Re: [PATCH mm-unstable v1 04/20] mm: add early FAULT_FLAG_UNSHARE consistency checks

On 11/16/22 11:26, David Hildenbrand wrote:

For now, FAULT_FLAG_UNSHARE only applies to anonymous pages, which implies a COW mapping. Let's hide FAULT_FLAG_UNSHARE early if we're not dealing with a COW mapping, such that we treat it like a read fault as documented and don't have to worry about the flag throughout all fault handlers.

While at it, centralize the check for mutual exclusion of FAULT_FLAG_UNSHARE and FAULT_FLAG_WRITE and just drop the check that either flag is set in the WP handler.

Signed-off-by: David Hildenbrand david@redhat.com

mm/huge_memory.c | 3 --- mm/hugetlb.c | 5 ----- mm/memory.c | 23 ++++++++++++++++++++--- 3 files changed, 20 insertions(+), 11 deletions(-)

Reviewed-by: Vlastimil Babka vbabka@suse.cz