UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

x86, AMD: Correct {rd,wr}msr_amd_safe warnings 

The idea with those routines is to slowly phase them out and not call
them on anything else besides K8. They even have a check for that which,
when called too early, fails. Let me explain:

It gets the cpuinfo_x86 pointer from the per_cpu array and when this
happens for cpu0, before its boot_cpu_data has been copied back to the
per_cpu array in smp_store_boot_cpu_info(), we get an empty struct and
thus the check fails.

Use boot_cpu_data directly instead.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1365436666-9837-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Borislav Petkov 2013-04-08 17:57:45 +02:00
parent 55a36b65ee
commit 682469a5db
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/x86/kernel/cpu/amd.c
View File

@ -20,11 +20,11 @@
static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
{
struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
u32 gprs[8] = { 0 };
int err;
WARN_ONCE((c->x86 != 0xf), "%s should only be used on K8!\n", __func__);
WARN_ONCE((boot_cpu_data.x86 != 0xf),
"%s should only be used on K8!\n", __func__);
gprs[1] = msr;
gprs[7] = 0x9c5a203a;
@ -38,10 +38,10 @@ static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
{
struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
u32 gprs[8] = { 0 };
WARN_ONCE((c->x86 != 0xf), "%s should only be used on K8!\n", __func__);
WARN_ONCE((boot_cpu_data.x86 != 0xf),
"%s should only be used on K8!\n", __func__);
gprs[0] = (u32)val;
gprs[1] = msr;