提交 d26ad73b 编写于 作者: M Matthew Whitehead 提交者: Greg Kroah-Hartman

x86/CPU: Use correct macros for Cyrix calls

[ Upstream commit 03b099bdcdf7125d4a63dc9ddeefdd454e05123d ]

There are comments in processor-cyrix.h advising you to _not_ make calls
using the deprecated macros in this style:

  setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);

This is because it expands the macro into a non-functioning calling
sequence. The calling order must be:

  outb(CX86_CCR2, 0x22);
  inb(0x23);

From the comments:

 * When using the old macros a line like
 *   setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
 * gets expanded to:
 *  do {
 *    outb((CX86_CCR2), 0x22);
 *    outb((({
 *        outb((CX86_CCR2), 0x22);
 *        inb(0x23);
 *    }) | 0x88), 0x23);
 *  } while (0);

The new macros fix this problem, so use them instead.
Signed-off-by: NMatthew Whitehead <tedheadster@gmail.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NAndy Lutomirski <luto@amacapital.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jia Zhang <qianyue.zj@alibaba-inc.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180921212041.13096-2-tedheadster@gmail.comSigned-off-by: NSasha Levin <sashal@kernel.org>
上级 fd3f592b
......@@ -437,7 +437,7 @@ static void cyrix_identify(struct cpuinfo_x86 *c)
/* enable MAPEN */
setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
/* enable cpuid */
setCx86_old(CX86_CCR4, getCx86_old(CX86_CCR4) | 0x80);
setCx86(CX86_CCR4, getCx86(CX86_CCR4) | 0x80);
/* disable MAPEN */
setCx86(CX86_CCR3, ccr3);
local_irq_restore(flags);
......
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