Instead of using L1's stack, create a simple page allocator and use that to allocate L2 stack. The allocator will also be used later on when the stage-2 page table generator builds stage-2 mappings for the nested guest (L2).
Signed-off-by: Wei-Lin Chang <[email protected]> --- .../selftests/kvm/arm64/shadow_stage2.c | 20 ++++++++--- .../selftests/kvm/include/arm64/nested.h | 9 +++++ .../testing/selftests/kvm/lib/arm64/nested.c | 33 +++++++++++++++++++ 3 files changed, 58 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/kvm/arm64/shadow_stage2.c b/tools/testing/selftests/kvm/arm64/shadow_stage2.c index cf76a2b0582d..1ad510a38654 100644 --- a/tools/testing/selftests/kvm/arm64/shadow_stage2.c +++ b/tools/testing/selftests/kvm/arm64/shadow_stage2.c @@ -9,12 +9,16 @@ #include "ucall.h" #define XLATE2GPA (0xABCD) -#define L2STACKSZ (0x100) #define L2SUCCESS (0x0) #define L2FAILED (0x1) #define L2SYNC (0x2) +/* Used for L2 stack and guest S2 page tables. */ +#define L2_PAGE_POOL_ADDR (0x80000000) +#define L2_PAGE_POOL_NPAGES (512) +#define L2_PAGE_POOL_MEMSLOT (0x2) + /* * TPIDR_EL2 is used to store vcpu id, so save and restore it. */ @@ -48,14 +52,18 @@ static void guest_code(void) struct hyp_data hyp_data; int ret, i = 0; gpa_t l2_pc, l2_stack_top; - /* force 16-byte alignment for the stack pointer */ - u8 l2_stack[L2STACKSZ] __attribute__((aligned(16))); + struct page_pool pp; GUEST_ASSERT_EQ(get_current_el(), 2); GUEST_PRINTF("vEL2 entry\n"); + pp.start = L2_PAGE_POOL_ADDR; + pp.npages = L2_PAGE_POOL_NPAGES; + pp.current = L2_PAGE_POOL_ADDR; + pp.page_size = get_page_size(); + + l2_stack_top = alloc_page(&pp) + pp.page_size; l2_pc = ucall_translate_to_gpa(l2_guest_code); - l2_stack_top = ucall_translate_to_gpa(&l2_stack[L2STACKSZ]); init_vcpu(&vcpu, l2_pc, l2_stack_top); prepare_hyp(); @@ -96,6 +104,10 @@ int main(void) vcpu = aarch64_vcpu_add(vm, 0, &init, guest_code); kvm_arch_vm_finalize_vcpus(vm); + vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, + L2_PAGE_POOL_ADDR, L2_PAGE_POOL_MEMSLOT, + L2_PAGE_POOL_NPAGES, 0); + while (true) { vcpu_run(vcpu); diff --git a/tools/testing/selftests/kvm/include/arm64/nested.h b/tools/testing/selftests/kvm/include/arm64/nested.h index c10ef4a85be7..8e7d7738b381 100644 --- a/tools/testing/selftests/kvm/include/arm64/nested.h +++ b/tools/testing/selftests/kvm/include/arm64/nested.h @@ -46,6 +46,15 @@ struct hyp_data { struct cpu_context hyp_context; }; +struct page_pool { + gpa_t start; + gpa_t current; + size_t npages; + size_t page_size; +}; + +size_t get_page_size(void); +gpa_t alloc_page(struct page_pool *pp); void prepare_hyp(void); void init_vcpu(struct vcpu *vcpu, gpa_t l2_pc, gpa_t l2_stack_top); int run_l2(struct vcpu *vcpu, struct hyp_data *hyp_data); diff --git a/tools/testing/selftests/kvm/lib/arm64/nested.c b/tools/testing/selftests/kvm/lib/arm64/nested.c index f6c24beb01d0..7f47e340f00d 100644 --- a/tools/testing/selftests/kvm/lib/arm64/nested.c +++ b/tools/testing/selftests/kvm/lib/arm64/nested.c @@ -7,6 +7,39 @@ #include "processor.h" #include "test_util.h" #include <asm/sysreg.h> +#include <linux/sizes.h> + +size_t get_page_size(void) +{ + u64 tcr_el1 = read_sysreg(tcr_el1); + u64 tg0 = SYS_FIELD_GET(TCR_EL1, TG0, tcr_el1); + + switch (tg0) { + case TCR_EL1_TG0_4K: + return SZ_4K; + case TCR_EL1_TG0_16K: + return SZ_16K; + case TCR_EL1_TG0_64K: + return SZ_64K; + default: + GUEST_FAIL("Unexpected tg0 value!\n"); + return 0; + } +} + +gpa_t alloc_page(struct page_pool *pp) +{ + gpa_t page = pp->current; + + pp->current += pp->page_size; + + if ((pp->current - pp->start) / pp->page_size <= pp->npages) { + return page; + } else { + GUEST_FAIL("%s failed!\n", __func__); + return 0; + } +} void prepare_hyp(void) { -- 2.43.0
