>>> On 14.11.17 at 07:53, <yu.c.zh...@linux.intel.com> wrote: > In modify_xen_mappings(), a L1/L2 page table shall be freed, > if all entries of this page table are empty. Corresponding > L2/L3 PTE will need be cleared in such scenario. > > However, concurrent paging structure modifications on different > CPUs may cause the L2/L3 PTEs to be already be cleared or set > to reference a superpage. > > Therefore the logic to enumerate the L1/L2 page table and to > reset the corresponding L2/L3 PTE need to be protected with > spinlock. And the _PAGE_PRESENT and _PAGE_PSE flags need be > checked after the lock is obtained. > > Signed-off-by: Yu Zhang <yu.c.zh...@linux.intel.com>
Reviewed-by: Jan Beulich <jbeul...@suse.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
