Re: [kvm-unit-tests PATCH v2 3/3] s390x: Load reset psw on diag308 reset

Janosch Frank
2019-11-13T10:04:59Z

[-- Attachment #1.1: Type: text/plain, Size: 3090 bytes --]

On 11/12/19 5:17 PM, Thomas Huth wrote:
> On 12/11/2019 14.42, Janosch Frank wrote:
>> On 11/12/19 1:09 PM, David Hildenbrand wrote:
>>> On 11.11.19 16:33, Janosch Frank wrote:
>>>> On a diag308 subcode 0 CRs will be reset, so we need a PSW mask
>>>> without DAT. Also we need to set the short psw indication to be
>>>> compliant with the architecture.
>>>>
>>>> Let's therefore define a reset PSW mask with 64 bit addressing and
>>>> short PSW indication that is compliant with architecture and use it.
>>>>
>>>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>>>> ---
>>>> lib/s390x/asm-offsets.c | 1 +
>>>> lib/s390x/asm/arch_def.h | 3 ++-
>>>> s390x/cstart64.S | 24 +++++++++++++++++-------
>>>> 3 files changed, 20 insertions(+), 8 deletions(-)
>>>>
>>>> diff --git a/lib/s390x/asm-offsets.c b/lib/s390x/asm-offsets.c
>>>> index 4b213f8..61d2658 100644
>>>> --- a/lib/s390x/asm-offsets.c
>>>> +++ b/lib/s390x/asm-offsets.c
>>>> @@ -58,6 +58,7 @@ int main(void)
>>>> OFFSET(GEN_LC_SW_INT_FPRS, lowcore, sw_int_fprs);
>>>> OFFSET(GEN_LC_SW_INT_FPC, lowcore, sw_int_fpc);
>>>> OFFSET(GEN_LC_SW_INT_CRS, lowcore, sw_int_crs);
>>>> + OFFSET(GEN_LC_SW_INT_PSW, lowcore, sw_int_psw);
>>>> OFFSET(GEN_LC_MCCK_EXT_SA_ADDR, lowcore, mcck_ext_sa_addr);
>>>> OFFSET(GEN_LC_FPRS_SA, lowcore, fprs_sa);
>>>> OFFSET(GEN_LC_GRS_SA, lowcore, grs_sa);
>>>> diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
>>>> index 07d4e5e..7d25e4f 100644
>>>> --- a/lib/s390x/asm/arch_def.h
>>>> +++ b/lib/s390x/asm/arch_def.h
>>>> @@ -79,7 +79,8 @@ struct lowcore {
>>>> uint32_t sw_int_fpc; /* 0x0300 */
>>>> uint8_t pad_0x0304[0x0308 - 0x0304]; /* 0x0304 */
>>>> uint64_t sw_int_crs[16]; /* 0x0308 */
>>>> - uint8_t pad_0x0310[0x11b0 - 0x0388]; /* 0x0388 */
>>>> + struct psw sw_int_psw; /* 0x0388 */
>>>> + uint8_t pad_0x0310[0x11b0 - 0x0390]; /* 0x0390 */
>>>> uint64_t mcck_ext_sa_addr; /* 0x11b0 */
>>>> uint8_t pad_0x11b8[0x1200 - 0x11b8]; /* 0x11b8 */
>>>> uint64_t fprs_sa[16]; /* 0x1200 */
> [...]
>>> This patch breaks the smp test under TCG (no clue and no time to look
>>> into the details :) ):
>>
>> I forgot to fixup the offset calculation at the top of the patch once
>> again...
>
> Maybe add a
>
> _Static_assert(sizeof(struct lowcore) == xyz)
>
> after the struct definitions, to avoid that this happens again?
>
> Thomas
>

How about this?
Or do we want to extend the struct to 8K and test for that?

diff --git i/lib/s390x/asm/arch_def.h w/lib/s390x/asm/arch_def.h
index 5f034a7..cf6e1ca 100644
--- i/lib/s390x/asm/arch_def.h
+++ w/lib/s390x/asm/arch_def.h
@@ -99,6 +99,7 @@ struct lowcore {
uint8_t pad_0x1400[0x1800 - 0x1400]; /* 0x1400 */
uint8_t pgm_int_tdb[0x1900 - 0x1800]; /* 0x1800 */
} __attribute__ ((__packed__));
+_Static_assert(sizeof(struct lowcore) == 0x1900, "Lowcore size");

#define PGM_INT_CODE_OPERATION 0x01
#define PGM_INT_CODE_PRIVILEGED_OPERATION 0x02

[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 833 bytes --]