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Date: Mon, 6 Jan 2025 10:51:38 +0100
From: Greg KH <gregkh@linuxfoundation.org>
To: wujing <realwujing@qq.com>
Cc: sasha.levin@linux.microsoft.com, mingo@redhat.com, peterz@infradead.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	wujing <realwujing@gmail.com>,
	QiLiang Yuan <yuanql9@chinatelecom.cn>
Subject: Re: [PATCH] sched/fair: Correct CPU selection from isolated domain
Message-ID: <2025010654-underpay-habitant-fb9e@gregkh>
References: <tencent_160A5B6C838FD9A915A67E67914350EB1806@qq.com>
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On Mon, Jan 06, 2025 at 05:26:34PM +0800, wujing wrote:
> From: wujing <realwujing@gmail.com>
> 
> We encountered an issue where the kernel thread `ksmd` runs on the PMD
> dedicated isolated core, leading to high latency in OVS packets.
> 
> Upon analysis, we discovered that this is caused by the current
> select_idle_smt() function not taking the sched_domain mask into account.
> 
> Kernel version: linux-4.19.y

You do know that 4.19.y is long end-of-life and totally insecure and
nothing that you should be using in anything, right?  Please move to a
more modern kernel version.

good luck!

greg k-h