From 577e022b7b41854911dcfb03678d8d2b930e8a3f Mon Sep 17 00:00:00 2001 From: Andrew Jones Date: Tue, 14 Dec 2021 16:18:42 +0100 Subject: selftests: KVM: Fix non-x86 compiling MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Attempting to compile on a non-x86 architecture fails with include/kvm_util.h: In function ‘vm_compute_max_gfn’: include/kvm_util.h:79:21: error: dereferencing pointer to incomplete type ‘struct kvm_vm’ return ((1ULL << vm->pa_bits) >> vm->page_shift) - 1; ^~ This is because the declaration of struct kvm_vm is in lib/kvm_util_internal.h as an effort to make it private to the test lib code. We can still provide arch specific functions, though, by making the generic function symbols weak. Do that to fix the compile error. Fixes: c8cc43c1eae2 ("selftests: KVM: avoid failures due to reserved HyperTransport region") Cc: stable@vger.kernel.org Signed-off-by: Andrew Jones Message-Id: <20211214151842.848314-1-drjones@redhat.com> Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/include/kvm_util.h | 10 +--------- tools/testing/selftests/kvm/lib/kvm_util.c | 5 +++++ 2 files changed, 6 insertions(+), 9 deletions(-) (limited to 'tools') diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index da2b702da71a..2d62edc49d67 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -71,15 +71,6 @@ enum vm_guest_mode { #endif -#if defined(__x86_64__) -unsigned long vm_compute_max_gfn(struct kvm_vm *vm); -#else -static inline unsigned long vm_compute_max_gfn(struct kvm_vm *vm) -{ - return ((1ULL << vm->pa_bits) >> vm->page_shift) - 1; -} -#endif - #define MIN_PAGE_SIZE (1U << MIN_PAGE_SHIFT) #define PTES_PER_MIN_PAGE ptes_per_page(MIN_PAGE_SIZE) @@ -330,6 +321,7 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm); unsigned int vm_get_page_size(struct kvm_vm *vm); unsigned int vm_get_page_shift(struct kvm_vm *vm); +unsigned long vm_compute_max_gfn(struct kvm_vm *vm); uint64_t vm_get_max_gfn(struct kvm_vm *vm); int vm_get_fd(struct kvm_vm *vm); diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c index daf6fdb217a7..53d2b5d04b82 100644 --- a/tools/testing/selftests/kvm/lib/kvm_util.c +++ b/tools/testing/selftests/kvm/lib/kvm_util.c @@ -2328,6 +2328,11 @@ unsigned int vm_get_page_shift(struct kvm_vm *vm) return vm->page_shift; } +unsigned long __attribute__((weak)) vm_compute_max_gfn(struct kvm_vm *vm) +{ + return ((1ULL << vm->pa_bits) >> vm->page_shift) - 1; +} + uint64_t vm_get_max_gfn(struct kvm_vm *vm) { return vm->max_gfn; -- cgit v1.2.3 From ab1ef34416a65ba11f66ae6435fcf0251cb46fd4 Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Tue, 7 Dec 2021 19:30:06 +0000 Subject: KVM: selftests: Add test to verify TRIPLE_FAULT on invalid L2 guest state Add a selftest to attempt to enter L2 with invalid guests state by exiting to userspace via I/O from L2, and then using KVM_SET_SREGS to set invalid guest state (marking TR unusable is arbitrary chosen for its relative simplicity). This is a regression test for a bug introduced by commit c8607e4a086f ("KVM: x86: nVMX: don't fail nested VM entry on invalid guest state if !from_vmentry"), which incorrectly set vmx->fail=true when L2 had invalid guest state and ultimately triggered a WARN due to nested_vmx_vmexit() seeing vmx->fail==true while attempting to synthesize a nested VM-Exit. The is also a functional test to verify that KVM sythesizes TRIPLE_FAULT for L2, which is somewhat arbitrary behavior, instead of emulating L2. KVM should never emulate L2 due to invalid guest state, as it's architecturally impossible for L1 to run an L2 guest with invalid state as nested VM-Enter should always fail, i.e. L1 needs to do the emulation. Stuffing state via KVM ioctl() is a non-architctural, out-of-band case, hence the TRIPLE_FAULT being rather arbitrary. Signed-off-by: Sean Christopherson Message-Id: <20211207193006.120997-5-seanjc@google.com> Reviewed-by: Maxim Levitsky Signed-off-by: Paolo Bonzini --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../kvm/x86_64/vmx_invalid_nested_guest_state.c | 105 +++++++++++++++++++++ 3 files changed, 107 insertions(+) create mode 100644 tools/testing/selftests/kvm/x86_64/vmx_invalid_nested_guest_state.c (limited to 'tools') diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 00814c0f87a6..3cb5ac5da087 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -35,6 +35,7 @@ /x86_64/vmx_apic_access_test /x86_64/vmx_close_while_nested_test /x86_64/vmx_dirty_log_test +/x86_64/vmx_invalid_nested_guest_state /x86_64/vmx_preemption_timer_test /x86_64/vmx_set_nested_state_test /x86_64/vmx_tsc_adjust_test diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index f307c9f61981..17342b575e85 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -64,6 +64,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/userspace_msr_exit_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_apic_access_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_close_while_nested_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_dirty_log_test +TEST_GEN_PROGS_x86_64 += x86_64/vmx_invalid_nested_guest_state TEST_GEN_PROGS_x86_64 += x86_64/vmx_set_nested_state_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_tsc_adjust_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_nested_tsc_scaling_test diff --git a/tools/testing/selftests/kvm/x86_64/vmx_invalid_nested_guest_state.c b/tools/testing/selftests/kvm/x86_64/vmx_invalid_nested_guest_state.c new file mode 100644 index 000000000000..489fbed4ca6f --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/vmx_invalid_nested_guest_state.c @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include "test_util.h" +#include "kvm_util.h" +#include "processor.h" +#include "vmx.h" + +#include +#include + +#include "kselftest.h" + +#define VCPU_ID 0 +#define ARBITRARY_IO_PORT 0x2000 + +static struct kvm_vm *vm; + +static void l2_guest_code(void) +{ + /* + * Generate an exit to L0 userspace, i.e. main(), via I/O to an + * arbitrary port. + */ + asm volatile("inb %%dx, %%al" + : : [port] "d" (ARBITRARY_IO_PORT) : "rax"); +} + +static void l1_guest_code(struct vmx_pages *vmx_pages) +{ +#define L2_GUEST_STACK_SIZE 64 + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + + GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages)); + GUEST_ASSERT(load_vmcs(vmx_pages)); + + /* Prepare the VMCS for L2 execution. */ + prepare_vmcs(vmx_pages, l2_guest_code, + &l2_guest_stack[L2_GUEST_STACK_SIZE]); + + /* + * L2 must be run without unrestricted guest, verify that the selftests + * library hasn't enabled it. Because KVM selftests jump directly to + * 64-bit mode, unrestricted guest support isn't required. + */ + GUEST_ASSERT(!(vmreadz(CPU_BASED_VM_EXEC_CONTROL) & CPU_BASED_ACTIVATE_SECONDARY_CONTROLS) || + !(vmreadz(SECONDARY_VM_EXEC_CONTROL) & SECONDARY_EXEC_UNRESTRICTED_GUEST)); + + GUEST_ASSERT(!vmlaunch()); + + /* L2 should triple fault after main() stuffs invalid guest state. */ + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_TRIPLE_FAULT); + GUEST_DONE(); +} + +int main(int argc, char *argv[]) +{ + vm_vaddr_t vmx_pages_gva; + struct kvm_sregs sregs; + struct kvm_run *run; + struct ucall uc; + + nested_vmx_check_supported(); + + vm = vm_create_default(VCPU_ID, 0, (void *) l1_guest_code); + + /* Allocate VMX pages and shared descriptors (vmx_pages). */ + vcpu_alloc_vmx(vm, &vmx_pages_gva); + vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva); + + vcpu_run(vm, VCPU_ID); + + run = vcpu_state(vm, VCPU_ID); + + /* + * The first exit to L0 userspace should be an I/O access from L2. + * Running L1 should launch L2 without triggering an exit to userspace. + */ + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Expected KVM_EXIT_IO, got: %u (%s)\n", + run->exit_reason, exit_reason_str(run->exit_reason)); + + TEST_ASSERT(run->io.port == ARBITRARY_IO_PORT, + "Expected IN from port %d from L2, got port %d", + ARBITRARY_IO_PORT, run->io.port); + + /* + * Stuff invalid guest state for L2 by making TR unusuable. The next + * KVM_RUN should induce a TRIPLE_FAULT in L2 as KVM doesn't support + * emulating invalid guest state for L2. + */ + memset(&sregs, 0, sizeof(sregs)); + vcpu_sregs_get(vm, VCPU_ID, &sregs); + sregs.tr.unusable = 1; + vcpu_sregs_set(vm, VCPU_ID, &sregs); + + vcpu_run(vm, VCPU_ID); + + switch (get_ucall(vm, VCPU_ID, &uc)) { + case UCALL_DONE: + break; + case UCALL_ABORT: + TEST_FAIL("%s", (const char *)uc.args[0]); + default: + TEST_FAIL("Unexpected ucall: %lu", uc.cmd); + } +} -- cgit v1.2.3