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From:   Thomas Gleixner <tglx@linutronix.de>
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To:     Marcelo Tosatti <mtosatti@redhat.com>, linux-kernel@vger.kernel.org
Cc:     Nitesh Lal <nilal@redhat.com>,
        Nicolas Saenz Julienne <nsaenzju@redhat.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Christoph Lameter <cl@linux.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Alex Belits <abelits@belits.com>, Peter Xu <peterx@redhat.com>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        Oscar Shiang <oscar0225@livemail.tw>,
        Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [patch v12 09/13] task isolation: add preempt notifier to sync
 per-CPU vmstat dirty info to thread info
In-Reply-To: <20220315153314.130167792@fedora.localdomain>
References: <20220315153132.717153751@fedora.localdomain>
 <20220315153314.130167792@fedora.localdomain>
Date:   Wed, 27 Apr 2022 09:11:41 +0200
Message-ID: <878rrryp8y.ffs@tglx>
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On Tue, Mar 15 2022 at 12:31, Marcelo Tosatti wrote:
> If a thread has task isolation activated, is preempted by thread B,
> which marks vmstat information dirty, and is preempted back in,
> one might return to userspace with vmstat dirty information on the 
> CPU in question.
>
> To address this problem, add a preempt notifier that transfers vmstat dirty
> information to TIF_TASK_ISOL thread flag.

How does this compile with CONFIG_KVM=n?

Thanks,

        tglx