On 17/11/2020 16:07, Catalin Marinas wrote:
Hi Steven, On Mon, Oct 26, 2020 at 03:57:27PM +0000, Steven Price wrote:diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 19aacc7d64de..38fe25310ca1 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -862,6 +862,26 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (vma_pagesize == PAGE_SIZE && !force_pte) vma_pagesize = transparent_hugepage_adjust(memslot, hva, &pfn, &fault_ipa); + + /* + * The otherwise redundant test for system_supports_mte() allows the + * code to be compiled out when CONFIG_ARM64_MTE is not present. + */ + if (system_supports_mte() && kvm->arch.mte_enabled && pfn_valid(pfn)) { + /* + * VM will be able to see the page's tags, so we must ensure + * they have been initialised. + */ + struct page *page = pfn_to_page(pfn); + long i, nr_pages = compound_nr(page); + + /* if PG_mte_tagged is set, tags have already been initialised */ + for (i = 0; i < nr_pages; i++, page++) { + if (!test_and_set_bit(PG_mte_tagged, &page->flags)) + mte_clear_page_tags(page_address(page)); + } + }If this page was swapped out and mapped back in, where does the restoring from swap happen?
Restoring from swap happens above this in the call to gfn_to_pfn_prot()
I may have asked in the past, is user_mem_abort() the only path for mapping Normal pages into stage 2?
That is my understanding (and yes you asked before) and no one has corrected me! ;)
Steve _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
