Here is a batch of long-standing THP bug fixes that I had not got around to sending before, but prompted now by Wang Yugui's report https://lore.kernel.org/linux-mm/20210412180659.B9E3.409509F4@xxxxxxxxxxxx/ Wang Yugui has tested a rollup of these fixes applied to 5.10.39, and they have done no harm, but have *not* fixed that issue: something more is needed and I have no idea of what. But at least these clear up related issues, and should go to stable (except for the last, which is just an optimization: it would be fine in stable, but it's not required there). These are against 5.13-rc4: easy for others to try out, but my next task is to work out how to shoehorn them into mmotm and linux-next. I would have said just before Yang Shi's related mm-thp-replace-debug_vm-bug-with-vm_warn-when-unmap-fails-for-split.patch except that (which should also go to stable) is currently placed after Alistair Popple's "Add support for SVM atomics in Nouveau" series, mm-rmap-split-try_to_munlock-from-try_to_unmap.patch etc. I expect I shall offer you some rediffs of Alistair's, we'll see. 1/7 mm/thp: fix __split_huge_pmd_locked() on shmem migration entry 2/7 mm/thp: try_to_unmap() use TTU_SYNC for safe DEBUG_VM splitting 3/7 mm/thp: fix vma_address() if virtual address below file offset 4/7 mm/thp: fix page_address_in_vma() on file THP tails 5/7 mm/thp: fix page_vma_mapped_walk() if huge page mapped by ptes 6/7 mm/thp: unmap_mapping_page() to fix THP truncate_cleanup_page() 7/7 mm/thp: remap_page() is only needed on anonymous THP include/linux/mm.h | 3 include/linux/rmap.h | 3 mm/huge_memory.c | 47 ++++++++---- mm/internal.h | 54 ++++++++++---- mm/memory.c | 40 ++++++++++ mm/page_vma_mapped.c | 163 ++++++++++++++++++++++++++----------------- mm/pgtable-generic.c | 5 - mm/rmap.c | 39 +++++++--- mm/truncate.c | 43 +++++------ 9 files changed, 266 insertions(+), 131 deletions(-) Hugh
