On Thu, 24 Jun 2021 04:57:47 +0100, David Stevens stevensd@chromium.org wrote:
From: David Stevens stevensd@chromium.org
Avoid converting pfns returned by follow_fault_pfn to struct pages to transiently take a reference. The reference was originally taken to match the reference taken by gup. However, pfns returned by follow_fault_pfn may not have a struct page set up for reference counting.
Signed-off-by: David Stevens stevensd@chromium.org
arch/arm64/kvm/mmu.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-)
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 896b3644b36f..a741972cb75f 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c
[...]
@@ -968,16 +968,16 @@ 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);
&pfnpg, &fault_ipa);if (writable) prot |= KVM_PGTABLE_PROT_W;
if (fault_status != FSC_PERM && !device)
clean_dcache_guest_page(pfn, vma_pagesize);
clean_dcache_guest_page(pfnpg.pfn, vma_pagesize);if (exec_fault) { prot |= KVM_PGTABLE_PROT_X;
invalidate_icache_guest_page(pfn, vma_pagesize);
invalidate_icache_guest_page(pfnpg.pfn, vma_pagesize);
This is going to clash with what is currently in -next, specially with MTE.
Paolo, if you really want to take this in 5.13, can you please push a stable branch based on -rc4 or older so that I can merge it in and test it?
Thanks,
M.