search for: pfnmap

direct_remap_pfn_range() does not properly mark vma with VM_PFNMAP. This triggers improper reference counting on what rmap thought was a normal page, and a subsequent BUG() such as: Eeek! page_mapcount(page) went negative! (-1) page->flags = 414 page->count = 1 page->mapping = 00000000 ------------[ cut here ]------------ kernel BUG at /home/chrisw...

...l_page() specificaly for which you have to return NULL all the > > time). > > > > To mirror target process memory you can use hmm_mirror, when you > > populate the inspector process page table you use insert_pfn() (mmap of > > the kvm device file must mark this vma as PFNMAP). > > > > By following the hmm_mirror API, anytime the target process has a change in > > its page table (ie virtual address -> page) you will get a callback and all you > > have to do is clear the page table within the inspector process and flush tlb > > (use zap_...

The only time when granted pages need to be treated specially is when using Xen''s PTE modification for grant mappings owned by another domain. Otherwise, the area does not require VM_DONTCOPY and VM_PFNMAP, since it can be accessed just like any other page of RAM. Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov> --- drivers/xen/gntalloc.c | 14 ++++++++++++-- drivers/xen/gntdev.c | 16 ++++++++++++++-- 2 files changed, 26 insertions(+), 4 deletions(-) diff --git a/drivers/xen/gnt...

From: Mircea C?rjaliu <mcirjaliu at bitdefender.com> The following two new mm exports are introduced: * mm_remote_map(struct mm_struct *req_mm, unsigned long req_hva, unsigned long map_hva) * mm_remote_unmap(unsigned long map_hva) * mm_remote_reset(void) * rmap_walk_remote(struct page *page, struct rmap_walk_control *rwc) This patch