hardcoded SIGSEGV in __die() ?

[Joakim Tjernlund]

On Wed, 2020-03-25 at 17:02 +0000, David Laight wrote:
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> From: Joakim Tjernlund
> > Sent: 23 March 2020 15:45
> ...
> > > > I tried to follow that chain thinking it would end up sending a
> > > > signal to user space but I cannot
> > see
> > > > that happens. Seems to be related to debugging.
> > > > 
> > > > In short, I cannot see any signal being delivered to user
> > > > space. If so that would explain why
> > > > our user space process never dies.
> > > > Is there a signal hidden in machine_check handler for SIGBUS I
> > > > cannot see?
> > > > 
> > > 
> > > Isn't it done in do_exit(), called from oops_end() ?
> > 
> > hmm, so it seems. The odd thing though is that do_exit takes an
> > exit code, not signal number.
> > Also, feels a bit odd to force an exit(that we haven't seen
> > happening) rather than just a signal.
> 
> Isn't there something 'magic' that converts EFAULT into SIGSEGV?

I have tried to find out and I cannot see a signal beeing sent.
Also, SEGV is wrong, this is a SIGBUS fault.

> 
>         David
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