Re: [PATCH v2 05/10] s390x: smp: Loop if secondary cpu returns into cpu setup again

David Hildenbrand
2020-04-24T10:08:09Z

On 23.04.20 11:10, Janosch Frank wrote:
> Up to now a secondary cpu could have returned from the function it was
> executing and ending up somewhere in cstart64.S. This was mostly
> circumvented by an endless loop in the function that it executed.
>
> Let's add a loop to the end of the cpu setup, so we don't have to rely
> on added loops in the tests.
>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> Reviewed-by: Cornelia Huck <cohuck@redhat.com>
> ---
> s390x/cstart64.S | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/s390x/cstart64.S b/s390x/cstart64.S
> index 9af6bb3..ecffbe0 100644
> --- a/s390x/cstart64.S
> +++ b/s390x/cstart64.S
> @@ -161,7 +161,9 @@ smp_cpu_setup_state:
> lctlg %c0, %c0, GEN_LC_SW_INT_CRS
> /* We should only go once through cpu setup and not for every restart */
> stg %r14, GEN_LC_RESTART_NEW_PSW + 8
> - br %r14
> + brasl %r14, %r14
> + /* If the function returns, just loop here */
> +0: j 0
>
> pgm_int:
> SAVE_REGS
>

Reviewed-by: David Hildenbrand <david@redhat.com>

--
Thanks,

David / dhildenb