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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Andy Lutomirski <luto@kernel.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Oleg Nesterov <oleg@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Lutomirski <luto@kernel.org>,
        Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@kernel.org>,
        Jan Kratochvil <jan.kratochvil@redhat.com>,
        Pedro Alves <palves@redhat.com>, Peter Anvin <hpa@zytor.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>
Subject: Re: [PATCH v2 0/4] x86: fix get_nr_restart_syscall()
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References: <20191126110659.GA14042@redhat.com> <20191203141239.GA30688@redhat.com> <20191218151904.GA3127@redhat.com> <CAHk-=whNhwFigBDSnyrfJYxr-uAe6PHiWTcHcZzPW+vZ3eWAXw@mail.gmail.com> <CALCETrWJ8PLbxvX6yuP7Q3kz_=dZinacUd-3-OqUkZNSMCE34g@mail.gmail.com>
Date:   Mon, 17 Feb 2020 16:54:02 +0100
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Andy Lutomirski <luto@kernel.org> writes:

> On Wed, Dec 18, 2019 at 12:02 PM Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
>>
>> On Wed, Dec 18, 2019 at 7:19 AM Oleg Nesterov <oleg@redhat.com> wrote:
>> >
>> > Andy, Linus, do you have any objections?
>>
>> It's ok by me, no objections. I still don't love your "hide the bit in
>> thread flags over return to user space", and would still prefer it in
>> the restart block, but I don't care _that_ deeply.
>>
>
> I'd rather stick it in restart_block.  I'd also like to see the kernel
> *verify* that the variant of restart_syscall() that's invoked is the
> same as the variant that should be invoked.  In my mind, very few
> syscalls say "I can't believe there are no major bugs in here" like
> restart_syscall(), and being conservative is nice.

Just mopping up my backlog. What happened to this?