From: Rich Felker <dalias@libc.org>
To: Dominic Chen <d.c.ddcc@gmail.com>
Cc: Carlos O'Donell <carlos@redhat.com>,
musl@lists.openwall.com, fweimer@redhat.com
Subject: Re: [musl] Incorrect thread TID caching
Date: Thu, 4 Feb 2021 11:15:25 -0500 [thread overview]
Message-ID: <20210204161523.GZ23432@brightrain.aerifal.cx> (raw)
In-Reply-To: <51614DF7-9976-48D3-92F2-B927FCE18663@gmail.com>
On Wed, Feb 03, 2021 at 11:22:18PM -0500, Dominic Chen wrote:
>
> > On Feb 3, 2021, at 10:28 PM, Carlos O'Donell <carlos@redhat.com> wrote:
> >
> > As Rich said for musl, this is not ABI for glibc either.
> >
> > I'm not sure why you need to reset the TID cache. In glibc we have
> > containerized tests and we do not need to change internals of the
> > runtime e.g. unshare (CLONE_NEWUSER, CLONE_NEWPID, CLONE_NEWNS);
> > (see glibc/support/test-container.c).
>
>
> Thanks for the advice; sounds like I should just modify my local
> musl to call gettid directly in raise().
No, as noted earlier in this thread we should fix clone() to be like
_Fork() at least in the case where it's not doing things that are
inherently unsafe (CLONE_VM etc.) -- as long as you're making a new
process with normal process semantics, the child should be able to
safely call any AS-safe function in libc, or any function in libc at
all if the parent is not multi-threaded.
The possibility of changing raise() is just for the sake of vfork()
and is independent of the issue here.
Rich
prev parent reply other threads:[~2021-02-04 16:15 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-03 4:04 Dominic Chen
2021-02-03 7:16 ` Florian Weimer
2021-02-03 19:21 ` Rich Felker
2021-02-03 20:21 ` Dominic Chen
2021-02-03 21:01 ` Rich Felker
2021-02-03 22:30 ` Dominic Chen
2021-02-03 22:55 ` Rich Felker
2021-02-15 16:56 ` Rich Felker
2021-02-17 19:49 ` Dominic Chen
2021-02-17 20:11 ` Rich Felker
2021-02-17 21:07 ` Rich Felker
2021-03-12 21:14 ` Dominic Chen
2021-02-04 3:28 ` Carlos O'Donell
2021-02-04 4:22 ` Dominic Chen
2021-02-04 16:15 ` Rich Felker [this message]
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