On Thursday 04 Feb 2021 at 14:31:08 (+0000), Will Deacon wrote: > On Wed, Feb 03, 2021 at 06:33:30PM +0000, Quentin Perret wrote: > > On Tuesday 02 Feb 2021 at 18:13:08 (+0000), Will Deacon wrote: > > > On Fri, Jan 08, 2021 at 12:15:10PM +0000, Quentin Perret wrote: > > > > + * __find_buddy(pool, page 0, order 0) => page 1 > > > > + * __find_buddy(pool, page 0, order 1) => page 2 > > > > + * __find_buddy(pool, page 1, order 0) => page 0 > > > > + * __find_buddy(pool, page 2, order 0) => page 3 > > > > + */ > > > > +static struct hyp_page *__find_buddy(struct hyp_pool *pool, struct > > > > hyp_page *p, > > > > + unsigned int order) > > > > +{ > > > > + phys_addr_t addr = hyp_page_to_phys(p); > > > > + > > > > + addr ^= (PAGE_SIZE << order); > > > > + if (addr < pool->range_start || addr >= pool->range_end) > > > > + return NULL; > > > > > > Are these range checks only needed because the pool isn't required to be > > > an exact power-of-2 pages in size? If so, maybe it would be more > > > straightforward to limit the max order on a per-pool basis depending upon > > > its size? > > > > More importantly, it is because pages outside of the pool are not > > guaranteed to be covered by the hyp_vmemmap, so I really need to make > > sure I don't dereference them. > > Wouldn't having a per-pool max order help with that?
The issue is, I have no alignment guarantees for the pools, so I may end up with max_order = 0 ... _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm