Commit 0383a8ed authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

selftests: kvm: try getting XFD and XSAVE state out of sync 



The host is allowed to set FPU state that includes a disabled
xstate component.  Check that this does not cause bad effects.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent a1025dcd

tools/testing/selftests/kvm/x86/amx_test.c

+30 −8
Original line number Diff line number Diff line
@@ -125,11 +125,17 @@ static void set_tilecfg(struct tile_config *cfg) 
}



enum {

	/* Retrieve TMM0 from guest, stash it for TEST_RESTORE_TILEDATA */

	TEST_SAVE_TILEDATA = 1,



	/* Check TMM0 against tiledata */

	TEST_COMPARE_TILEDATA = 1,

	TEST_COMPARE_TILEDATA = 2,



	/* Restore TMM0 from earlier save */

	TEST_RESTORE_TILEDATA = 4,



	/* Full VM save/restore */

	TEST_SAVE_RESTORE = 2,

	TEST_SAVE_RESTORE = 8,

};



static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg,
@@ -150,7 +156,16 @@ static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, 
	GUEST_SYNC(TEST_SAVE_RESTORE);

	/* Check save/restore when trap to userspace */

	__tileloadd(tiledata);

	GUEST_SYNC(TEST_COMPARE_TILEDATA | TEST_SAVE_RESTORE);

	GUEST_SYNC(TEST_SAVE_TILEDATA | TEST_COMPARE_TILEDATA | TEST_SAVE_RESTORE);



	/* xfd=0x40000, disable amx tiledata */

	wrmsr(MSR_IA32_XFD, XFEATURE_MASK_XTILE_DATA);



	/* host tries setting tiledata while guest XFD is set */

	GUEST_SYNC(TEST_RESTORE_TILEDATA);

	GUEST_SYNC(TEST_SAVE_RESTORE);



	wrmsr(MSR_IA32_XFD, 0);

	__tilerelease();

	GUEST_SYNC(TEST_SAVE_RESTORE);

	/*
@@ -210,10 +225,10 @@ int main(int argc, char *argv[]) 
	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm;

	struct kvm_x86_state *state;

	struct kvm_x86_state *tile_state = NULL;

	int xsave_restore_size;

	vm_vaddr_t amx_cfg, tiledata, xstate;

	struct ucall uc;

	u32 amx_offset;

	int ret;



	/*
@@ -265,20 +280,27 @@ int main(int argc, char *argv[]) 
			/* NOT REACHED */

		case UCALL_SYNC:

			++iter;

			if (uc.args[1] & TEST_SAVE_TILEDATA) {

				fprintf(stderr, "GUEST_SYNC #%d, save tiledata\n", iter);

				tile_state = vcpu_save_state(vcpu);

			}

			if (uc.args[1] & TEST_COMPARE_TILEDATA) {

				fprintf(stderr, "GUEST_SYNC #%d, check TMM0 contents\n", iter);



				/* Compacted mode, get amx offset by xsave area

				 * size subtract 8K amx size.

				 */

				amx_offset = xsave_restore_size - NUM_TILES*TILE_SIZE;

				state = vcpu_save_state(vcpu);

				void *amx_start = (void *)state->xsave + amx_offset;

				u32 amx_offset = xsave_restore_size - NUM_TILES*TILE_SIZE;

				void *amx_start = (void *)tile_state->xsave + amx_offset;

				void *tiles_data = (void *)addr_gva2hva(vm, tiledata);

				/* Only check TMM0 register, 1 tile */

				ret = memcmp(amx_start, tiles_data, TILE_SIZE);

				TEST_ASSERT(ret == 0, "memcmp failed, ret=%d", ret);

				kvm_x86_state_cleanup(state);

			}

			if (uc.args[1] & TEST_RESTORE_TILEDATA) {

				fprintf(stderr, "GUEST_SYNC #%d, before KVM_SET_XSAVE\n", iter);

				vcpu_xsave_set(vcpu, tile_state->xsave);

				fprintf(stderr, "GUEST_SYNC #%d, after KVM_SET_XSAVE\n", iter);

			}

			if (uc.args[1] & TEST_SAVE_RESTORE) {

				fprintf(stderr, "GUEST_SYNC #%d, save/restore VM state\n", iter);