On Mon, Jan 23, 2023 at 11:05 PM Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > > untagged_addr() removes tags/metadata from the address and brings it to > the canonical form. The helper is implemented on arm64 and sparc. Both of > them do untagging based on global rules. > > However, Linear Address Masking (LAM) on x86 introduces per-process > settings for untagging. As a result, untagged_addr() is now only > suitable for untagging addresses for the current proccess. > > The new helper untagged_addr_remote() has to be used when the address > targets remote process. It requires the mmap lock for target mm to be > taken. > > Export dump_mm() as there's now the first user for it: VFIO can be > compiled as module and untagged_addr_remote() triggers dump_mm() via > mmap_assert_locked(). > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Tested-by: Alexander Potapenko <glider@xxxxxxxxxx>
