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Subject: Re: [PATCH] KVM: X86: Fix exception untrigger on ret to user
To:     Jim Mattson <jmattson@google.com>
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
        kvm@vger.kernel.org
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29.06.2021 01:35, Jim Mattson пишет:
> How long are you willing to defer the EINTR? What if you're running at
> the target of a live migration, and the guest's IDT page needs to be
> demand-fetched over the network? It may be quite some time before you
> can actually deliver that exception.

OK, understood, thank you.
I wonder how many other non-atomic
things are there in KVM, but probably
that doesn't matter much, if
run->ready_for_injection covers them
all at once...