diff options
| author | Andi Kleen <ak@suse.de> | 2008-01-30 13:33:21 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:33:21 +0100 |
| commit | 191679fdfa63342752ff6a094a2522ae939b8d0c (patch) | |
| tree | d1d3af246c10ff5201450c270fe3bb9f1bd2bd6f | |
| parent | 404ee5b14b68d3cba287c2596588b83790c49f7b (diff) | |
x86: add noclflush option
To disable CLFLUSH usage, especially in change_page_attr().
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | Documentation/kernel-parameters.txt | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/common.c | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/setup_64.c | 7 |
3 files changed, 16 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index b8fadf5f75a..040e30a33b7 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1191,6 +1191,8 @@ and is between 256 and 4096 characters. It is defined in the file register save and restore. The kernel will only save legacy floating-point registers on task switch. + noclflush [BUGS=X86] Don't use the CLFLUSH instruction + nohlt [BUGS=ARM] no-hlt [BUGS=X86-32] Tells the kernel that the hlt diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index dfc9563fc4f..56b7ea8e6c7 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -542,6 +542,13 @@ void __cpuinit detect_ht(struct cpuinfo_x86 *c) } #endif +static __init int setup_noclflush(char *arg) +{ + setup_clear_cpu_cap(X86_FEATURE_CLFLSH); + return 1; +} +__setup("noclflush", setup_noclflush); + void __cpuinit print_cpu_info(struct cpuinfo_x86 *c) { char *vendor = NULL; diff --git a/arch/x86/kernel/setup_64.c b/arch/x86/kernel/setup_64.c index df159520bbd..cb9b8a90c09 100644 --- a/arch/x86/kernel/setup_64.c +++ b/arch/x86/kernel/setup_64.c @@ -1032,6 +1032,13 @@ void __cpuinit identify_cpu(struct cpuinfo_x86 *c) } +static __init int setup_noclflush(char *arg) +{ + setup_clear_cpu_cap(X86_FEATURE_CLFLSH); + return 1; +} +__setup("noclflush", setup_noclflush); + void __cpuinit print_cpu_info(struct cpuinfo_x86 *c) { if (c->x86_model_id[0]) |