On Tue, Jun 11, 2024 at 11:20:01AM -0400, Peter Xu wrote: > On Tue, Jun 11, 2024 at 05:08:45PM +0200, Oscar Salvador wrote: > > The problem is that we do not have spare bits for 8xx to mark these ptes > > as cont-ptes or mark them pte as 8MB, so I do not see a clear path on how > > we could remove huge_ptep_get for 8xx. > > Right, I remember I thought about this too when I initially looked at one > previous version of the series, I didn't come up yet with a good solution, > but I guess we probably need to get rid of hugepd first anyway. We may > somehow still need to identify this is a 8M large leaf, and I guess this is > again the only special case where contpte can go over >1 pmds. Yes, we definitely need first to get rid of hugepd, which is a huge step, and one step closer to our goal, but at some point we will have to see what can we do about 8MB cont-ptes for 8xx and how to mark them, so ptep_get can work the same way as e.g: arm64 (ptep_get->contpte_ptep_get). @Christophe: Can you think of a way to flag those ptes? (e.g: a combination of bits etc) > I'll leave this to Christophe, but IIUC thp is only PMD_ORDER sized, so > shouldn't apply to the 8MB pages. That might be it, yes. -- Oscar Salvador SUSE Labs
