On Wed, 2020-03-25 at 17:02 +0000, David Laight wrote:

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From: Joakim Tjernlund

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Sent: 23 March 2020 15:45

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I tried to follow that chain thinking it would end up sending a
signal to user space but I cannot

see

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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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