Message-ID: <75de91db-d3bc-0c0e-6199-ef00591e8878@redhat.com>
Date:   Thu, 2 Feb 2023 15:53:04 -0500
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Subject: Re: [PATCH 1/2] cpuset: Fix cpuset_cpus_allowed() to not filter
 offline CPUs
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To:     Tejun Heo <tj@kernel.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Will Deacon <will@kernel.org>, linux-kernel@vger.kernel.org,
        kernel-team@android.com, Zefan Li <lizefan.x@bytedance.com>,
        Johannes Weiner <hannes@cmpxchg.org>, cgroups@vger.kernel.org
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From:   Waiman Long <longman@redhat.com>
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On 2/2/23 15:48, Tejun Heo wrote:
> On Thu, Feb 02, 2023 at 03:46:02PM -0500, Waiman Long wrote:
>>>> I will work on a patchset to do that as a counter offer.
>>> We will need a small and simple patch for /urgent, or I will need to
>>> revert all your patches -- your call.
>>>
>>> I also don't tihnk you fully appreciate the ramifications of
>>> task_cpu_possible_mask(), cpuset currently gets that quite wrong.
>> OK, I don't realize the urgency of that. If it is that urgent, I will have
>> no objection to get it in for now. We can improve it later on. So are you
>> planning to get it into the current 6.2 rc or 6.3?
>>
>> Tejun, are you OK with that as you are the cgroup maintainer?
> Yeah, gotta fix the regression but is there currently a solution which fixes
> the regression but doesn't further break other stuff?

I believe there is a better way to do that, but it will need more time 
to flex out. Since cpuset_cpus_allowed() is only used by 
kernel/sched/core.c, Peter will be responsible if it somehow breaks 
other stuff.

Thanks,
Longman