Hi, the problem is as follows:(And then, others can't login mostly because of the os' busing and you can't do anything else.) [**@xentest ::三 12月 21::~]$ sudo xm list Name ID Mem VCPUs State Time(s) Domain-0 0 1748 2 r----- 29396.3 xp-101 1 256 1 -b---- 4685.8 [**@xentest ::三 12月 21::~]$ sudo xm save 1 1.save Message from syslogd@ at Wed Dec 21 10:27:10 2011 ... xentest kernel: unregister_netdevice: waiting for tap1.0 to become free. Usage count = 1 Message from syslogd@ at Wed Dec 21 10:27:41 2011 ... xentest last message repeated 3 times Message from syslogd@ at Wed Dec 21 10:28:52 2011 ... xentest last message repeated 7 times ....................... ------------------ 原始邮件 ------------------ 发件人: "Anthony PERARD"<anthony.per...@citrix.com>; 发送时间: 2011年12月20日(星期二) 晚上9:48 收件人: "Stefan Hajnoczi"<stefa...@gmail.com>; 抄送: "¤終於aware"<250716...@qq.com>; "qemu-devel"<qemu-devel@nongnu.org>; "Stefano Stabellini"<stefano.stabell...@eu.citrix.com>; "Xen Devel"<xen-de...@lists.xensource.com>; 主题: Re: 回复: [Qemu-devel] debuging about qemu-dm in xen 3.4.2
On Tue, 20 Dec 2011, Stefan Hajnoczi wrote: > 2011/12/20 ¤終於aware <250716...@qq.com>: > > I want to create a memory snapshot file (such as mm.snap) of current > > virtual machine and the mm.snap can be used as a arg of qemu cmd-line for > > restoring the last memory condition. > > But I am not very clear about the structure of the qemu-dm source code. > > Although observing the output of execution is the straightforward way, high > > frequency of printf and re-compling is too incovenient to put into effect. > > Please keep qemu-devel@nongnu.org CCed so others can contribute to the > discussion. > > QEMU only deals with virtual memory when simulating an MMU (for > ARM-on-x86 system translation). The device model usually operates on > physical RAM or bus addresses. > > Stefano or Anthony can explain the qemu-dm specifics. It's still not > clear to me what you're trying to observe - qemu-dm is not where I'd > try to observe domain memory under Xen but it's the right place to > observe emulated devices. Cced Xen-devel as well. You can save a domain state using the tool stack (probably `xm save` with Xen 3.4) and restore it as many time as you want. To run gdb on qemu-dm, remplace the /usr/lib/xen/bin/qemu-dm by a script: #!/bin/sh exec gdbserver 0.0.0.0:1234 /usr/lib/xen/bin/qemu-dm.bak $@ And run gdb. `target remote localhost 1234` to connect to gdbserver. With the latest Xen (4.1 and unstable), you can specifie a different device model in the config file instead of remplacing the default binary. Regards, -- Anthony PERARD