kern/98460 : [kernel] [patch] fpu_clean_state() cannot be disabled for not AMD processors, those are not vulnerable to FreeBSD-SA-06:14.fpu

[Rostislav Krasny]

The following reply was made to PR kern/98460; it has been noted by GNATS.

From: Rostislav Krasny <rosti.bsd at gmail.com>
To: Bruce Evans <bde at zeta.org.au>
Cc: freebsd-gnats-submit at freebsd.org
Subject: Re: kern/98460 : [kernel] [patch] fpu_clean_state() cannot be
 disabled for not AMD processors, those are not vulnerable to
 FreeBSD-SA-06:14.fpu
Date: Sat, 17 Jun 2006 01:58:24 +0300

 ... or even much shorter version:
 
 		.byte	0xEB;		\n\	/* short JMP */
 	l0:	.byte	0x00;		\n\	/* where to jump */
 	l1:	bt	$1,%%ax;	\n\	/* CPU_FXSR_NEEDCLEAN bit */
 		jc	l2;		\n\
 		movb	$(l5-l1),l0;	\n\
 		jmp	l5;		\n\
 	l2:	movb	$(l3-l1),l0;	\n\
 	l3:	fnstsw	%%ax;		\n\
 		ffree	%%st(7);	\n\
 		bt	$7,%%ax;	\n\
 		jnc	l4;		\n\
 		fnclex;			\n\
 	l4:	fildl	safe_address;	\n\
 	l5:				\n\