Re: [PATCH v3 0/2] target/s390x: Fix SIGILL psw.addr reporting

[jonathan.albrecht]

On 2021-06-21 8:00 am, Ilya Leoshkevich wrote:
> On Thu, 2021-06-10 at 11:49 +0200, David Hildenbrand wrote:
> > On 02.06.21 02:22, Ilya Leoshkevich wrote:
> > > qemu-s390x puts a wrong value into SIGILL's siginfo_t's psw.addr:
> > > it
> > > should be a pointer to the instruction following the illegal
> > > instruction, but at the moment it is a pointer to the illegal
> > > instruction itself. This breaks OpenJDK, which relies on this
> > > value.
> > >
> > > Patch 1 fixes the issue, patch 2 adds a test.
> > >
> > > v1:
> > > https://lists.nongnu.org/archive/html/qemu-devel/2021-05/msg06592.html
> > > v1 -> v2: Use a better buglink (Cornelia), simplify the inline asm
> > >            magic in the test and add an explanation (David).
> > >
> > > v2:
> > > https://lists.nongnu.org/archive/html/qemu-devel/2021-05/msg06649.html
> > > v2 -> v3: Fix SIGSEGV handling (found when trying to run valgrind
> > > under
> > >            qemu-user).
> > >
> >
> > There might still be something wrong:
> >
> > https://gitlab.com/qemu-project/qemu/-/issues/319
> >
> > At least it smells like some more signal (mis)handling.
>
> I've taken another look, and it must be compare-and-trap SIGFPE/SIGILL
> mixup. I think I will just fix it here in v4.

Yes, I've been looking at it too and found it is a compare-and-trap
SIGFPE/SIGILL mixup. I was about to send out a patch if you want
to wait. I should be able to send it out in an hour.

Jon

> Best regards,
> Ilya