On Thu, 12 May 2022 16:01:07 +0200 Nico Boehr <nrb@xxxxxxxxxxxxx> wrote: > Upon migration, we expect storage keys being set by the guest to be preserved, > so add a test for it. > > We keep 128 pages and set predictable storage keys. Then, we migrate and check > they can be read back and the respective access restrictions are in place when > the access key in the PSW doesn't match. > > TCG currently doesn't implement key-controlled protection, see > target/s390x/mmu_helper.c, function mmu_handle_skey(), hence add the relevant > tests as xfails. > > Signed-off-by: Nico Boehr <nrb@xxxxxxxxxxxxx> > --- > s390x/Makefile | 1 + > s390x/migration-skey.c | 98 ++++++++++++++++++++++++++++++++++++++++++ > s390x/unittests.cfg | 4 ++ > 3 files changed, 103 insertions(+) > create mode 100644 s390x/migration-skey.c > > diff --git a/s390x/Makefile b/s390x/Makefile > index a8e04aa6fe4d..f8ea594b641d 100644 > --- a/s390x/Makefile > +++ b/s390x/Makefile > @@ -32,6 +32,7 @@ tests += $(TEST_DIR)/epsw.elf > tests += $(TEST_DIR)/adtl-status.elf > tests += $(TEST_DIR)/migration.elf > tests += $(TEST_DIR)/pv-attest.elf > +tests += $(TEST_DIR)/migration-skey.elf > > pv-tests += $(TEST_DIR)/pv-diags.elf > > diff --git a/s390x/migration-skey.c b/s390x/migration-skey.c > new file mode 100644 > index 000000000000..6f3053d8ab40 > --- /dev/null > +++ b/s390x/migration-skey.c > @@ -0,0 +1,98 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Storage Key migration tests > + * > + * Copyright IBM Corp. 2022 > + * > + * Authors: > + * Nico Boehr <nrb@xxxxxxxxxxxxx> > + */ > + > +#include <libcflat.h> > +#include <asm/facility.h> > +#include <asm/page.h> > +#include <asm/mem.h> > +#include <asm/interrupt.h> > +#include <hardware.h> > + > +#define NUM_PAGES 128 > +static uint8_t pagebuf[NUM_PAGES][PAGE_SIZE] __attribute__((aligned(PAGE_SIZE))); > + > +static void test_migration(void) > +{ > + int i, key_to_set; > + uint8_t *page; > + union skey expected_key, actual_key, mismatching_key; > + > + for (i = 0; i < NUM_PAGES; i++) { > + /* > + * Storage keys are 7 bit, lowest bit is always returned as zero > + * by iske > + */ > + key_to_set = i * 2; > + set_storage_key(pagebuf + i, key_to_set, 1); > + } > + > + puts("Please migrate me, then press return\n"); > + (void)getchar(); > + > + for (i = 0; i < NUM_PAGES; i++) { > + report_prefix_pushf("page %d", i); > + > + page = &pagebuf[i][0]; > + actual_key.val = get_storage_key(page); > + expected_key.val = i * 2; > + > + /* ignore reference bit */ > + actual_key.str.rf = 0; > + expected_key.str.rf = 0; > + > + report(actual_key.val == expected_key.val, "expected_key=0x%x actual_key=0x%x", expected_key.val, actual_key.val); > + > + /* ensure access key doesn't match storage key and is never zero */ > + mismatching_key.str.acc = expected_key.str.acc < 15 ? expected_key.str.acc + 1 : 1; mismatching_key.str.acc = (expected_key.str.acc ^ 2) | 1; > + *page = 0xff; > + > + expect_pgm_int(); > + asm volatile ( > + /* set access key */ > + "spka 0(%[mismatching_key])\n" > + /* try to write page */ > + "mvi 0(%[page]), 42\n" > + /* reset access key */ > + "spka 0\n" > + : > + : [mismatching_key] "a"(mismatching_key.val), > + [page] "a"(page) > + : "memory" > + ); > + check_pgm_int_code_xfail(host_is_tcg(), PGM_INT_CODE_PROTECTION); > + report_xfail(host_is_tcg(), *page == 0xff, "no store occured"); > + > + report_prefix_pop(); > + } > +} > + > +int main(void) > +{ > + report_prefix_push("migration-skey"); > + if (test_facility(169)) { > + report_skip("storage key removal facility is active"); > + > + /* > + * If we just exit and don't ask migrate_cmd to migrate us, it > + * will just hang forever. Hence, also ask for migration when we > + * skip this test alltogether. > + */ > + puts("Please migrate me, then press return\n"); > + (void)getchar(); > + > + goto done; > + } > + > + test_migration(); > + > +done: > + report_prefix_pop(); > + return report_summary(); > +} > diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg > index b456b2881448..1e851d8e3dd8 100644 > --- a/s390x/unittests.cfg > +++ b/s390x/unittests.cfg > @@ -176,3 +176,7 @@ extra_params = -cpu qemu,gs=off,vx=off > file = migration.elf > groups = migration > smp = 2 > + > +[migration-skey] > +file = migration-skey.elf > +groups = migration