From: Avi Kivity <avi@redhat.com>
To: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Andrea Arcangeli <aarcange@redhat.com>,
t.hirofuchi@aist.go.jp, qemu-devel@nongnu.org,
kvm@vger.kernel.org, satoshi.itoh@aist.go.jp
Subject: Re: [Qemu-devel] [PATCH 0/2][RFC] postcopy migration: Linux char device for postcopy
Date: Thu, 29 Dec 2011 15:52:58 +0200 [thread overview]
Message-ID: <4EFC70BA.1080808@redhat.com> (raw)
In-Reply-To: <20111229134920.GH19274@valinux.co.jp>
On 12/29/2011 03:49 PM, Isaku Yamahata wrote:
> >
> > qemu can have an extra thread that wait4()s the daemon, and relaunch
> > it. This extra thread would not be blocked by the page fault. It can
> > keep the fd so it isn't lost.
> >
> > The unkillability of process A is a security issue; it could be done on
> > purpose. Is it possible to change umem to sleep with
> > TASK_INTERRUPTIBLE, so it can be killed?
>
> The issue is how to solve the page fault, not whether TASK_INTERRUPTIBLE or
> TASK_UNINTERRUPTIBLE.
> I can think of several options.
> - When daemon X is dead, all page faults are served by zero pages.
> - When daemon X is dead, all page faults are resovled as VM_FAULT_SIGBUS
> - list/reattach: complications. You don't like it
> - other?
Don't resolve the page fault. It's up to the user/system to make sure
it happens. qemu can easily do it by watching for the daemon's death
and respawning it.
When the new daemon is started, it can ask the kernel for a list of
pending requests, and service them.
--
error compiling committee.c: too many arguments to function
next prev parent reply other threads:[~2011-12-29 13:53 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-12-29 1:26 [Qemu-devel] [PATCH 0/2][RFC] postcopy migration: Linux char device for postcopy Isaku Yamahata
2011-12-29 1:26 ` [Qemu-devel] [PATCH 1/2] export necessary symbols Isaku Yamahata
2011-12-29 1:26 ` [Qemu-devel] [PATCH 2/2] umem: chardevice for kvm postcopy Isaku Yamahata
2011-12-29 11:17 ` Avi Kivity
2011-12-29 12:22 ` Isaku Yamahata
2011-12-29 12:47 ` Avi Kivity
2012-01-05 4:08 ` [Qemu-devel] 回复: " thfbjyddx
2012-01-05 10:48 ` [Qemu-devel] 回??: " Isaku Yamahata
2012-01-05 11:10 ` Tommy
2012-01-05 12:18 ` Isaku Yamahata
2012-01-05 15:02 ` Tommy Tang
[not found] ` <4F05BB68.9050302@hotmail.com>
2012-01-05 15:05 ` Tommy Tang
2012-01-06 7:02 ` thfbjyddx
2012-01-06 17:13 ` [Qemu-devel] 回??: [PATCH 2/2] umem: chardevice for kvm?postcopy Isaku Yamahata
2011-12-29 1:31 ` [Qemu-devel] [PATCH 0/2][RFC] postcopy migration: Linux char device for postcopy Isaku Yamahata
2011-12-29 11:24 ` Avi Kivity
2011-12-29 12:39 ` Isaku Yamahata
2011-12-29 12:55 ` Avi Kivity
2011-12-29 13:49 ` Isaku Yamahata
2011-12-29 13:52 ` Avi Kivity [this message]
2011-12-29 14:18 ` Isaku Yamahata
2011-12-29 14:35 ` Avi Kivity
2011-12-29 14:49 ` Isaku Yamahata
2011-12-29 14:55 ` Avi Kivity
2011-12-29 15:53 ` Isaku Yamahata
2011-12-29 16:00 ` Avi Kivity
2011-12-29 16:01 ` Avi Kivity
2012-01-02 17:05 ` Andrea Arcangeli
2012-01-02 17:55 ` Paolo Bonzini
2012-01-03 14:25 ` Andrea Arcangeli
2012-01-12 13:57 ` Avi Kivity
2012-01-13 2:06 ` Andrea Arcangeli
2012-01-04 3:03 ` Isaku Yamahata
2012-01-12 13:59 ` Avi Kivity
2012-01-13 1:09 ` Benoit Hudzia
2012-01-13 1:31 ` Takuya Yoshikawa
2012-01-13 9:40 ` Benoit Hudzia
2012-01-13 2:03 ` Isaku Yamahata
2012-01-13 2:15 ` Isaku Yamahata
2012-01-13 9:55 ` Benoit Hudzia
2012-01-13 9:48 ` Benoit Hudzia
2012-01-13 2:09 ` Andrea Arcangeli
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