Edgecombe, Rick P wrote: > On Thu, 2024-03-14 at 09:27 -0700, Kees Cook wrote: > > On Mon, Aug 30, 2021 at 04:59:08PM -0700, Rick Edgecombe wrote: > > > This is a second RFC for the PKS write protected tables concept. > > > I'm sharing to > > > show the progress to interested people. I'd also appreciate any > > > comments, > > > especially on the direct map page table protection solution (patch > > > 17). > > > > *thread necromancy* > > > > Hi, > > > > Where does this series stand? I don't think it ever got merged? > > There are sort of three components to this: > 1. Basic PKS support. It was dropped after the main use case was > rejected (pmem stray write protection). This was the main reason it got dropped. > 2. Solution for applying direct map permissions efficiently. This > includes avoiding excessive kernel shootdowns, as well as avoiding > direct map fragmentation. rppt continued to look at the fragmentation > part of the problem and ended up arguing that it actually isn't an > issue [0]. Regardless, the shootdown problem remains for usages like > PKS tables that allocate so frequently. There is an attempt to address > both in this series. But given the above, there may be lots of debate > and opinions. > 3. The actual protection of the PKS tables (most of this series). It > got paused when I started to work on CET. In the meantime 1 was > dropped, and 2 is still open(?). So there is more to work through now, > then when it was dropped. > > If anyone wants to pick it up, it is fine by me. I can help with > reviews. I can help with reviews as well, Ira > > > [0] https://lwn.net/Articles/931406/
