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Date:   Sat, 10 Sep 2022 11:11:43 -0700
From:   Isaku Yamahata <isaku.yamahata@gmail.com>
To:     Chao Gao <chao.gao@intel.com>
Cc:     isaku.yamahata@intel.com, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
        Yuan Yao <yuan.yao@linux.intel.com>, isaku.yamahata@gmail.com,
        Kai Huang <kai.huang@intel.com>,
        Atish Patra <atishp@atishpatra.org>,
        Shaokun Zhang <zhangshaokun@hisilicon.com>,
        Qi Liu <liuqi115@huawei.com>,
        John Garry <john.garry@huawei.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Huang Ying <ying.huang@intel.com>,
        Huacai Chen <chenhuacai@kernel.org>
Subject: Re: [PATCH v4 10/26] KVM: Drop kvm_count_lock and instead protect
 kvm_usage_count with kvm_lock
Message-ID: <20220910181143.GC699006@ls.amr.corp.intel.com>
References: <cover.1662679124.git.isaku.yamahata@intel.com>
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On Fri, Sep 09, 2022 at 11:05:34AM +0800,
Chao Gao <chao.gao@intel.com> wrote:

> >+	 * cpu_hotplug_disable() and other CPUs are offlined.  No need for
> >+	 * locking.
> >+	 */
> >+	lockdep_assert_not_held(&kvm_lock);
> >+
> >+	if (kvm_usage_count) {
> >+		preempt_disable();
> > 		hardware_disable_nolock(NULL);
> >+		preempt_enable();
> 
> kvm_suspend() is called with interrupt disabled. So, no need to disable
> preemption.
> 
> /**
>  * syscore_suspend - Execute all the registered system core suspend callbacks.
>  *
>  * This function is executed with one CPU on-line and disabled interrupts.
>  */
> int syscore_suspend(void)

Thanks, I'll fix it with a comment.
-- 
Isaku Yamahata <isaku.yamahata@gmail.com>