Re: [PATCH 5/5] x86, head_32: Remove an old gcc2 fix

From: H. Peter Anvin
Date: Sat Feb 09 2013 - 17:24:48 EST

On 02/09/2013 01:23 PM, Borislav Petkov wrote:
On Sat, Feb 09, 2013 at 12:52:01PM -0800, H. Peter Anvin wrote:
However... DF should have been cleared long before this...

How about we do this at the beginning of default_entry where we clear

diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index fc56613224c3..8b2a8a824fc6 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -322,10 +322,11 @@ default_entry:
* debugger if this code is traced. Best to initialize before switching to
* protected mode.
pushl $0

+ cld # GCC wants DF=0 at all times

The pushfl/popfl sequence clears DF too...


H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

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