On 5/25/21 7:37 PM, Claudio Imbrenda wrote:
> On Thu, 20 May 2021 09:47:30 +0000
> Janosch Frank <frankja@xxxxxxxxxxxxx> wrote:
>
>> Let's also check the PEI values to make sure our VSIE implementation
>> is correct.
>>
>> Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
>> ---
>> s390x/Makefile | 3 +-
>> s390x/mvpg-sie.c | 139
>> ++++++++++++++++++++++++++++++++ s390x/snippets/c/mvpg-snippet.c |
>> 33 ++++++++ s390x/unittests.cfg | 3 +
>> 4 files changed, 177 insertions(+), 1 deletion(-)
>> create mode 100644 s390x/mvpg-sie.c
>> create mode 100644 s390x/snippets/c/mvpg-snippet.c
>>
>> diff --git a/s390x/Makefile b/s390x/Makefile
>> index fe267011..6692cf73 100644
>> --- a/s390x/Makefile
>> +++ b/s390x/Makefile
>> @@ -22,6 +22,7 @@ tests += $(TEST_DIR)/uv-guest.elf
>> tests += $(TEST_DIR)/sie.elf
>> tests += $(TEST_DIR)/mvpg.elf
>> tests += $(TEST_DIR)/uv-host.elf
>> +tests += $(TEST_DIR)/mvpg-sie.elf
>>
>> tests_binary = $(patsubst %.elf,%.bin,$(tests))
>> ifneq ($(HOST_KEY_DOCUMENT),)
>> @@ -79,7 +80,7 @@ FLATLIBS = $(libcflat)
>> SNIPPET_DIR = $(TEST_DIR)/snippets
>>
>> # C snippets that need to be linked
>> -snippets-c =
>> +snippets-c = $(SNIPPET_DIR)/c/mvpg-snippet.gbin
>>
>> # ASM snippets that are directly compiled and converted to a *.gbin
>> snippets-a =
>> diff --git a/s390x/mvpg-sie.c b/s390x/mvpg-sie.c
>> new file mode 100644
>> index 00000000..a617704b
>> --- /dev/null
>> +++ b/s390x/mvpg-sie.c
>> @@ -0,0 +1,139 @@
>> +#include <libcflat.h>
>> +#include <asm/asm-offsets.h>
>> +#include <asm-generic/barrier.h>
>> +#include <asm/interrupt.h>
>> +#include <asm/pgtable.h>
>> +#include <mmu.h>
>> +#include <asm/page.h>
>> +#include <asm/facility.h>
>> +#include <asm/mem.h>
>> +#include <asm/sigp.h>
>> +#include <smp.h>
>> +#include <alloc_page.h>
>> +#include <bitops.h>
>> +#include <vm.h>
>> +#include <sclp.h>
>> +#include <sie.h>
>> +
>> +static u8 *guest;
>> +static u8 *guest_instr;
>> +static struct vm vm;
>> +
>> +static uint8_t *src;
>> +static uint8_t *dst;
>> +
>> +extern const char _binary_s390x_snippets_c_mvpg_snippet_gbin_start[];
>> +extern const char _binary_s390x_snippets_c_mvpg_snippet_gbin_end[];
>> +int binary_size;
>> +
>> +static void handle_validity(struct vm *vm)
>> +{
>> + report(0, "VALIDITY: %x", vm->sblk->ipb >> 16);
>
> I think an assert would be better. This should not happen, and if it
> happens something went very wrong and we have no guarantee that we will
> be able to continue
That depends on the test. If you use multiple gbins/snippets in a test,
then a validity for one of those does not necessarily break the others.
Especially when you think about PV tests where the destroy will clean
out all the state anyway.
>
>> +}
>> +
>> +static void sie(struct vm *vm)
>> +{
>> + /* Reset icptcode so we don't trip below */
>> + vm->sblk->icptcode = 0;
>> +
>> + while (vm->sblk->icptcode == 0) {
>> + sie64a(vm->sblk, &vm->save_area);
>> + if (vm->sblk->icptcode == ICPT_VALIDITY)
>> + handle_validity(vm);
>> + }
>> + vm->save_area.guest.grs[14] = vm->sblk->gg14;
>> + vm->save_area.guest.grs[15] = vm->sblk->gg15;
>> +}
>> +
>> +static void test_mvpg_pei(void)
>> +{
>> + uint64_t **pei_dst = (uint64_t **)((uintptr_t) vm.sblk +
>> 0xc0);
>> + uint64_t **pei_src = (uint64_t **)((uintptr_t) vm.sblk +
>> 0xc8); +
>> + report_prefix_push("pei");
>
> maybe clear the destination buffer...
>
>> + protect_page(guest + 0x6000, PAGE_ENTRY_I);
>> + sie(&vm);
>> + report(vm.sblk->icptcode == ICPT_PARTEXEC, "Partial
>> execution");
>> + report((uintptr_t)**pei_src == ((uintptr_t)vm.sblk->mso) +
>> 0x6000 + PAGE_ENTRY_I, "PEI_SRC correct");
>> + report((uintptr_t)**pei_dst == vm.sblk->mso + 0x5000,
>> "PEI_DST correct");
>
> ... and check that the page was not copied
Sure
>
>> + /* Jump over the diag44 */
>> + sie(&vm);
>
> I would check if you really got a diag44
Sure, reporting doesn't make sense to me but an assert should be fine
>
>> + /* Clear PEI data for next check */
>> + memset((uint64_t *)((uintptr_t) vm.sblk + 0xc0), 0, 16);
>> + unprotect_page(guest + 0x6000, PAGE_ENTRY_I);
>> + protect_page(guest + 0x5000, PAGE_ENTRY_I);
>> + sie(&vm);
>> + report(vm.sblk->icptcode == ICPT_PARTEXEC, "Partial
>> execution");
>> + report((uintptr_t)**pei_src == vm.sblk->mso + 0x6000,
>> "PEI_SRC correct");
>> + report((uintptr_t)**pei_dst == vm.sblk->mso + 0x5000 +
>> PAGE_ENTRY_I, "PEI_DST correct"); +
>> + report_prefix_pop();
>> +}
>> +
>> +static void test_mvpg(void)
>> +{
>> + int binary_size =
>> ((uintptr_t)_binary_s390x_snippets_c_mvpg_snippet_gbin_end -
>> +
>> (uintptr_t)_binary_s390x_snippets_c_mvpg_snippet_gbin_start); +
>> + memcpy(guest,
>> _binary_s390x_snippets_c_mvpg_snippet_gbin_start, binary_size);
>> + memset(src, 0x42, PAGE_SIZE);
>> + memset(dst, 0x43, PAGE_SIZE);
>> + sie(&vm);
>> + mb();
>> + report(!memcmp(src, dst, PAGE_SIZE) && *dst == 0x42, "Page
>
> or maybe you can clear the destination buffer here, if you prefer
I'll have a look, thanks for the review!
>
>> moved"); +}
>> +
>> +static void setup_guest(void)
>> +{
>> + setup_vm();
>> +
>> + /* Allocate 1MB as guest memory */
>> + guest = alloc_pages(8);
>> + /* The first two pages are the lowcore */
>> + guest_instr = guest + PAGE_SIZE * 2;
>> +
>> + vm.sblk = alloc_page();
>> +
>> + vm.sblk->cpuflags = CPUSTAT_ZARCH | CPUSTAT_RUNNING;
>> + vm.sblk->prefix = 0;
>> + /*
>> + * Pageable guest with the same ASCE as the test programm,
>> but
>> + * the guest memory 0x0 is offset to start at the allocated
>> + * guest pages and end after 1MB.
>> + *
>> + * It's not pretty but faster and easier than managing guest
>> ASCEs.
>> + */
>> + vm.sblk->mso = (u64)guest;
>> + vm.sblk->msl = (u64)guest;
>> + vm.sblk->ihcpu = 0xffff;
>> +
>> + vm.sblk->crycbd = (uint64_t)alloc_page();
>> +
>> + vm.sblk->gpsw.addr = PAGE_SIZE * 4;
>> + vm.sblk->gpsw.mask = 0x0000000180000000ULL;
>> + vm.sblk->ictl = ICTL_OPEREXC | ICTL_PINT;
>> + /* Enable MVPG interpretation as we want to test KVM and not
>> ourselves */
>> + vm.sblk->eca = ECA_MVPGI;
>> +
>> + src = guest + PAGE_SIZE * 6;
>> + dst = guest + PAGE_SIZE * 5;
>> +}
>> +
>> +int main(void)
>> +{
>> + report_prefix_push("mvpg-sie");
>> + if (!sclp_facilities.has_sief2) {
>> + report_skip("SIEF2 facility unavailable");
>> + goto done;
>> + }
>> +
>> + setup_guest();
>> + test_mvpg();
>> + test_mvpg_pei();
>> +
>> +done:
>> + report_prefix_pop();
>> + return report_summary();
>> +
>> +}
>> diff --git a/s390x/snippets/c/mvpg-snippet.c
>> b/s390x/snippets/c/mvpg-snippet.c new file mode 100644
>> index 00000000..96b70c9c
>> --- /dev/null
>> +++ b/s390x/snippets/c/mvpg-snippet.c
>> @@ -0,0 +1,33 @@
>> +#include <libcflat.h>
>> +
>> +static inline void force_exit(void)
>> +{
>> + asm volatile(" diag 0,0,0x44\n");
>> +}
>> +
>> +static inline int mvpg(unsigned long r0, void *dest, void *src)
>> +{
>> + register unsigned long reg0 asm ("0") = r0;
>> + int cc;
>> +
>> + asm volatile(" mvpg %1,%2\n"
>> + " ipm %0\n"
>> + " srl %0,28"
>> + : "=&d" (cc) : "a" (dest), "a" (src), "d" (reg0)
>> + : "memory", "cc");
>> + return cc;
>> +}
>> +
>> +static void test_mvpg_real(void)
>> +{
>> + mvpg(0, (void *)0x5000, (void *)0x6000);
>> + force_exit();
>> +}
>> +
>> +__attribute__((section(".text"))) int main(void)
>> +{
>> + test_mvpg_real();
>> + test_mvpg_real();
>> + test_mvpg_real();
>> + return 0;
>> +}
>> diff --git a/s390x/unittests.cfg b/s390x/unittests.cfg
>> index 9f81a608..8634b1b1 100644
>> --- a/s390x/unittests.cfg
>> +++ b/s390x/unittests.cfg
>> @@ -103,3 +103,6 @@ file = sie.elf
>> [mvpg]
>> file = mvpg.elf
>> timeout = 10
>> +
>> +[mvpg-sie]
>> +file = mvpg-sie.elf
>
