cpuid: Fix pointer arithmetic

Commit 208fb9613c8c151b2885e89066a3eb22a977df6f (Fix up aliasing warnings.)
changed pointer arithmetic in one part of cpuid function from

  -               if (eax!=0)     *eax = (*(unsigned *)(buffer   ));
  -               if (ebx!=0)     *ebx = (*(unsigned *)(buffer+ 4));
  -               if (ecx!=0)     *ecx = (*(unsigned *)(buffer+ 8));
  -               if (edx!=0)     *edx = (*(unsigned *)(buffer+12));
  +               if (eax!=0)     *eax = *(ptr)++;
  +               if (ebx!=0)     *ebx = *(ptr)++;
  +               if (ecx!=0)     *ecx = *(ptr)++;
  +               if (edx!=0)     *edx = *(ptr);

The post-increment is not equal to what was used before. This
causes generation of wrong cpuid information, e.g. lsmsr fails:

$ ./lsmsr -a -l
CPU not (yet) supported (vendor="(unknown)", family=16, model=10)

Fix this by pre-incrementing the pointer before it is dereferenced.

Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/cpuid.c b/cpuid.c
index 290aadd..82a104d 100644
--- a/cpuid.c
+++ b/cpuid.c
@@ -191,10 +191,10 @@ void cpuid(unsigned int CPU_number, unsigned long long idx,
 			perror(cpuname);
 			exit(EXIT_FAILURE);
 		}
-		if (eax!=0)	*eax = *(ptr)++;
-		if (ebx!=0)	*ebx = *(ptr)++;
-		if (ecx!=0)	*ecx = *(ptr)++;
-		if (edx!=0)	*edx = *(ptr);
+		if (eax!=0)	*eax = *ptr;
+		if (ebx!=0)	*ebx = *(++ptr);
+		if (ecx!=0)	*ecx = *(++ptr);
+		if (edx!=0)	*edx = *(++ptr);
 		if (close(fh) == -1) {
 			perror("close");
 			exit(EXIT_FAILURE);