Re: [PATCH for-5.2 3/3] linux-user/sparc: Don't zero high half of PC, NPC, PSR in sigreturn

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

On 11/5/20 1:23 PM, Peter Maydell wrote:
> The function do_sigreturn() tries to store the PC, NPC and PSR in
> uint32_t local variables, which implicitly drops the high half of
> these fields for 64-bit guests.
> 
> The usual effect was that a guest which used signals would crash on
> return from a signal unless it was lucky enough to take it while the
> PC was in the low 4GB of the address space.  In particular, Debian
> /bin/dash and /bin/bash would segfault after executing external
> commands.
> 
> Use abi_ulong, which is the type these fields all have in the
> __siginfo_t struct.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  linux-user/sparc/signal.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

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

r~