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Message-ID: <0022a85f16c1f1dc14decdc71f58af492b45b50d.camel@linux.intel.com>
Subject: Re: [PATCH v3 2/3] KVM: keep track of running ioctls
From:   Robert Hoo <robert.hu@linux.intel.com>
To:     Emanuele Giuseppe Esposito <eesposit@redhat.com>,
        qemu-devel@nongnu.org
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Richard Henderson <richard.henderson@linaro.org>,
        Eduardo Habkost <eduardo@habkost.net>,
        Marcel Apfelbaum <marcel.apfelbaum@gmail.com>,
        Philippe =?ISO-8859-1?Q?Mathieu-Daud=E9?= <philmd@linaro.org>,
        Yanan Wang <wangyanan55@huawei.com>, kvm@vger.kernel.org,
        David Hildenbrand <david@redhat.com>
Date:   Fri, 02 Dec 2022 21:32:01 +0800
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On Fri, 2022-12-02 at 13:03 +0100, Emanuele Giuseppe Esposito wrote:
...
> > > @@ -3032,7 +3035,9 @@ int kvm_vcpu_ioctl(CPUState *cpu, int type,
> > > ...)
> > >      va_end(ap);
> > >  
> > >      trace_kvm_vcpu_ioctl(cpu->cpu_index, type, arg);
> > > +    accel_cpu_ioctl_begin(cpu);
> > 
> > Does this mean that kvm_region_commit() can inhibit any other vcpus
> > doing any ioctls?
> 
> Yes, because we must prevent any vcpu from reading memslots while we
> are
> updating them.
> 
But do most other vm/vcpu ioctls contend with memslot operations?