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Subject: Re: [PATCH] x86/entry: Improve system call entry comments
To: Ingo Molnar <mingo@kernel.org>
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Cc: Andy Lutomirski <luto@kernel.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org, Borislav Petkov <bp@alien8.de>,
        Oleg Nesterov <oleg@redhat.com>,
        Andrew Cooper <andrew.cooper3@citrix.com>,
        Brian Gerst <brgerst@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Thomas Gleixner <tglx@linutronix.de>
From: "H. Peter Anvin" <hpa@zytor.com>
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Date: Tue, 8 Mar 2016 10:40:24 -0800
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On 03/08/16 02:30, Ingo Molnar wrote:
>>>> + *
>>>> + * This is considered a slow path.  It is not used by modern libc
>>>> + * implementations on modern hardware except during process startup.
>>>> + *
>>
>> Sadly I believe Android still uses int $0x80 in the upstream version.
> 
> I don't see how that fact conflicts with my statement: on 64-bit kernels INT $0x80 
> will (of course) work, but will land on another entry point: entry_INT80_compat(), 
> not entry_INT80_32().
> 
> On 32-bit kernels the INT $0x80 entry point is entry_INT80_32().
> 

It doesn't.  I was referring to the above quote. Trying to fix that.

	-hpa