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

David Hildenbrand
2019-11-12T12:09:39Z

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 */
> diff --git a/s390x/cstart64.S b/s390x/cstart64.S
> index 4be20fc..86dd4c4 100644
> --- a/s390x/cstart64.S
> +++ b/s390x/cstart64.S
> @@ -126,13 +126,18 @@ memsetxc:
> .globl diag308_load_reset
> diag308_load_reset:
> SAVE_REGS
> - /* Save the first PSW word to the IPL PSW */
> + /* Backup current PSW mask, as we have to restore it on success */
> epsw %r0, %r1
> - st %r0, 0
> - /* Store the address and the bit for 31 bit addressing */
> - larl %r0, 0f
> - oilh %r0, 0x8000
> - st %r0, 0x4
> + st %r0, GEN_LC_SW_INT_PSW
> + st %r1, GEN_LC_SW_INT_PSW + 4
> + /* Load reset psw mask (short psw, 64 bit) */
> + lg %r0, reset_psw
> + /* Load the success label address */
> + larl %r1, 0f
> + /* Or it to the mask */
> + ogr %r0, %r1
> + /* Store it at the reset PSW location (real 0x0) */
> + stg %r0, 0
> /* Do the reset */
> diag %r0,%r2,0x308
> /* Failure path */
> @@ -144,7 +149,10 @@ diag308_load_reset:
> lctlg %c0, %c0, 0(%r1)
> RESTORE_REGS
> lhi %r2, 1
> - br %r14
> + larl %r0, 1f
> + stg %r0, GEN_LC_SW_INT_PSW + 8
> + lpswe GEN_LC_SW_INT_PSW
> +1: br %r14
>
> .globl smp_cpu_setup_state
> smp_cpu_setup_state:
> @@ -184,6 +192,8 @@ svc_int:
> lpswe GEN_LC_SVC_OLD_PSW
>
> .align 8
> +reset_psw:
> + .quad 0x0008000180000000
> initial_psw:
> .quad 0x0000000180000000, clear_bss_start
> pgm_int_psw:
>

This patch breaks the smp test under TCG (no clue and no time to look
into the details :) ):

timeout -k 1s --foreground 90s
/home/dhildenb/git/qemu/s390x-softmmu/qemu-system-s390x -nodefaults
-nographic -machine s390-ccw-virtio,accel=tcg -chardev stdio,id=con0
-device sclpconsole,chardev=con0 -kernel s390x/smp.elf -smp 1 -smp 2 #
-initrd /tmp/tmp.EDi4y0tv58
SMP: Initializing, found 2 cpus
PASS: smp: start
PASS: smp: stop
FAIL: smp: stop store status: prefix
PASS: smp: stop store status: stack
PASS: smp: store status at address: running: incorrect state
PASS: smp: store status at address: running: status not written
PASS: smp: store status at address: stopped: status written
PASS: smp: ecall: ecall
PASS: smp: emcall: ecall
PASS: smp: cpu reset: cpu stopped
PASS: smp: reset initial: clear: psw
PASS: smp: reset initial: clear: prefix
PASS: smp: reset initial: clear: fpc
PASS: smp: reset initial: clear: cpu timer
PASS: smp: reset initial: clear: todpr
PASS: smp: reset initial: initialized: cr0 == 0xE0
PASS: smp: reset initial: initialized: cr14 == 0xC2000000
PASS: smp: reset initial: cpu stopped
SUMMARY: 18 tests, 1 unexpected failures

--

Thanks,

David / dhildenb