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Diffstat (limited to 'arch/x86/kernel/fpu/core.c')
-rw-r--r--arch/x86/kernel/fpu/core.c24
1 files changed, 19 insertions, 5 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index 67ae18aeaf8b..d1359ea73a96 100644
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -114,6 +114,10 @@ void __kernel_fpu_begin(void)
kernel_fpu_disable();
if (fpu->fpregs_active) {
+ /*
+ * Ignore return value -- we don't care if reg state
+ * is clobbered.
+ */
copy_fpregs_to_fpstate(fpu);
} else {
this_cpu_write(fpu_fpregs_owner_ctx, NULL);
@@ -201,8 +205,12 @@ void fpu__save(struct fpu *fpu)
preempt_disable();
if (fpu->fpregs_active) {
- if (!copy_fpregs_to_fpstate(fpu))
- fpregs_deactivate(fpu);
+ if (!copy_fpregs_to_fpstate(fpu)) {
+ if (use_eager_fpu())
+ copy_kernel_to_fpregs(&fpu->state);
+ else
+ fpregs_deactivate(fpu);
+ }
}
preempt_enable();
}
@@ -271,7 +279,11 @@ static void fpu_copy(struct fpu *dst_fpu, struct fpu *src_fpu)
preempt_disable();
if (!copy_fpregs_to_fpstate(dst_fpu)) {
memcpy(&src_fpu->state, &dst_fpu->state, xstate_size);
- fpregs_deactivate(src_fpu);
+
+ if (use_eager_fpu())
+ copy_kernel_to_fpregs(&src_fpu->state);
+ else
+ fpregs_deactivate(src_fpu);
}
preempt_enable();
}
@@ -421,8 +433,10 @@ static inline void copy_init_fpstate_to_fpregs(void)
{
if (use_xsave())
copy_kernel_to_xregs(&init_fpstate.xsave, -1);
- else
+ else if (static_cpu_has(X86_FEATURE_FXSR))
copy_kernel_to_fxregs(&init_fpstate.fxsave);
+ else
+ copy_kernel_to_fregs(&init_fpstate.fsave);
}
/*
@@ -435,7 +449,7 @@ void fpu__clear(struct fpu *fpu)
{
WARN_ON_FPU(fpu != &current->thread.fpu); /* Almost certainly an anomaly */
- if (!use_eager_fpu()) {
+ if (!use_eager_fpu() || !static_cpu_has(X86_FEATURE_FPU)) {
/* FPU state will be reallocated lazily at the first use. */
fpu__drop(fpu);
} else {