On 22 March 2018 at 21:58, Laurent Vivier <laur...@vivier.eu> wrote:
> Signed-off-by: Laurent Vivier <laur...@vivier.eu>
> ---
> linux-user/signal.c | 9 ++-------
> 1 file changed, 2 insertions(+), 7 deletions(-)
>
> diff --git a/linux-user/signal.c b/linux-user/signal.c
> index 2c08ca14cf..514145b299 100644
> --- a/linux-user/signal.c
> +++ b/linux-user/signal.c
> @@ -253,17 +253,15 @@ int do_sigprocmask(int how, const sigset_t *set,
> sigset_t *oldset)
> return 0;
> }
>
> -#if !defined(TARGET_OPENRISC) && !defined(TARGET_NIOS2)
> /* Just set the guest's signal mask to the specified value; the
> * caller is assumed to have called block_signals() already.
> */
> -static void set_sigmask(const sigset_t *set)
> +static __attribute__((unused)) void set_sigmask(const sigset_t *set)
> {
> TaskState *ts = (TaskState *)thread_cpu->opaque;
>
> ts->signal_mask = *set;
> }
> -#endif
>
> /* siginfo conversion */
>
> @@ -533,8 +531,7 @@ static void force_sig(int sig)
> * up the signal frame. oldsig is the signal we were trying to handle
> * at the point of failure.
> */
> -#if !defined(TARGET_RISCV)
> -static void force_sigsegv(int oldsig)
> +static __attribute__((unused)) void force_sigsegv(int oldsig)
> {
> if (oldsig == SIGSEGV) {
> /* Make sure we don't try to deliver the signal again; this will
> @@ -545,8 +542,6 @@ static void force_sigsegv(int oldsig)
> force_sig(TARGET_SIGSEGV);
> }
>
> -#endif
> -
> /* abort execution with signal */
> static void QEMU_NORETURN dump_core_and_abort(int target_sig)
> {
I don't think this is the right approach. In both of these
cases, the fact that the function is unused is a red flag that
there is a bug in the signal emulation code for those guest CPUs.
If the guest CPU code isn't calling set_sigmask() it is failing
to correctly handle the sigmask field in the ucontext on
signal return, and if it's not calling force_sigsegv() then
it's doing something wrong with the handling of "we couldn't
write to the signal frame" on signal entry.
I think it's worth keeping the #ifdef as a flag and
a list of what targets we need to fix.
(The "riscv isn't using force_sigsegv()" fix looks like it should be
trivial -- their setup_rt_frame() has the code path but it's
incorrectly trying to do this by hand rather than calling
force_sigsegv().)
thanks
-- PMM
