> On 13 Dec 2019, at 19:50, Sean Christopherson > <[email protected]> wrote: > > On Fri, Dec 13, 2019 at 07:31:55PM +0200, Liran Alon wrote: >> >>> On 13 Dec 2019, at 19:19, Sean Christopherson >>> <[email protected]> wrote: >>> >>> Then allowed_hugepage_adjust() would look something like: >>> >>> static void allowed_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn, >>> kvm_pfn_t *pfnp, int *levelp, int max_level) >>> { >>> kvm_pfn_t pfn = *pfnp; >>> int level = *levelp; >>> unsigned long mask; >>> >>> if (is_error_noslot_pfn(pfn) || !kvm_is_reserved_pfn(pfn) || >>> level == PT_PAGE_TABLE_LEVEL) >>> return; >>> >>> /* >>> * mmu_notifier_retry() was successful and mmu_lock is held, so >>> * the pmd/pud can't be split from under us. >>> */ >>> level = host_pfn_mapping_level(vcpu->kvm, gfn, pfn); >>> >>> *levelp = level = min(level, max_level); >>> mask = KVM_PAGES_PER_HPAGE(level) - 1; >>> VM_BUG_ON((gfn & mask) != (pfn & mask)); >>> *pfnp = pfn & ~mask; >> >> Why don’t you still need to kvm_release_pfn_clean() for original pfn and >> kvm_get_pfn() for new huge-page start pfn? > > That code is gone in kvm/queue. thp_adjust() is now called from > __direct_map() and FNAME(fetch), and so its pfn adjustment doesn't bleed > back to the page fault handlers. The only reason the put/get pfn code > existed was because the page fault handlers called kvm_release_pfn_clean() > on the pfn, i.e. they would have put the wrong pfn.
Ack. Thanks for the explaining this. _______________________________________________ Linux-nvdimm mailing list -- [email protected] To unsubscribe send an email to [email protected]
