Re: [Qemu-devel] [PATCH 1/4] linux-user/s390x: Mask si_addr for SIGSEGV

[Laurent Vivier]

Le 06/11/2017 à 19:33, Peter Maydell a écrit :
> For s390x, the address passed to a signal handler in the
> siginfo_t si_addr field is masked (in the kernel this is done in
> do_sigbus() and do_sigsegv() in arch/s390/mm/fault.c). Implement
> this architecture-specific oddity in linux-user.
> 
> This is one of the issues described in
> https://bugs.launchpad.net/qemu/+bug/1705118
> 
> Signed-off-by: Peter Maydell <address@hidden>
> ---
>  linux-user/main.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/linux-user/main.c b/linux-user/main.c
> index aa02f25..b6dd9ef 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -3238,6 +3238,10 @@ void cpu_loop(CPUAlphaState *env)
>  #endif /* TARGET_ALPHA */
>  
>  #ifdef TARGET_S390X
> +
> +/* s390x masks the fault address it reports in si_addr for SIGSEGV and 
> SIGBUS */
> +#define S390X_FAIL_ADDR_MASK -4096LL
> +
>  void cpu_loop(CPUS390XState *env)
>  {
>      CPUState *cs = CPU(s390_env_get_cpu(env));
> @@ -3294,7 +3298,7 @@ void cpu_loop(CPUS390XState *env)
>                  sig = TARGET_SIGSEGV;
>                  /* XXX: check env->error_code */
>                  n = TARGET_SEGV_MAPERR;
> -                addr = env->__excp_addr;
> +                addr = env->__excp_addr & S390X_FAIL_ADDR_MASK;
>                  goto do_signal;
>              case PGM_EXECUTE:
>              case PGM_SPECIFICATION:
> 

Reviewed-by: Laurent Vivier <address@hidden>