On Fri, 16 Mar 2018, Dave Hansen wrote: > > From: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> > > mm_pkey_is_allocated() treats pkey 0 as unallocated. That is > inconsistent with the manpages, and also inconsistent with > mm->context.pkey_allocation_map. Stop special casing it and only > disallow values that are actually bad (< 0). > > The end-user visible effect of this is that you can now use > mprotect_pkey() to set pkey=0. > > This is a bit nicer than what Ram proposed because it is simpler > and removes special-casing for pkey 0. On the other hand, it does > allow applciations to pkey_free() pkey-0, but that's just a silly > thing to do, so we are not going to protect against it. What's the consequence of that? Application crashing and burning itself or something more subtle? Thanks, tglx
