On Fri, 2 Jun 2017 12:28:48 +0200
Heiko Carstens <heiko.carstens@xxxxxxxxxx> wrote:
> On Fri, Jun 02, 2017 at 11:46:47AM +0200, Martin Schwidefsky wrote:
> > On Fri, 2 Jun 2017 09:02:10 +0200
> > Heiko Carstens <heiko.carstens@xxxxxxxxxx> wrote:
> > > Maybe this is a bit over-simplified, but might work.
> > This is not over-simplified at all, that does work:
>
> Good!
>
> > +struct arch_elf_state {
> > +};
> > +
> > +#define INIT_ARCH_ELF_STATE { }
> > +
> > +#define arch_elf_pt_proc(ehdr, phdr, elf, interp, state) (0)
> > +#define arch_check_elf(ehdr, interp, interp_ehdr, state) \
> > +({ \
> > + struct elf64_hdr *hdr = (void*) ehdr; \
> > + int _rc = 0; \
> > + if (hdr->e_ident[EI_CLASS] == ELFCLASS64 && \
> > + (hdr->e_flags & 0x00000002) && \
> > + !page_table_allocate_pgste && \
> > + !current->mm->context.alloc_pgste) { \
> > + current->mm->context.alloc_pgste = 1; \
>
> However, I think this is over-simplified, unless I'm mistaken.
>
> If you set current->mm->context.alloc_pgste here, then that means that 4k
> page tables will be freed when the original mm will be released, instead of
> the correct 2k ones.
>
> I think you need an additional intermediate context flag here. Something
> like current->mm->context.request_pgste or whatever, no?
Yes, the flags for the current mm and the next mm have to be different.
request_pgste is a nice name for the new flag, I'll use it.
--
blue skies,
Martin.
"Reality continues to ruin my life." - Calvin.
