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<DIV>Dear Eiraku san,</DIV>
<DIV> </DIV>
<DIV>Thank you very much. I can convert a gva to hpa now, and I can dump
the memory region of a process' or kernel's gva address. My source code is very
similar with the core/debug.c just added a function to read cr3~efer
registers.</DIV>
<DIV> </DIV>
<DIV dir=ltr align=left>void <BR>get_control_regs(ulong * cr0, ulong * cr3,
ulong * cr4, u64 * efer){</DIV>
<BLOCKQUOTE style="MARGIN-RIGHT: 0px" dir=ltr>
<DIV style="MARGIN-RIGHT: 0px" dir=ltr
align=left>current->vmctl.read_control_reg (CONTROL_REG_CR0,
cr0);<BR>current->vmctl.read_control_reg (CONTROL_REG_CR3,
cr3);<BR>current->vmctl.read_control_reg (CONTROL_REG_CR4,
cr4);<BR>current->vmctl.read_msr (MSR_IA32_EFER, efer);</DIV></BLOCKQUOTE>
<DIV style="MARGIN-RIGHT: 0px" dir=ltr align=left>}</DIV>
<DIV style="MARGIN-RIGHT: 0px" dir=ltr align=left> </DIV>
<DIV>But there is a little trick, that is the value of cr3 is the vcpu's
current state, which means if u are running a process A,
and A has invoked get_control_regs() to get cr3, then
the cr3's value is process A's page directory's gpa address. If u want
to convert process B's gva, it should not work.</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV>And I have another question, is there anyone can answer me? How to pause
bitvisor and resume it? I need to pause vm for consistent memory access although
it seems work good if I don't pause vm. But I still need some help or knowledge
of pausing and resuming the bitvisor.</DIV>
<DIV style="TEXT-INDENT: 2em"> </DIV>
<DIV>Augustus Liu <<A
href="mailto:hikkikuma1991@163.com">hikkikuma1991@163.com</A>></DIV>
<DIV> </DIV>
<DIV>
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id=ntes-flashmail-quote>
<DIV><STRONG>发件人：</STRONG>bitvisor-devel-en-request@bitvisor.org</DIV>
<DIV><STRONG>发送时间：</STRONG>2015-12-09 11:00</DIV>
<DIV><STRONG>主题：</STRONG>BitVisor-devel-en Digest, Vol 26, Issue 2</DIV>
<DIV><STRONG>收件人：</STRONG>"bitvisor-devel-en"<bitvisor-devel-en@bitvisor.org></DIV>
<DIV><STRONG>抄送：</STRONG></DIV>
<DIV> </DIV>
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<DIV>Today's Topics: </DIV>
<DIV> </DIV>
<DIV> 1. [BitVisor-devel-en:66] Re: How can I convert a gva to gpa? </DIV>
<DIV> (Hideki EIRAKU) </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>---------------------------------------------------------------------- </DIV>
<DIV> </DIV>
<DIV>Message: 1 </DIV>
<DIV>Date: Tue, 08 Dec 2015 15:39:09 +0900 (JST) </DIV>
<DIV>From: Hideki EIRAKU <hdk@igel.co.jp> </DIV>
<DIV>To: bitvisor-devel-en@bitvisor.org </DIV>
<DIV>Subject: [BitVisor-devel-en:66] Re: How can I convert a gva to gpa? </DIV>
<DIV>Message-ID: <20151208.153909.26311979.hdk@igel.co.jp> </DIV>
<DIV>Content-Type: Text/Plain; charset=us-ascii </DIV>
<DIV> </DIV>
<DIV>Hello, </DIV>
<DIV> </DIV>
<DIV>From: "hikkikuma1991"<hikkikuma1991@163.com> </DIV>
<DIV>Subject: [BitVisor-devel-en:65] How can I convert a gva to gpa? </DIV>
<DIV>Date: Mon, 7 Dec 2015 15:02:34 +0800 </DIV>
<DIV> </DIV>
<DIV>> But I met a problem when I tried to convert guest virtual address to guest physics address. I copied the void memdump_gvirt(u64 gvirt) fuction in "process/debug.c", but it always returned a VMMERR_PAGE_NOT_PRESENT value to me, so I want to know is this func really works, or how could I use the func to convert a gva? And if it doesn't work, would you mind giving me some advices to finish this func? By the way, my enviroment is bitvisor 1.3 with 64bit Ubuntu 12.04. </DIV>
<DIV> </DIV>
<DIV>The memdump_gvirt() function in core/debug.c uses the </DIV>
<DIV>cpu_mmu_get_pte() function to convert virtual address to physical </DIV>
<DIV>address. The cpu_mmu_get_pte() function requires register values of </DIV>
<DIV>cr0, cr3, cr4, and, efer. Those registers contain information about </DIV>
<DIV>page tables. The cpu_mmu_get_pte() function should work properly </DIV>
<DIV>because it is used by instruction interpretation for real-address mode </DIV>
<DIV>emulation for old processors like Intel Core 2 Duo. </DIV>
<DIV> </DIV>
<DIV>To convert address of current running process or kernel in the guest </DIV>
<DIV>operating system, use current->vmctl.read_control_reg() and </DIV>
<DIV>current->vmctl.read_msr() function to get those registers, then use </DIV>
<DIV>the cpu_mmu_get_pte() function. Functions such as read_linearaddr_b() </DIV>
<DIV>in core/cpu_mmu.c use this way. </DIV>
<DIV> </DIV>
<DIV>VMMERR_PAGE_NOT_PRESENT means the page is not present. For example, </DIV>
<DIV>if the virtual address is zero, usually the page is not present </DIV>
<DIV>because it is NULL pointer address. For another example, a page that </DIV>
<DIV>a process allocated may not be present because of deferred page </DIV>
<DIV>allocation or swapping. </DIV>
<DIV> </DIV>
<DIV>-- </DIV>
<DIV>Hideki EIRAKU <hdk@igel.co.jp> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV>------------------------------ </DIV>
<DIV> </DIV>
<DIV>Subject: Digest Footer </DIV>
<DIV> </DIV>
<DIV>_______________________________________________ </DIV>
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<DIV>------------------------------ </DIV>
<DIV> </DIV>
<DIV>End of BitVisor-devel-en Digest, Vol 26, Issue 2 </DIV>
<DIV>************************************************ </DIV></DIV></BLOCKQUOTE></BODY></HTML>