similar to: EPT walks for guest 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

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

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

I want to know any difference between writing, reading and shadow page table (for example performance). I am thankful for any help or resource for that. -- Best Regards Mohamad Taghi Mir Mohamad Rezaie Iran University of Science and Technology Department of Computer Science & Engineering System Software Group _______________________________________________ Xen-devel mailing list

This fixes a bug in changeset 22526:7a5ee3800417, where the wrong value is read when deciding whether to flush the VTd tables. The effect is minor: in situations where the p2m entry is changed but the mfn is the same, the VTd tables will be unnecessarily flushed. old_entry is left untouched in the second case, since having a present old_entry will cause the an unnecessary check to be taken at

The patch attached is to set effective memory type for EPT according to the VT-d snoop control capability, and also includes some cleansup for EPT & VT-d both enabled. Signed-off-by: Zhai, Edwin Edwin.Zhai@intel.com<mailto:Edwin.Zhai@intel.com> Signed-off-by: Xin, Xiaohui xiaohui.xin@intel.com<mailto:xiaohui.xin@intel.com> _______________________________________________

Just found this patch in house which I thought sent out already. :-) Still one thing remaining is to special case for UP guest which suffers overhead from this change... ---- Remove lock on first guest table walk Existing shadow fault path grabs big lock before walking guest tables, to ensure consistency with shadow content lest concurrent change from other vcpu in a bad OS. But this lock

Hi, all Page offline can be used by many purpose, like memory offline, memory power management, proactive action when multiple CE error happen to one page etc. In virtualization environment without guest offline support, we think offline a page usually means replace the old page with a new one transparently to guest. Currently we are trying to add page offline support in Xen environment .

Attached are the patches to support super page with EPT. We only support 2M size. And shadow may still work fine with 4K pages. The patches can be split into 3 parts. Apply order is as attached. tool.diff To allocate 2M physical contiguous memory in guest except the first 2M and the last 2M. The first 2M covers special memory, and Xen use the last few pages in guest memory to do special

From: Zhang Xiantao <xiantao.zhang@intel.com> With virtual EPT support, L1 hyerpvisor can use EPT hardware for L2 guest''s memory virtualization. In this way, L2 guest''s performance can be improved sharply. According to our testing, some benchmarks can show > 5x performance gain. Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com> Zhang Xiantao (11):

Hi Tim, Could you please have a look at this bug? Thanks a lot. http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1774 Best Regards, Yongjie Ren (Jay) _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel

Trying to migrate a 64bit PV guest with 64GB running medium to heavy load on xen 3.4.0, it is showing lot of soft lockups. The softlockups are causing dom0 reboot by the cluster FS. The hardware has 256GB and 32 CPUs. Looking into the hypervisor thru kdb, I see one cpu in sh_resync_all() while all other 31 appear spinning on the shadow_lock. I vaguely remember seeing some thread on this while

There has been some progress, but still no joy. Definitely not intended for inclusion at this point. Tim, Wei, I added a Xen command line toggle to disable IOMMU and P2M table sharing. Tim, I verified that changes to p2m-pt.c don''t break shadow mode (64bit hypervisor and Win 7 guest). Hongkaixing, I incorporated your suggestion in patch 2, so I should add your Signed-off-by eventually.

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

We''ve got reports of that change causing HVM data corruption issues. While I can''t see what''s wrong with the patch, I''d suggest at least reverting it from the 3.3 tree (which is what our code is based upon) for the time being. Jan _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com

I''m not seeing the problem that Fan Zhao is reporting, instead I get this one. Not sure if ti''s the same one or a different problem... This happens with my simple-guest [i.e. not using hvmloader, as I described before]. This worked fine yesterday. (XEN) event_channel.c:178:d0 EVTCHNOP failure: domain 0, error -22, line 178 (XEN) bad shared page: 0 (XEN) domain_crash_sync called

The patch deals with the situation which guest OS uses unused page table pages as data pages and write data to them. The pages will still be grabbed by Xen as page table pages, and lots of unnecessary page faults occur. The patch will check if the data guest writes to the page table contains valid mfn or not, if not, we believe it is a data page now and then unshadow the page. The patch

Hi, I looked at the function xc_translate_foreign_address(), and see that it walks the page table of the guest VM. So at best, it should return the pfn of the guest (?) We can see taht the Later part of the function is like this: ... if (pt_levels >= 3) mfn = (pte & L0_PAGETABLE_MASK_PAE) >> PAGE_SHIFT; else mfn = (pte & L0_PAGETABLE_MASK)

This patch series tidies up a few bits ofthe nested p2m code. The main thing it does is reorganize the locking so that most of the changes to nested p2m tables happen only under the p2m lock, and the nestedp2m lock is only needed to reassign p2m tables to new cr3 values. Changes since v1: - a few minor fixes - more sensible flushing policy in p2m_get_nestedp2m() - smoke-tested this time!