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References: <20220103181956.983342-1-walt@drummond.us> <YdNE6UXRT02135Pd@zeniv-ca.linux.org.uk>
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From:   Walt Drummond <walt@drummond.us>
Date:   Mon, 3 Jan 2022 17:00:58 -0800
Message-ID: <CADCN6nx4VWtR79TBDTENRExjsa=KAGuUpyz06iu2EGmSTPyc+Q@mail.gmail.com>
Subject: Re: [RFC PATCH 0/8] signals: Support more than 64 signals
To:     Al Viro <viro@zeniv.linux.org.uk>
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I simply wanted SIGINFO and VSTATUS, and that necessitated this. If
the limit of 1024 rt signals is an issue, that's an extremely simple
change to make.


On Mon, Jan 3, 2022 at 10:48 AM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> On Mon, Jan 03, 2022 at 10:19:48AM -0800, Walt Drummond wrote:
> > This patch set expands the number of signals in Linux beyond the
> > current cap of 64.  It sets a new cap at the somewhat arbitrary limit
> > of 1024 signals, both because it=E2=80=99s what GLibc and MUSL support =
and
> > because many architectures pad sigset_t or ucontext_t in the kernel to
> > this cap.  This limit is not fixed and can be further expanded within
> > reason.
>
> Could you explain the point of the entire exercise?  Why do we need more
> rt signals in the first place?
>
> glibc has quite a bit of utterly pointless future-proofing.  So "they
> allow more" is not a good reason - not without a plausible use-case,
> at least.