similar to: page fault in shadow page-table

Hi all, Can Xen hypervisor modify HVM domU's Shadow page table, under the dom0's context, like trapped from dom0's hypercall? I think it have to call 2 functions at least: guest_walk_tables() and flush_tlb_all(). Can these 2 functions called in dom0's context? In my test, if hypervisor tries to modify HVM's shadow page table, it will bring down the whole system. I am not

One could even debate whether reserved bit faults are always fatal (and should never be propagated to the guest)... Signed-off-by: Jan Beulich <jbeulich@novell.com> Index: 2008-01-28/xen/arch/x86/traps.c =================================================================== --- 2008-01-28.orig/xen/arch/x86/traps.c 2008-01-28 11:31:44.000000000 +0100 +++ 2008-01-28/xen/arch/x86/traps.c

A post last week contained the design document for a shadow page table mechanism. This post contains more information, and a pointer to the code. As a recap, the "XI Shadow Mechanism" is a design for shadow page table code for fully virtualized HVM domains running on a 64-bit Xen hypervisor. This work was undertaken to address a number of goals. These are enumerated in the document

Hello Han, I am pleased you approve of the design and implementation of the XI shadow mechanism. And I appreciate the time and care you''ve taken in reviewing this substantial body of new code. You asked about performance statistics. With the current XI patch, we are seeing the following: - page faults times for XI are about 4 times faster than non-XI: 10.56 (non-XI) vs 2.43

Hi, Robert, I found out another confusing code snippet: in void xi_invl_mfn(struct domain *d, unsigned long mfn) if (ext && pfn < ext->large_page_aligned_size) According to the code, it should be if (ext && (pfn>>SPT_ENTRIES_ORDER) < ext->large_page_aligned_size) If I made any mistake, please point it out.

Hi, guys Recently I have been doing some research & I''ve got in trouble. I have altered the kernel of domU and put the code section and data section of selinux security server which locate ~/security/selinux/ss into two seperate sections in the final vmlinux image(see below) objdump -h vmlinux vmlinux: file format elf32-i386 Sections: Idx Name Size VMA

Trying to fire up Puppet 0.24.7 on an Ubuntu 6.06 x64 machine (yes, I know it''s obsolete, but we have a pile of machines), I get this failure: ---------------------------- # /etc/init.d/puppet start * Starting puppet configuration management tool /usr/lib/ruby/1.8/x86_64-linux/shadow.so: [BUG] Segmentation fault ruby 1.8.4 (2005-12-24) [x86_64-linux] /etc/init.d/puppet: line 35:

# HG changeset patch # User Xiaofeng Ling <xiaofeng.ling@intel.com> # Node ID cc6e19224d0b755d24358cd15d1a40f894d320b4 # Parent b215584242c43415eccd008b90c812f3d04b398d Don''t unshadow when the shadow l2 is the current used shadow table. Otherwise, when destorying the domain, if the current sl2 is unpinned, the shadow page will be freed without accquire the shadow_lock. This may

Add hypercall (shadow op: enable/disable and clean/peek dirtied page bitmap). It consists of two parts: dirty page detecting and saving. For detecting, we setup the guest p2m''s leaf PTE read-only and whenever the guest tries to write something, permission fault happens and traps into xen. The permission-faulted GPA should be saved for the toolstack (when it wants to see which pages

Hello, I''m new to Xen and especially to the hypervisor code. I''m working off a 3.0.4.1 base and have the following questions regarding the memory management code for an x86, 32-bit platform (capable of supporting PAE). I''m doing some research into providing grant table hypercall support from a Windows 2003 HVM. I have made all the necessary changes to allow the

Hello, I am studing Xen hypercall now. I found that hypercall is invoked via hypercall_page, which is only filled with (in no-hypervisor-kernel-mode ): mov $i, %eax int $0x82 ret Why not invoked the hypercall directly by "int $0x82" ? What''s the advantage of using hypercall_page? Thanks, Wu _______________________________________________ Xen-devel mailing list

Hi all, I am trying to perform single-stepping and instruction emulation both in Xen-3.2.1. I am using the following approach: First, I mark a guest page "not present" inside the shadow page table so that I could intercept any operation that involves this page. When the guest tries to access that page, it faults and control goes to Xen (sh_page_fault function). There, I emulate that

The following errata for CentOS-2 have been built and uploaded the the centos mirror. These packages are all small bug fixes except for arptables_jf which is a new package. You should also remember to uninstall netscape with this command: rpm --erase netscape-common netscape-communicator netscape-navigator RHBA-2004:155 Updated XFree86 packages fix memory faults on Itanium RHBA-2004:223

hi, How can I get corresponding shadowed page number of a virtual address in vm? -- Best Regards, Mohamad Rezaei

Hi, In many places xen uses "unsigned long" instead of the l*_pgentry_t types to pass around page table entries. Here is a patch which fixes this in a number of places (mostly in shadow mode code). Thats what I''ve trapped in so far, maybe more of these patches follow. Fixing this is needed for adding PAE support to xen. In PAE paging mode the page table entries are 64 bit

I''m porting a light weight kernel to run under the Xen hypervisor and have run into a problem while trying to switch to my page tables on x86-64. After a minor problem with switching to the new PML4 table that was cleared up when Mark Williamson suggested mapping everything read-only in the current map before switching, as well as switching the memory management code to use the

what is the relationship between virtual gdt in xen, and shadow page table of vm in xen? I want to determine the type of a page (is it data, or code) from xen. For this I have vtx, and shadow paging enabled in Dom0. I don''t have any domU running. -- Best Regards, Mohamad Rezaei

From: ?tefan ?icleru <ssicleru at bitdefender.com> Add a view mask for kvm_mmu_zap_all() in order to allow zapping shadow pages for specific EPT views. This is required when an introspected VM is unhooked. In that case, shadow pages that belong to non-default views will be zapped. Signed-off-by: ?tefan ?icleru <ssicleru at bitdefender.com> Signed-off-by: Adalbert Laz?r <alazar at

Index: 2006-10-04/xen/arch/x86/domain.c =================================================================== --- 2006-10-04.orig/xen/arch/x86/domain.c 2006-10-04 15:03:07.000000000 +0200 +++ 2006-10-04/xen/arch/x86/domain.c 2006-10-04 15:11:03.000000000 +0200 @@ -550,10 +550,10 @@ static void load_segments(struct vcpu *n /* CS longword also contains full evtchn_upcall_mask. */

Hi all, I''ve been reading through the code regarding paging --> spending a lot of time in mm/*.*, as well as some of the other parts up a level or two, but I''m still unclear as to some key things. Here''s what I think I know: I think I know how a domain''s shadow page table is first allocated E.G. the hash_table is xmalloc''ed and when it is