On Tue, Dec 13, 2022 at 8:54 PM Lai Jiangshan <jiangshanlai@xxxxxxxxx> wrote: > > From: Lai Jiangshan <jiangshan.ljs@xxxxxxxxxxxx> > > FNAME(is_self_change_mapping) has two functionalities. > > If the fault is on a huge page but at least one of the pagetable on > the walk is also on the terminal huge page, disable the huge page > mapping for the fault. > > If the fault is modifying at least one of the pagetable on the walk, > set something to tell the emulator. > > The first functionality is much better handled by kvm_mmu_hugepage_adjust() > now, and it has a defect that it blindly disables the huge page mapping > rather than trying to reduce the size of the huge page first. > > Huang Hang reported that when a guest is writing to a 1G page, but > only a 4K page is mapped because of the first functionality in a case > in which we think a 2M page should be mapped. The 1G page includes > a pagetable on the pagetable-walk, but the narrowed 2M page doesn't. > > To fix the problem, remove FNAME(is_self_change_mapping) for its first > functionality is already and better handled by kvm_mmu_hugepage_adjust(), > and re-implement the second functionality in FNAME(fetch). > > Reported-by: Huang Hang <hhuang@xxxxxxxxxxxxxxxxx> > Signed-off-by: Lai Jiangshan <jiangshan.ljs@xxxxxxxxxxxx> > --- Hello, Ping. Thanks Lai
