On Sun, 2023-03-12 at 14:26 +0300, Kirill A. Shutemov 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. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > Tested-by: Alexander Potapenko <glider@xxxxxxxxxx> Seems to cover all the untagged_addr() cases that were operating on a non-current MM. Reviewed-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
