trying to fix, the prstate_housekeeping_conflict check is necessary.

https://lore.kernel.org/cgroups/20251025064844.495525-2-chenridong@huaweicloud.com/

-- 
Best regards,
Ridong