Commit-ID:  03b099bdcdf7125d4a63dc9ddeefdd454e05123d
Gitweb:     https://git.kernel.org/tip/03b099bdcdf7125d4a63dc9ddeefdd454e05123d
Author:     Matthew Whitehead <tedheads...@gmail.com>
AuthorDate: Fri, 21 Sep 2018 17:20:40 -0400
Committer:  Borislav Petkov <b...@suse.de>
CommitDate: Sat, 22 Sep 2018 11:46:56 +0200

x86/CPU: Use correct macros for Cyrix calls

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: Matthew Whitehead <tedheads...@gmail.com>
Signed-off-by: Borislav Petkov <b...@suse.de>
Reviewed-by: Andy Lutomirski <l...@amacapital.net>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Cc: "H. Peter Anvin" <h...@zytor.com>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Jia Zhang <qianyue...@alibaba-inc.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Philippe Ombredanne <pombreda...@nexb.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Link: http://lkml.kernel.org/r/20180921212041.13096-2-tedheads...@gmail.com
---
 arch/x86/kernel/cpu/cyrix.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
index 8949b7ae6d92..d12226f60168 100644
--- a/arch/x86/kernel/cpu/cyrix.c
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -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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