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Date: Fri, 27 Mar 2015 13:09:12 +0100
From: Denys Vlasenko <dvlasenk@redhat.com>
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To: Ingo Molnar <mingo@kernel.org>
CC: Linus Torvalds <torvalds@linux-foundation.org>,
        Steven Rostedt <rostedt@goodmis.org>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>,
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        Alexei Starovoitov <ast@plumgrid.com>, Will Drewry <wad@chromium.org>,
        Kees Cook <keescook@chromium.org>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/4] x86/asm/entry/32: Use PUSH instructions to build
 pt_regs on stack
References: <1427452582-21624-1-git-send-email-dvlasenk@redhat.com> <1427452582-21624-4-git-send-email-dvlasenk@redhat.com> <20150327113252.GB14778@gmail.com>
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On 03/27/2015 12:32 PM, Ingo Molnar wrote:
> 
> * Denys Vlasenko <dvlasenk@redhat.com> wrote:
> 
>> This mimics the recent similar 64-bit change.
>> Saves ~110 bytes of code.
> 
> Would be nice to know whether you tested all the affected system entry 
> variants, on both AMD and Intel CPUs?

Yes, I did. I also looked at the diff of entry_64.o disassembly, to have
a different view of the changes.

I know how fragile this stuff is.