Re: [PATCH] target/hppa: mask upper iaoq bits when returning to narrow mode

[Richard Henderson <richard.henderson@linaro.org>]

On 4/1/24 04:52, Sven Schnelle wrote:
> For unknown reasons, Java 1.5 on 64-bit HP-UX 11.11 does signed
> computation of the new IAOQ value in the signal handler. In the
> current code these bits are not masked when returning to narrow
> mode, causing java to crash.
> 
> Signed-off-by: Sven Schnelle <svens@stackframe.org>
> ---
>   target/hppa/sys_helper.c | 4 ++++
>   1 file changed, 4 insertions(+)
> 
> diff --git a/target/hppa/sys_helper.c b/target/hppa/sys_helper.c
> index 208e51c086..3bbc2da71b 100644
> --- a/target/hppa/sys_helper.c
> +++ b/target/hppa/sys_helper.c
> @@ -83,6 +83,10 @@ void HELPER(rfi)(CPUHPPAState *env)
>       env->iaoq_f = env->cr[CR_IIAOQ];
>       env->iaoq_b = env->cr_back[1];
>   
> +    if (!(env->cr[CR_IPSW] & PSW_W)) {
> +        env->iaoq_f &= 0xffffffff;
> +        env->iaoq_b &= 0xffffffff;
> +    }

This shouldn't be needed, because we are already masking these bits later, in 
cpu_get_tb_cpu_state.  But I do have some cleanups in this area, and perhaps one of them 
matters.


Please try

https://gitlab.com/rth7680/qemu/-/commit/d06e0303595a63565593ab2a5d42f312135b9ded


r~