[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] Questions on EPT dump and creation

First,ÂI used "xm debug-key D" to dump ept mappings. But I have a doubt about the mapping.
I started a 32bit HVM which memory is 512, so the max gfn should be 0x1ffff. But the result of "xm dmesg" showed gfn->mfn mapping until 0xfffff.
Output looked like below:
(XEN) gfn: fc012 Âmfn: 179e6
(XEN) gfn: fc013 Âmfn: 179e5
(XEN) gfn: fee00 Âmfn: 2e8
(XEN) gfn: feffb Âmfn: 178fd
(XEN) gfn: feffc Âmfn: 178fc
(XEN) gfn: feffd Âmfn: 178fb
(XEN) gfn: feffe Âmfn: 178fa
(XEN) gfn: fefff Âmfn: 178f9
(XEN) gfn: fffff Âmfn: 2eb

What I think is every HVM has one EPT table and the table maps the allocated memory like from 0 to 0x1ffff, why does the HVM ept map all the 4G space?
Isn't it unneccessary and waste of memory?

Second, I want to copy the system ept and used the copy for later translation.ÂSince the HVM is 512M, so I need one PML4 pointed by eptp, one PDP pointed by PML4 entry[0], one PD pointed by PDP entry[0], 512 PT's pointed by all PD entries. After all settings are done, I'v got gfn->mfn mapping of 1G memory. I think it should be working, but not. Where am I wrong?ÂWhat would I pay attention to?

Looking forward to your help,

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.