On Fri, 2021-05-21 at 09:54 +0200, David Hildenbrand wrote:
> On 21.05.21 05:01, Ilya Leoshkevich wrote:
> > Verify that s390x-specific uc_mcontext.psw.addr is reported
> > correctly.
> >
> > Signed-off-by: Ilya Leoshkevich <i...@linux.ibm.com>
> > ---
> > tests/tcg/s390x/Makefile.target | 1 +
> > tests/tcg/s390x/sigill.c | 41
> > +++++++++++++++++++++++++++++++++
> > 2 files changed, 42 insertions(+)
> > create mode 100644 tests/tcg/s390x/sigill.c
> >
> > diff --git a/tests/tcg/s390x/Makefile.target
> > b/tests/tcg/s390x/Makefile.target
> > index 241ef28f61..8699d829a5 100644
> > --- a/tests/tcg/s390x/Makefile.target
> > +++ b/tests/tcg/s390x/Makefile.target
> > @@ -8,3 +8,4 @@ TESTS+=exrl-trtr
> > TESTS+=pack
> > TESTS+=mvo
> > TESTS+=mvc
> > +TESTS+=sigill
> > diff --git a/tests/tcg/s390x/sigill.c b/tests/tcg/s390x/sigill.c
> > new file mode 100644
> > index 0000000000..f8021dc6af
> > --- /dev/null
> > +++ b/tests/tcg/s390x/sigill.c
> > @@ -0,0 +1,41 @@
> > +#include <assert.h>
> > +#include <signal.h>
> > +#include <string.h>
> > +#include <ucontext.h>
> > +#include <unistd.h>
> > +
> > +extern char expected_si_addr[];
> > +extern char expected_psw_addr[];
>
> Why "extern" ? For the magic inline asm below to work?
Yes - it cannot be static, because AFAIK there is no such thing as
static variable declaration (one can only define static variables).
> > +
> > +static void handle_signal(int sig, siginfo_t *info, void
> > *ucontext)
> > +{
> > + if (sig != SIGILL) {
> > + _exit(1);
> > + }
> > +
> > + if (info->si_addr != expected_si_addr) {
> > + _exit(2);
> > + }
> > +
> > + if (((ucontext_t *)ucontext)->uc_mcontext.psw.addr !=
> > + (unsigned long)expected_psw_addr) {
> > + _exit(3);
> > + }
> > +}
> > +
> > +int main(void)
> > +{
> > + struct sigaction act;
> > +
> > + memset(&act, 0, sizeof(act));
> > + act.sa_sigaction = handle_signal;
> > + act.sa_flags = SA_SIGINFO;
> > +
> > + int ret = sigaction(SIGILL, &act, NULL);
>
> Mixing code and declaration.
Ouch, will fix.
> > + assert(ret == 0);
> > +
> > + asm volatile("expected_si_addr:\t.byte\t0x00,0x00\n"
> > + "expected_psw_addr:");
>
> At least I am confused how the right values actually end up in
> expected_si_addr and expected_psw_addr.
>
> Can we maybe add a comment? This looks quite hacky ;)
This whole construction is roughly the same as having sigill.s file
with:
.globl expected_si_addr
expected_si_addr: .byte 0,0
.globl expected_psw_addr
expected_psw_addr: br 14
and sigill.h file with:
void expected_si_addr(void);
extern char expected_psw_addr[];
Doing it this way would complicate the build, so I thought it would be
better to just put everything into a single file.
