similar to: xenpaing: one way to avoid paging out the page, when the corresponding mfn is in use.

Hi, Olaf we have tested the xenpaging feature and found some problems. (1) the test case like this : when we start a VM with POD enable, the xenpaging is started at the same time. this case will cause many problems ,finally, we fixed the BUG, the patch is attached below. (2) there is a very serious problem. we have observed many VM crash examples, the error code is not always the same.

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

By default, the function add_to_physmap_one set mfn to 0. Some code paths that result to an error, continue and the map the mfn 0 (valid on ARM) to the slot given by the guest. To fix the problem, return directly an error if sanity check has failed. Signed-off-by: Julien Grall <julien.grall@linaro.org> --- xen/arch/arm/mm.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git

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)

I am using Xen 3.0.4 vmx (on Intel VT). I need to map in a foreign page, given its mfn (not gpfn), into dom0. I used to do this quite well with Xen 3.0.2. However, when I ported my code to Xen 3.0.4, things seem to have changed. Does xc_map_foreign_range accept an mfn or a gpfn as its argument? It seems to be accepting gpfn in 3.0.4. Is that true? If so, can anyone please suggest a way for

With the lake of iommu, dom0 must have a 1:1 memory mapping for all these guest physical address. When the ballon decides to give back a page to the kernel, this page must have the same address as previously. Otherwise, we will loose the 1:1 mapping and will break DMA-capable device. Signed-off-by: Julien Grall <julien.grall@linaro.org> CC: Keir Fraser <keir@xen.org> CC: Jan Beulich

Hi, kdb: to debug xen hypervisor, could also debug guests gdbsx: to debug PV/HVM linux guests The tree is : http://xenbits.xensource.com/ext/debuggers.hg See README-dbg. You''ll need to setup serial access for kdb. Thanks, Mukesh > > Hi Dan, > > I''m currently using your version of ssplitd as it is. I haven''t tried > kdb. For some reason I

The following two patches allow the parallel use of memsharing, xenpaging and xen-access by using an independent ring buffer for each feature. Please review. v2: - update mem_event_check_ring arguments, check domain rather than domain_id - check ring_full first because its value was just evaluated - check if ring buffer is initialized before calling mem_access_domctl/mem_paging_domctl

A number of build problems crept in once again. Fix them. Signed-off-by: Jan Beulich <jbeulich@suse.com> --- a/xen/common/memory.c +++ b/xen/common/memory.c @@ -683,7 +683,7 @@ long do_memory_op(unsigned long cmd, XEN mfn = get_gfn_untyped(d, xrfp.gpfn); if ( mfn_valid(mfn) ) - guest_physmap_remove_page(d, xrfp.gpfn, mfn, PAGE_ORDER_4K); +

2011/7/19 Stefano Stabellini <stefano.stabellini@eu.citrix.com>: > CC''ing Tim and xen-devel > > On Mon, 18 Jul 2011, Jiageng Yu wrote: >> 2011/7/16 Stefano Stabellini <stefano.stabellini@eu.citrix.com>: >> > On Fri, 15 Jul 2011, Jiageng Yu wrote: >> >> 2011/7/15 Jiageng Yu <yujiageng734@gmail.com>: >> >> > 2011/7/15

Hi, Can anybody advise me how to debug this crash? it happens when I try to start a 32 bit kernel on my 64 bit Xen system, the kernel is my own using opensuse 11.1 rc1 2.6.27.7 xen patches, the kernel works as 32 and 64 bit dom0, and as 64 bit domU PV, is there a technique to find out where in the kernel source the crash happens? i.e what line in the source code? (XEN) mm.c:707:d49 Error getting

# HG changeset patch # User Patrick Colp <Patrick.Colp@citrix.com> # Date 1249555177 -3600 # Node ID 684c8fc69d658d058246eb9edfc8eba187ae6f2c # Parent 68e8b8379244e293c55875e7dc3692fc81d3d212 hvm emul: fix cmpxchg emulation to use an atomic operation. Currently HVM cmpxchg emulation is done by doing a normal emulated write, which is not atomic. This patch changes it to use a cmpxchg

CC''ing Tim and xen-devel On Mon, 18 Jul 2011, Jiageng Yu wrote: > 2011/7/16 Stefano Stabellini <stefano.stabellini@eu.citrix.com>: > > On Fri, 15 Jul 2011, Jiageng Yu wrote: > >> 2011/7/15 Jiageng Yu <yujiageng734@gmail.com>: > >> > 2011/7/15 Stefano Stabellini <stefano.stabellini@eu.citrix.com>: > >> >> On Fri, 15 Jul 2011,

Hi, V6: The only change from V5 is in patch #6: - changed comment to reflect autoxlate - removed a redundant ASSERT - reworked logic a bit so that get_page_from_gfn() is called with NULL for p2m type as before. arm has ASSERT wanting it to be NULL. Tim: patch 4 needs your approval. Daniel: patch 5 needs your approval. These patches implement PVH dom0. Patches 1 and 2

(This is a continuation of "[PATCH v9] xen/grant-table: Avoid m2p_override during mapping") The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the bulk of the original function (everything after the mapping

(This is a continuation of "[PATCH v9] xen/grant-table: Avoid m2p_override during mapping") The grant mapping API does m2p_override unnecessarily: only gntdev needs it, for blkback and future netback patches it just cause a lock contention, as those pages never go to userspace. Therefore this series does the following: - the bulk of the original function (everything after the mapping

Hi, I hope I''m right here. If not then please point me in the right direction. My problem in short: I have problems using (pinning, mmu_update) physical pages from 0x900000 to 0xB1000 usualy. I''m writing my own little amd64 64bit toy kernel (based on Mini-OS as starting point) for xen and I run into problems with the way the start of day sets up the physical pages. My kernel

While looking at the origin of very frequently executed hypercalls (as usual, kernel builds are what''s being measured), I realized that the high page accessor functions in Linux would be good candidates to handle in the hypervisor - clearing or copying to/from a high page is a pretty frequent operation (provided there''s enough memory). However, the measured results

Hi, I have allocated few order=9 pages in Xen memory space using alloc_domheap_pages(NULL,9,0) during boot time just before domain is created (dom0 = domain_create(0, DOMCRF_s3_integrity, DOM0_SSIDREF) in xen/arch/x86/setup.c). I got the following virtual addresses in xen log message- (XEN) a2k2: Virt_addr:ffff83011cc00000 MFN:11cc00 (XEN) a2k2: Virt_addr:ffff83011ca00000 MFN:11ca00 (XEN)

ging_prep ensures that an mfn is backing the paged-out gfn, and transitions to the next state in the paging state machine for this page. Foreign mappings of the gfn will now succeed. This is the key idea, as it allows the pager to now map the gfn and fill in its contents. Unfortunately, it also allows any other foreign mapper to map the gfn and read its contents. This is particularly dangerous