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Date: Wed, 22 Apr 2020 17:31:07 +1000
From: Nicholas Piggin <npiggin@gmail.com>
Subject: Re: [musl] Re: Powerpc Linux 'scv' system call ABI proposal take 2
To: Florian Weimer <fw@deneb.enyo.de>
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Cc: Rich Felker <dalias@libc.org>,
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Excerpts from Florian Weimer's message of April 22, 2020 5:15 pm:
> * Nicholas Piggin:
>=20
>> Another option would be to use a different signal. I don't see that any=20
>> are more suitable.
>=20
> SIGSYS comes to my mind.  But I don't know how exclusively it is
> associated with seccomp these days.

SIGSYS is entirely seccomp now. There looks like a single obscure MIPS=20
user of it in Linux that's not seccomp, but it would be entirely new for=20
powerpc (or any of the common platforms, arm, x86 etc).

So I would be disinclined to use SIGSYS unless there are no other better=20
signal types, and we don't want to use SIGILL for some good reason -- is=20
there a good reason to add complexity for userspace by differentiating=20
these two situations?

Thanks,
Nick