Re: [PATCH 19/24] bsd-user/arm/target_arch_signal.h: arm user context and trapframe for signals

[Richard Henderson]

On 10/19/21 9:44 AM, Warner Losh wrote:
> Arm specific user context structures for signal handling and the closely
> related trap frame.
>
> Signed-off-by: Stacey Son <sson@FreeBSD.org>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
> ---
>   bsd-user/arm/target_arch_signal.h | 38 +++++++++++++++++++++++++++++++
>   1 file changed, 38 insertions(+)
>
> diff --git a/bsd-user/arm/target_arch_signal.h 
> b/bsd-user/arm/target_arch_signal.h
> index 9fee58ca9c..67355ff28f 100644
> --- a/bsd-user/arm/target_arch_signal.h
> +++ b/bsd-user/arm/target_arch_signal.h
> @@ -90,4 +90,42 @@ typedef struct target_mcontext {
>       } __fpu;
>   } target_mcontext_t;
>   
> +typedef struct target_ucontext {
> +    target_sigset_t     uc_sigmask;
> +    target_mcontext_t   uc_mcontext;
> +    abi_ulong           uc_link;
> +    target_stack_t      uc_stack;
> +    int32_t             uc_flags;
> +    int32_t             __spare__[4];
> +} target_ucontext_t;

This is from the common <sys/_ucontext.h>.  Is there any way we can share that here in 
qemu as well?

> +struct target_sigframe {
> +    target_siginfo_t    sf_si;  /* saved siginfo */
> +    target_ucontext_t   sf_uc;  /* saved ucontext */
> +};

You're missing the storage for

  mcontext_vfp_t  sf_vfp

the address of which goes in mcontext_t.mc_vfp_ptr (which isn't in the version of 
mcontext_t from patch 18).

> +/* compare to sys/arm/include/frame.h */
> +struct target_trapframe {
> +    abi_ulong tf_spsr; /* Zero on arm26 */
> +    abi_ulong tf_r0;
> +    abi_ulong tf_r1;
> +    abi_ulong tf_r2;
> +    abi_ulong tf_r3;
> +    abi_ulong tf_r4;
> +    abi_ulong tf_r5;
> +    abi_ulong tf_r6;
> +    abi_ulong tf_r7;
> +    abi_ulong tf_r8;
> +    abi_ulong tf_r9;
> +    abi_ulong tf_r10;
> +    abi_ulong tf_r11;
> +    abi_ulong tf_r12;
> +    abi_ulong tf_usr_sp;
> +    abi_ulong tf_usr_lr;
> +    abi_ulong tf_svc_sp; /* Not used on arm26 */
> +    abi_ulong tf_svc_lr; /* Not used on arm26 */
> +    abi_ulong tf_pc;
> +};

This is not used by the user abi for signals.  It is a kernel structure for its own 
internal trap handling.  Why are you including it?


r~