Re: [PATCH 04/21] linux-user/arm: Implement setup_sigtramp

[Alex Bennée]

Richard Henderson <richard.henderson@linaro.org> writes:

> ARM is more complicated than the others, in that we also
> have trampolines for using SA_RESTORER with FDPIC, and
> we need to create trampolines for both ARM and Thumb modes.
>
> Cc: qemu-arm@nongnu.org
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  linux-user/arm/target_signal.h |   2 +
>  linux-user/arm/signal.c        | 170 +++++++++++++++++++--------------
>  2 files changed, 100 insertions(+), 72 deletions(-)
>
> +
> +    /* ARM sigframe */
> +    _Static_assert(SIGFRAME_FDPIC_OFS <= 0xfff);
> +    __put_user(0xe59d9000 | SIGFRAME_FDPIC_OFS, &tramp[i++]);
> +    __put_user(0xe8998200, &tramp[i++]);

Erm is this based on your c11 series?

> +
> +    /* Thumb sigframe */
> +    _Static_assert(SIGFRAME_FDPIC_OFS <= 0xff << 2);
> +    _Static_assert((SIGFRAME_FDPIC_OFS & 3) == 0);
> +    __put_user(0x9a00e9dd | (SIGFRAME_FDPIC_OFS << 14), &tramp[i++]);
> +    __put_user(0x46c04750, &tramp[i++]);
> +
> +    /* ARM rt_sigframe */
> +    _Static_assert(RT_SIGFRAME_FDPIC_OFS <= 0xfff);
> +    __put_user(0xe59d9000 | RT_SIGFRAME_FDPIC_OFS, &tramp[i++]);
> +    __put_user(0xe8998200, &tramp[i++]);
> +
> +    /* Thumb rt_sigframe */
> +    _Static_assert(RT_SIGFRAME_FDPIC_OFS <= 0xff << 2);
> +    _Static_assert((RT_SIGFRAME_FDPIC_OFS & 3) == 0);
> +    __put_user(0x9a00e9dd | (RT_SIGFRAME_FDPIC_OFS << 14), &tramp[i++]);
> +    __put_user(0x46c04750, &tramp[i++]);
> +
> +    unlock_user(tramp, sigtramp_page, total_size);
> +}

-- 
Alex Bennée