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Subject: Re: [PATCH RFC v10 2/6] x86/entry: Add STACKLEAK erasing the kernel
 stack at the end of syscalls
To: alex.popov@linux.com, Boris Lukashev <blukashev@sempervictus.com>,
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From: Dave Hansen <dave.hansen@linux.intel.com>
Message-ID: <df64b4d8-7780-4cb4-4b05-bd5842ea1a39@linux.intel.com>
Date: Thu, 29 Mar 2018 14:00:28 -0700
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On 03/29/2018 01:56 PM, Alexander Popov wrote:
> 
> If STACKLEAK is not banned, would you like me to introduce ERASE_KSTACK (for
> cases 1 and 3) and ERASE_KSTACK_NOCLOBBER (for case 2) in
> arch/x86/entry/calling.h?

Yes, please.  But, whatever you do, I think having each name have
constant behavior is a must.  Please don't have "ERASE_KSTACK" in one
file clobber and another not clobber (even if one is 32-bit and the
other is not).