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-rw-r--r--arch/x86/kernel/process.c72
1 files changed, 45 insertions, 27 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index ad9540676fcc..e7e35219b32f 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -20,7 +20,6 @@
#include <asm/idle.h>
#include <asm/uaccess.h>
#include <asm/i387.h>
-#include <asm/ds.h>
#include <asm/debugreg.h>
unsigned long idle_halt;
@@ -32,26 +31,22 @@ struct kmem_cache *task_xstate_cachep;
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
+ int ret;
+
*dst = *src;
- if (src->thread.xstate) {
- dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
- GFP_KERNEL);
- if (!dst->thread.xstate)
- return -ENOMEM;
- WARN_ON((unsigned long)dst->thread.xstate & 15);
- memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
+ if (fpu_allocated(&src->thread.fpu)) {
+ memset(&dst->thread.fpu, 0, sizeof(dst->thread.fpu));
+ ret = fpu_alloc(&dst->thread.fpu);
+ if (ret)
+ return ret;
+ fpu_copy(&dst->thread.fpu, &src->thread.fpu);
}
return 0;
}
void free_thread_xstate(struct task_struct *tsk)
{
- if (tsk->thread.xstate) {
- kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
- tsk->thread.xstate = NULL;
- }
-
- WARN(tsk->thread.ds_ctx, "leaking DS context\n");
+ fpu_free(&tsk->thread.fpu);
}
void free_thread_info(struct thread_info *ti)
@@ -198,11 +193,16 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
prev = &prev_p->thread;
next = &next_p->thread;
- if (test_tsk_thread_flag(next_p, TIF_DS_AREA_MSR) ||
- test_tsk_thread_flag(prev_p, TIF_DS_AREA_MSR))
- ds_switch_to(prev_p, next_p);
- else if (next->debugctlmsr != prev->debugctlmsr)
- update_debugctlmsr(next->debugctlmsr);
+ if (test_tsk_thread_flag(prev_p, TIF_BLOCKSTEP) ^
+ test_tsk_thread_flag(next_p, TIF_BLOCKSTEP)) {
+ unsigned long debugctl = get_debugctlmsr();
+
+ debugctl &= ~DEBUGCTLMSR_BTF;
+ if (test_tsk_thread_flag(next_p, TIF_BLOCKSTEP))
+ debugctl |= DEBUGCTLMSR_BTF;
+
+ update_debugctlmsr(debugctl);
+ }
if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^
test_tsk_thread_flag(next_p, TIF_NOTSC)) {
@@ -526,21 +526,39 @@ static int __cpuinit mwait_usable(const struct cpuinfo_x86 *c)
}
/*
- * Check for AMD CPUs, which have potentially C1E support
+ * Check for AMD CPUs, where APIC timer interrupt does not wake up CPU from C1e.
+ * For more information see
+ * - Erratum #400 for NPT family 0xf and family 0x10 CPUs
+ * - Erratum #365 for family 0x11 (not affected because C1e not in use)
*/
static int __cpuinit check_c1e_idle(const struct cpuinfo_x86 *c)
{
+ u64 val;
if (c->x86_vendor != X86_VENDOR_AMD)
- return 0;
-
- if (c->x86 < 0x0F)
- return 0;
+ goto no_c1e_idle;
/* Family 0x0f models < rev F do not have C1E */
- if (c->x86 == 0x0f && c->x86_model < 0x40)
- return 0;
+ if (c->x86 == 0x0F && c->x86_model >= 0x40)
+ return 1;
- return 1;
+ if (c->x86 == 0x10) {
+ /*
+ * check OSVW bit for CPUs that are not affected
+ * by erratum #400
+ */
+ if (cpu_has(c, X86_FEATURE_OSVW)) {
+ rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, val);
+ if (val >= 2) {
+ rdmsrl(MSR_AMD64_OSVW_STATUS, val);
+ if (!(val & BIT(1)))
+ goto no_c1e_idle;
+ }
+ }
+ return 1;
+ }
+
+no_c1e_idle:
+ return 0;
}
static cpumask_var_t c1e_mask;