Re: [PATCHv3 6/8] x86/mm: Provide ARCH_GET_UNTAG_MASK and ARCH_ENABLE_TAGGED_ADDR

Kirill A. Shutemov
2022-06-10T18:04:51Z

On Fri, Jun 10, 2022 at 03:25:02PM +0000, Edgecombe, Rick P wrote:
> On Fri, 2022-06-10 at 17:35 +0300, Kirill A. Shutemov wrote:
> > +static int prctl_enable_tagged_addr(unsigned long nr_bits)
> > +{
> > + struct mm_struct *mm = current->mm;
>
> do_arch_prctl_64() can be called via ptrace. I think you need to
> operate on the mm of 'task', or just block the operation if task !=
> current.

Hm. True. Let's see if the interface in general good enough.

Ouch. I just noticied that I missed check for LAM feature :/

--
Kirill A. Shutemov