> 4.9-stable review patch. If anyone has any objections, please let me know.
I know that my response comes late but I just found out that the version of the patch applied in 4.9-stable, the one in this email, is different than the one applied on 4.14-stable. This is the one applied on 4.14: https://patchwork.kernel.org/patch/10177715/ As you can see, the check against PMD_SIZE which is present in 4.14 is not present in this version of the patch. Am I missing something or should I send a patch to rectify this? Thanks, Ioana Ciornei > > ------------------ > > From: Punit Agrawal <punit.agra...@arm.com> > > commit c507babf10ead4d5c8cca704539b170752a8ac84 upstream. > > KVM only supports PMD hugepages at stage 2 but doesn't actually check that > the provided hugepage memory pagesize is PMD_SIZE before populating > stage 2 entries. > > In cases where the backing hugepage size is smaller than PMD_SIZE (such as > when using contiguous hugepages), KVM can end up creating stage 2 > mappings that extend beyond the supplied memory. > > Fix this by checking for the pagesize of userspace vma before creating PMD > hugepage at stage 2. > > Fixes: 66b3923a1a0f77a ("arm64: hugetlb: add support for PTE contiguous > bit") > Signed-off-by: Punit Agrawal <punit.agra...@arm.com> > Cc: Marc Zyngier <marc.zyng...@arm.com> > Reviewed-by: Christoffer Dall <christoffer.d...@linaro.org> > Signed-off-by: Christoffer Dall <christoffer.d...@linaro.org> > Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> > > --- > arch/arm/kvm/mmu.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > --- a/arch/arm/kvm/mmu.c > +++ b/arch/arm/kvm/mmu.c > @@ -1284,7 +1284,7 @@ static int user_mem_abort(struct kvm_vcp > return -EFAULT; > } > > - if (is_vm_hugetlb_page(vma) && !logging_active) { > + if (vma_kernel_pagesize(vma) && !logging_active) { > hugetlb = true; > gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT; > } else { >
