On s390x, we can neither exit via PIO nor MMIO, but have to use an instruction like DIAGNOSE. Now that ucall() is implemented, we can use it in the sync_reg_test on s390x, too.
Reviewed-by: Andrew Jones drjones@redhat.com Signed-off-by: Thomas Huth thuth@redhat.com --- tools/testing/selftests/kvm/Makefile | 2 +- tools/testing/selftests/kvm/lib/s390x/ucall.c | 56 +++++++++++++++++++ .../selftests/kvm/s390x/sync_regs_test.c | 6 +- 3 files changed, 61 insertions(+), 3 deletions(-) create mode 100644 tools/testing/selftests/kvm/lib/s390x/ucall.c
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index a51e3b83df40..75ea1ecbf85a 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -10,7 +10,7 @@ UNAME_M := $(shell uname -m) LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/sparsebit.c LIBKVM_x86_64 = lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/ucall.c LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c -LIBKVM_s390x = lib/s390x/processor.c +LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c
TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test diff --git a/tools/testing/selftests/kvm/lib/s390x/ucall.c b/tools/testing/selftests/kvm/lib/s390x/ucall.c new file mode 100644 index 000000000000..fd589dc9bfab --- /dev/null +++ b/tools/testing/selftests/kvm/lib/s390x/ucall.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ucall support. A ucall is a "hypercall to userspace". + * + * Copyright (C) 2019 Red Hat, Inc. + */ +#include "kvm_util.h" + +void ucall_init(struct kvm_vm *vm, void *arg) +{ +} + +void ucall_uninit(struct kvm_vm *vm) +{ +} + +void ucall(uint64_t cmd, int nargs, ...) +{ + struct ucall uc = { + .cmd = cmd, + }; + va_list va; + int i; + + nargs = nargs <= UCALL_MAX_ARGS ? nargs : UCALL_MAX_ARGS; + + va_start(va, nargs); + for (i = 0; i < nargs; ++i) + uc.args[i] = va_arg(va, uint64_t); + va_end(va); + + /* Exit via DIAGNOSE 0x501 (normally used for breakpoints) */ + asm volatile ("diag 0,%0,0x501" : : "a"(&uc) : "memory"); +} + +uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc) +{ + struct kvm_run *run = vcpu_state(vm, vcpu_id); + struct ucall ucall = {}; + + if (run->exit_reason == KVM_EXIT_S390_SIEIC && + run->s390_sieic.icptcode == 4 && + (run->s390_sieic.ipa >> 8) == 0x83 && /* 0x83 means DIAGNOSE */ + (run->s390_sieic.ipb >> 16) == 0x501) { + int reg = run->s390_sieic.ipa & 0xf; + + memcpy(&ucall, addr_gva2hva(vm, run->s.regs.gprs[reg]), + sizeof(ucall)); + + vcpu_run_complete_io(vm, vcpu_id); + if (uc) + memcpy(uc, &ucall, sizeof(ucall)); + } + + return ucall.cmd; +} diff --git a/tools/testing/selftests/kvm/s390x/sync_regs_test.c b/tools/testing/selftests/kvm/s390x/sync_regs_test.c index e85ff0d69548..bbc93094519b 100644 --- a/tools/testing/selftests/kvm/s390x/sync_regs_test.c +++ b/tools/testing/selftests/kvm/s390x/sync_regs_test.c @@ -25,9 +25,11 @@
static void guest_code(void) { + register u64 stage asm("11") = 0; + for (;;) { - asm volatile ("diag 0,0,0x501"); - asm volatile ("ahi 11,1"); + GUEST_SYNC(0); + asm volatile ("ahi %0,1" : : "r"(stage)); } }