similar to: [PATCH] Shadow audit fix

The guest handle checks should use paging_* predicates, not shadow_*. Also tidy up a few places where p2m definitions were being imported via asm/guest_access.h -> asm/shadow.h -> asm/p2m.h Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com> -- Tim Deegan <Tim.Deegan@citrix.com> Principal Software Engineer, Citrix Systems (R&D) Ltd. [Company #02300071, SL9 0DZ, UK.]

Deal with failures in hvm_copy_from_guest_virt when fetching instructions in the various SVM emulation paths. Since we know that the instruction was fetchable by the hardware, we can usually just return from the VMEXIT and try again; whatever caused us to fail will cause the hardware to fail next time and we''ll get the correct exit code. Signed-off-by: Tim Deegan

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 all! Did the nested xen stuff make it into the xen-unstable (4.1-rc1?) tree as suggested back in January by Tim Deegan? TIA ________________________________ Date: Fri, 7 Jan 2011 16:01:12 +0000 From: Tim Deegan <Tim.Deegan@citrix.com> Subject: Re: [Xen-devel] [PATCH 00/12] Nested Virtualization: Overview To: Christoph Egger <Christoph.Egger@amd.com> Cc: Keir Fraser

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

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 .

Hi, I am really confused about NPT walks for guest page table , and eager to know the details about it. It is treated as data writes even if the access itself is a code read in AMD NPT.I just want to know : is it the same in EPT? Could anyone help me? I would like to know that very much Thank you in advance Bo Ma _______________________________________________ Xen-devel mailing list

sh_remove_all_mappings() will walk roughly half of the shadow L1 tables for each MFN it''s called with; calling it for every MFN in a guest''s framebuffer can be _very_ expensive, especially with the shadow lock held across the whole operation. Avoid that by just blowing away all the shadows. Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com>

Hi all, Can some one tell me where phys_to_machine_mapping is being initialized for a domU having paging mode set to PG_translate. I see that, populate_physmap() after calling __alloc_xen_heap_pages only updates the machine_to_physmap but how is the mfn for the allocated page being updated/set for phys_to_machine_mapping?? I see that phys_to_machine_mapping is a #defined to RO_MPT_VIRT_START

We recently observed a problem with Solaris HVM domains. The bug was seen was seen with a higher number of VCPUs (3 or more), and always had the same pattern: some memory was allocated in the guest, but the first reference caused it to crash with a fatal pagefault. However, on inspection of the page tables, the guests'' view of the pagetables was consistent: the page was present.

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

Simplify paging_invlpg when flush is not required. New ''flush'' parameter is added to paging_invlpg, to allow caller assigning whether flush check is required. It''s wasteful to always validate shadow linear mapping if caller doesn''t check return value at all. Signed-off-by Kevin Tian <kevin.tian@intel.com> Thanks, Kevin

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

Dear All: I am pretty new to xen-devel, please correct me in the following. Assume we have the following terms GPT: guest page table SPT: shadow page table (Question a) When guest OS is running, is it always using SPT for address translation? If it is the case, how does guest OS refer and modify its own GPT content? It seems that there is a page table entry in SPT for the GPT page. (Question

flight 12043 xen-unstable real [real] http://www.chiark.greenend.org.uk/~xensrcts/logs/12043/ Regressions :-( Tests which did not succeed and are blocking, including tests which could not be run: test-amd64-i386-rhel6hvm-amd 7 redhat-install fail REGR. vs. 12031 test-amd64-i386-rhel6hvm-intel 7 redhat-install fail REGR. vs. 12031 test-amd64-i386-xl-winxpsp3-vcpus1 7

With pretty trivial user mode programs being able to crash the kernel due to the ref counter widths in Xen being more narrow than in Linux, I started an attempt to put together a kernel side fix. While addressing the plain hypercalls is pretty strait forward, dealing with multicalls (both when using them for lazy mmu mode batching and when explicitly using them in e.g. netback - the backends are

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)

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