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Date:   Tue, 5 Nov 2019 15:53:43 +0100 (CET)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     Florian Weimer <fweimer@redhat.com>
cc:     Carlos O'Donell <carlos@redhat.com>, Shawn Landden <shawn@git.icu>,
        libc-alpha@sourceware.org, linux-api@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Deepa Dinamani <deepa.kernel@gmail.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Keith Packard <keithp@keithp.com>,
        Peter Zijlstra <peterz@infradead.org>
Subject: Re: [RFC v2 PATCH] futex: extend set_robust_list to allow 2 locking
 ABIs at the same time.
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On Tue, 5 Nov 2019, Florian Weimer wrote:
> * Carlos O'Donell:
> > "Robust mutexes do not take ROBUST_LIST_LIMIT into account"
> > https://sourceware.org/bugzilla/show_bug.cgi?id=19089
> 
> That's just a missing check in our implementation and something that few
> applications will encounter, if any.  There is this one here:
> 
>   <https://sourceware.org/bugzilla/show_bug.cgi?id=19004>
> 
> It contains a kernel patch.
> 
> I thought that there were more issues in the current implementation, but
> I can't a record of them. 8-(

There is a nasty one in my inbox with a kernel patch fixing it, which I
still need to review with all futex brain cells activated:

  https://lore.kernel.org/r/1572573789-16557-1-git-send-email-wang.yi59@zte.com.cn

Thanks,

	tglx