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From: Mulyadi Santosa <mulyadi.santosa@gmail.com>
Date: Wed, 15 Dec 2010 15:31:53 +0700
Message-ID: <AANLkTikFBij8fDM5bFo4UCz-mjgeLWkcbdfP389yWrBw@mail.gmail.com>
Subject: Re: [Qemu-devel] Sometimes qem-kvm hang at kvm_put_vcpu_events when
	virsh restore. Both version 0.12.5 / 0.13.0
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To: changlimin <changlimin@h3c.com>
Cc: qemu-devel@nongnu.org

On Wed, Dec 15, 2010 at 15:08, changlimin <changlimin@h3c.com> wrote:
> 1. I create a guest use libvirt;
> 2. I start the guest use: virsh start guest;
> 3. I save the guest to a file, use: virsh save guest guest.save
> 4. I retore the guest, use : virsh retore guest.save
> =A0 =A0Sometimes, the guest restore successful. sometimes restore fail.
> =A0 =A0I debug the code, the qemu-kvm hang at =A0kvm_put_vcpu_events, the=
 process state is D, uninterruptable sleep. Only can killed by kill -9.
> =A0 =A0I print the events when kvm_put_vcpu_events / kvm_get_vcpu_events,=
 it is always different, event when restore successful

I could only say, i smell deadlock due to race condition here...but I
have no further prove...how many (virtual) CPU did you simulate at
that time?

--=20
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com