target/s390x: Fix PPNO execution with icount

[PATCH] target/s390x: Fix PPNO execution with icount

Posted by Ilya Leoshkevich 2 months, 1 week ago

Executing PERFORM RANDOM NUMBER OPERATION makes QEMU exit with "Bad
icount read" when using record/replay. This is caused by
icount_get_raw_locked() if the current instruction is not the last one
in the respective translation block.

For the x86_64's rdrand this is resolved by calling
translator_io_start(). On s390x one uses IF_IO in order to make this
call happen automatically.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
 target/s390x/tcg/insn-data.h.inc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/s390x/tcg/insn-data.h.inc b/target/s390x/tcg/insn-data.h.inc
index e7d61cdec28..ec730ee0919 100644
--- a/target/s390x/tcg/insn-data.h.inc
+++ b/target/s390x/tcg/insn-data.h.inc
@@ -1012,7 +1012,7 @@
     D(0xb92e, KM,      RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KM)
     D(0xb92f, KMC,     RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KMC)
     D(0xb929, KMA,     RRF_b, MSA8, 0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KMA)
-    D(0xb93c, PPNO,    RRE,   MSA5, 0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_PPNO)
+    E(0xb93c, PPNO,    RRE,   MSA5, 0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_PPNO, IF_IO)
     D(0xb93e, KIMD,    RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KIMD)
     D(0xb93f, KLMD,    RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KLMD)
 
-- 
2.48.1

Re: [PATCH] target/s390x: Fix PPNO execution with icount

Posted by Richard Henderson 2 months, 1 week ago

On 1/23/25 04:37, Ilya Leoshkevich wrote:
> Executing PERFORM RANDOM NUMBER OPERATION makes QEMU exit with "Bad
> icount read" when using record/replay. This is caused by
> icount_get_raw_locked() if the current instruction is not the last one
> in the respective translation block.
> 
> For the x86_64's rdrand this is resolved by calling
> translator_io_start(). On s390x one uses IF_IO in order to make this
> call happen automatically.
> 
> Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
> ---
>   target/s390x/tcg/insn-data.h.inc | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/s390x/tcg/insn-data.h.inc b/target/s390x/tcg/insn-data.h.inc
> index e7d61cdec28..ec730ee0919 100644
> --- a/target/s390x/tcg/insn-data.h.inc
> +++ b/target/s390x/tcg/insn-data.h.inc
> @@ -1012,7 +1012,7 @@
>       D(0xb92e, KM,      RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KM)
>       D(0xb92f, KMC,     RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KMC)
>       D(0xb929, KMA,     RRF_b, MSA8, 0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KMA)
> -    D(0xb93c, PPNO,    RRE,   MSA5, 0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_PPNO)
> +    E(0xb93c, PPNO,    RRE,   MSA5, 0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_PPNO, IF_IO)
>       D(0xb93e, KIMD,    RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KIMD)
>       D(0xb93f, KLMD,    RRE,   MSA,  0, 0, 0, 0, msa, 0, S390_FEAT_TYPE_KLMD)
>   

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

r~