[PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation
rppt at kernel.org
Thu Feb 4 04:58:55 EST 2021
On Wed, Feb 03, 2021 at 10:12:22AM +0100, Michal Hocko wrote:
> On Tue 02-02-21 21:10:40, Mike Rapoport wrote:
> > Let me reiterate to make sure I don't misread your suggestion.
> > If we make secretmem an opt-in feature with, e.g. kernel parameter, the
> > pooling of large pages is unnecessary. In this case there is no limited
> > resource we need to protect because secretmem will allocate page by page.
> > Since there is no limited resource, we don't need special permissions
> > to access secretmem so we can move forward with a system call that creates
> > a mmapable file descriptor and save the hassle of a chardev.
> Yes, I assume you implicitly assume mlock rlimit here.
> Also memcg accounting should be in place.
Right, without pools memcg accounting is no different from other
> Wrt to the specific syscall, please document why existing interfaces are
> not a good fit as well. It would be also great to describe interaction
> with mlock itself (I assume the two to be incompatible - mlock will fail
> on and mlockall will ignore it).
The interaction with mlock() belongs more to the man page, but I don't mind
adding this to changelog as well.
More information about the linux-arm-kernel