Regression test for the bug where ESSA emulation in migration mode silently dropped addressing exceptions instead of injecting PGM_ADDRESSING into the guest.
The test is integrated into cmma_test alongside the existing CMMA migration tests. Signed-off-by: Gautam Gala <[email protected]> --- .../selftests/kvm/include/s390/processor.h | 7 ++ tools/testing/selftests/kvm/s390/cmma_test.c | 69 +++++++++++++++++++ 2 files changed, 76 insertions(+) diff --git a/tools/testing/selftests/kvm/include/s390/processor.h b/tools/testing/selftests/kvm/include/s390/processor.h index 33fef6fd9617..d71df6784dad 100644 --- a/tools/testing/selftests/kvm/include/s390/processor.h +++ b/tools/testing/selftests/kvm/include/s390/processor.h @@ -26,6 +26,13 @@ #define PAGE_SIZE BIT_ULL(PAGE_SHIFT) #define PAGE_MASK (~(PAGE_SIZE - 1)) +/* Program interruption codes */ +#define PGM_ADDRESSING 0x05 + +/* Lowcore offsets */ +#define __LC_PGM_INT_CODE 0x8e +#define __LC_PGM_NEW_PSW 0x1d0 + /* Is there a portable way to do this? */ static inline void cpu_relax(void) { diff --git a/tools/testing/selftests/kvm/s390/cmma_test.c b/tools/testing/selftests/kvm/s390/cmma_test.c index 15d81b2ed7ad..0899fa971dcb 100644 --- a/tools/testing/selftests/kvm/s390/cmma_test.c +++ b/tools/testing/selftests/kvm/s390/cmma_test.c @@ -18,6 +18,9 @@ #include "kselftest.h" #include "ucall_common.h" #include "processor.h" +#include "sie.h" + +#define UNMAPPED_GFN 0xffff000UL #define MAIN_PAGE_COUNT 512 @@ -651,6 +654,71 @@ static void test_get_skip_holes(void) assert_no_pages_cmma_dirty(vm); } +static void pgm_handler_c(void) +{ + uint16_t pgm_code; + + memcpy(&pgm_code, (void *)__LC_PGM_INT_CODE, sizeof(pgm_code)); + GUEST_SYNC(pgm_code); + for (;;) + ; +} + +static void guest_essa_unmapped(void) +{ + unsigned long addr = UNMAPPED_GFN << PAGE_SHIFT; + + asm volatile( + " lg 2,%[addr]\n" + /* ESSA r1,r2,orc=1 */ + " .insn rrf,0xb9ab0000,1,2,1,0\n" + : + : [addr] "Q"(addr) + : "r1", "r2", "cc", "memory" + ); + + GUEST_SYNC(0); +} + +static void test_essa_migration_pgm(void) +{ + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + struct ucall uc; + char *lowcore; + u64 pgm_psw[2] = {}; + + vm = __vm_create(VM_SHAPE_DEFAULT, 1, 0); + + enable_cmma(vm); + + vcpu = vm_vcpu_add(vm, 0, guest_essa_unmapped); + + /* The guest runs with DAT on; map the lowcore so the handler can read it. */ + virt_map(vm, 0, 0, 1); + + lowcore = addr_gpa2hva(vm, 0); + pgm_psw[0] = vcpu->run->psw_mask; + pgm_psw[1] = (u64)pgm_handler_c; + memcpy(lowcore + __LC_PGM_NEW_PSW, pgm_psw, 16); + + vm_mem_region_set_flags(vm, 0, KVM_MEM_LOG_DIRTY_PAGES); + enable_migration_mode(vm); + + vcpu_run(vcpu); + + TEST_ASSERT_EQ(vcpu->run->exit_reason, KVM_EXIT_S390_SIEIC); + TEST_ASSERT_EQ(vcpu->run->s390_sieic.icptcode, ICPT_INST); + TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipa & 0xff00, 0x8300); /* DIAG */ + TEST_ASSERT_EQ(vcpu->run->s390_sieic.ipb >> 16, 0x501); + + get_ucall(vcpu, &uc); + TEST_ASSERT_EQ(uc.cmd, UCALL_SYNC); + TEST_ASSERT_EQ(uc.args[1], PGM_ADDRESSING); + + kvm_vm_free(vm); +} + struct testdef { const char *name; void (*test)(void); @@ -659,6 +727,7 @@ struct testdef { { "GET_CMMA_BITS: basic calls", test_get_cmma_basic }, { "GET_CMMA_BITS: all pages are dirty initially", test_get_initial_dirty }, { "GET_CMMA_BITS: holes are skipped", test_get_skip_holes }, + { "ESSA migration mode: PGM_ADDRESSING injected on unmapped GFN", test_essa_migration_pgm }, }; /** -- 2.55.0
