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charset="utf-8" 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: Paolo Bonzini --- tools/testing/selftests/kvm/x86/amx_test.c | 38 +++++++++++++++++----- 1 file changed, 30 insertions(+), 8 deletions(-) diff --git a/tools/testing/selftests/kvm/x86/amx_test.c b/tools/testing/sel= ftests/kvm/x86/amx_test.c index 4ac41c1a7255..00a42a592a37 100644 --- a/tools/testing/selftests/kvm/x86/amx_test.c +++ b/tools/testing/selftests/kvm/x86/amx_test.c @@ -125,11 +125,17 @@ static void set_tilecfg(struct tile_config *cfg) } =20 enum { + /* Retrieve TMM0 from guest, stash it for TEST_RESTORE_TILEDATA */ + TEST_SAVE_TILEDATA =3D 1, + /* Check TMM0 against tiledata */ - TEST_COMPARE_TILEDATA =3D 1, + TEST_COMPARE_TILEDATA =3D 2, + + /* Restore TMM0 from earlier save */ + TEST_RESTORE_TILEDATA =3D 4, =20 /* Full VM save/restore */ - TEST_SAVE_RESTORE =3D 2, + TEST_SAVE_RESTORE =3D 8, }; =20 static void __attribute__((__flatten__)) guest_code(struct tile_config *am= x_cfg, @@ -150,7 +156,16 @@ static void __attribute__((__flatten__)) guest_code(st= ruct 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=3D0x40000, 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 =3D NULL; int xsave_restore_size; vm_vaddr_t amx_cfg, tiledata, xstate; struct ucall uc; - u32 amx_offset; int ret; =20 /* @@ -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 =3D vcpu_save_state(vcpu); + } if (uc.args[1] & TEST_COMPARE_TILEDATA) { fprintf(stderr, "GUEST_SYNC #%d, check TMM0 contents\n", iter); =20 /* Compacted mode, get amx offset by xsave area * size subtract 8K amx size. */ - amx_offset =3D xsave_restore_size - NUM_TILES*TILE_SIZE; - state =3D vcpu_save_state(vcpu); - void *amx_start =3D (void *)state->xsave + amx_offset; + u32 amx_offset =3D xsave_restore_size - NUM_TILES*TILE_SIZE; + void *amx_start =3D (void *)tile_state->xsave + amx_offset; void *tiles_data =3D (void *)addr_gva2hva(vm, tiledata); /* Only check TMM0 register, 1 tile */ ret =3D memcmp(amx_start, tiles_data, TILE_SIZE); TEST_ASSERT(ret =3D=3D 0, "memcmp failed, ret=3D%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); --=20 2.52.0