| Message ID | 20210512043107.30076-2-zhenzhong.duan@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | selftests: kvm: Fix a potential elf loading issue | expand |
On 12/05/21 06:31, Zhenzhong Duan wrote: > vm_vaddr_alloc() setup GVA to GPA mapping page by page, then GPA may not be > continuous if same memslot is used for data and page table allocation. > > kvm_vm_elf_load() expects a continuous memory of GPA or else it need to > read file data page by page. Fix it by adding a check in vm_vaddr_alloc() > to ensure memory is allocated in a whole if same memslot is used for data > and page table. > > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> > --- Why not do diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 7426163d448a..f362a066f37a 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1170,6 +1170,9 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min, uint64_t pages = (sz >> vm->page_shift) + ((sz % vm->page_size) != 0); virt_pgd_alloc(vm, pgd_memslot); + vm_paddr_t paddr = vm_phy_pages_alloc(vm, pages, + KVM_UTIL_MIN_PFN * vm->page_size, + data_memslot); /* * Find an unused range of virtual page addresses of at least @@ -1179,11 +1182,7 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min, /* Map the virtual pages. */ for (vm_vaddr_t vaddr = vaddr_start; pages > 0; - pages--, vaddr += vm->page_size) { - vm_paddr_t paddr; - - paddr = vm_phy_page_alloc(vm, - KVM_UTIL_MIN_PFN * vm->page_size, data_memslot); + pages--, vaddr += vm->page_size, paddr += vm->page_size) { virt_pg_map(vm, vaddr, paddr, pgd_memslot); instead? Paolo
> -----Original Message----- > From: Paolo Bonzini <pbonzini@redhat.com> > Sent: Monday, May 24, 2021 8:28 PM > To: Duan, Zhenzhong <zhenzhong.duan@intel.com>; linux- > kernel@vger.kernel.org > Cc: linux-kselftest@vger.kernel.org; kvm@vger.kernel.org; shuah@kernel.org > Subject: Re: [PATCH] selftests: kvm: Fix a potential elf loading issue > > On 12/05/21 06:31, Zhenzhong Duan wrote: > > vm_vaddr_alloc() setup GVA to GPA mapping page by page, then GPA may > > not be continuous if same memslot is used for data and page table > allocation. > > > > kvm_vm_elf_load() expects a continuous memory of GPA or else it need > > to read file data page by page. Fix it by adding a check in > > vm_vaddr_alloc() to ensure memory is allocated in a whole if same > > memslot is used for data and page table. > > > > Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> > > --- > Why not do > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c > b/tools/testing/selftests/kvm/lib/kvm_util.c > index 7426163d448a..f362a066f37a 100644 > --- a/tools/testing/selftests/kvm/lib/kvm_util.c > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c > @@ -1170,6 +1170,9 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, > size_t sz, vm_vaddr_t vaddr_min, > uint64_t pages = (sz >> vm->page_shift) + ((sz % vm->page_size) != 0); > > virt_pgd_alloc(vm, pgd_memslot); > + vm_paddr_t paddr = vm_phy_pages_alloc(vm, pages, > + KVM_UTIL_MIN_PFN * vm- > >page_size, > + data_memslot); > > /* > * Find an unused range of virtual page addresses of at least @@ - > 1179,11 +1182,7 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, > size_t sz, vm_vaddr_t vaddr_min, > > /* Map the virtual pages. */ > for (vm_vaddr_t vaddr = vaddr_start; pages > 0; > - pages--, vaddr += vm->page_size) { > - vm_paddr_t paddr; > - > - paddr = vm_phy_page_alloc(vm, > - KVM_UTIL_MIN_PFN * vm->page_size, > data_memslot); > + pages--, vaddr += vm->page_size, paddr += vm->page_size) { > > virt_pg_map(vm, vaddr, paddr, pgd_memslot); > > > instead? Yes, this is better, thanks for fixing. Regards Zhenzhong
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index 159f4d62241d..6118a2f8906e 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -1097,9 +1097,14 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min, uint32_t data_memslot, uint32_t pgd_memslot) { uint64_t pages = (sz >> vm->page_shift) + ((sz % vm->page_size) != 0); + vm_paddr_t paddr_start = 0; virt_pgd_alloc(vm, pgd_memslot); + if (data_memslot == pgd_memslot) + paddr_start = vm_phy_pages_alloc(vm, pages, + KVM_UTIL_MIN_PFN * vm->page_size, data_memslot); + /* * Find an unused range of virtual page addresses of at least * pages in length. @@ -1111,8 +1116,12 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min, pages--, vaddr += vm->page_size) { vm_paddr_t paddr; - paddr = vm_phy_page_alloc(vm, - KVM_UTIL_MIN_PFN * vm->page_size, data_memslot); + if (paddr_start) { + paddr = paddr_start; + paddr_start += vm->page_size; + } else + paddr = vm_phy_page_alloc(vm, + KVM_UTIL_MIN_PFN * vm->page_size, data_memslot); virt_pg_map(vm, vaddr, paddr, pgd_memslot);
vm_vaddr_alloc() setup GVA to GPA mapping page by page, then GPA may not be continuous if same memslot is used for data and page table allocation. kvm_vm_elf_load() expects a continuous memory of GPA or else it need to read file data page by page. Fix it by adding a check in vm_vaddr_alloc() to ensure memory is allocated in a whole if same memslot is used for data and page table. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> --- tools/testing/selftests/kvm/lib/kvm_util.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)