diff options
Diffstat (limited to 'arch/x86/kernel/fpu/core.c')
| -rw-r--r-- | arch/x86/kernel/fpu/core.c | 53 |
1 files changed, 35 insertions, 18 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 12c70840980e..06c818967bb6 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -291,15 +291,13 @@ void fpu__drop(struct fpu *fpu) } /* - * Clear FPU registers by setting them up from - * the init fpstate: + * Clear FPU registers by setting them up from the init fpstate. + * Caller must do fpregs_[un]lock() around it. */ -static inline void copy_init_fpstate_to_fpregs(void) +static inline void copy_init_fpstate_to_fpregs(u64 features_mask) { - fpregs_lock(); - if (use_xsave()) - copy_kernel_to_xregs(&init_fpstate.xsave, -1); + copy_kernel_to_xregs(&init_fpstate.xsave, features_mask); else if (static_cpu_has(X86_FEATURE_FXSR)) copy_kernel_to_fxregs(&init_fpstate.fxsave); else @@ -307,9 +305,6 @@ static inline void copy_init_fpstate_to_fpregs(void) if (boot_cpu_has(X86_FEATURE_OSPKE)) copy_init_pkru_to_fpregs(); - - fpregs_mark_activate(); - fpregs_unlock(); } /* @@ -318,18 +313,40 @@ static inline void copy_init_fpstate_to_fpregs(void) * Called by sys_execve(), by the signal handler code and by various * error paths. */ -void fpu__clear(struct fpu *fpu) +static void fpu__clear(struct fpu *fpu, bool user_only) { - WARN_ON_FPU(fpu != ¤t->thread.fpu); /* Almost certainly an anomaly */ + WARN_ON_FPU(fpu != ¤t->thread.fpu); - fpu__drop(fpu); + if (!static_cpu_has(X86_FEATURE_FPU)) { + fpu__drop(fpu); + fpu__initialize(fpu); + return; + } - /* - * Make sure fpstate is cleared and initialized. - */ - fpu__initialize(fpu); - if (static_cpu_has(X86_FEATURE_FPU)) - copy_init_fpstate_to_fpregs(); + fpregs_lock(); + + if (user_only) { + if (!fpregs_state_valid(fpu, smp_processor_id()) && + xfeatures_mask_supervisor()) + copy_kernel_to_xregs(&fpu->state.xsave, + xfeatures_mask_supervisor()); + copy_init_fpstate_to_fpregs(xfeatures_mask_user()); + } else { + copy_init_fpstate_to_fpregs(xfeatures_mask_all); + } + + fpregs_mark_activate(); + fpregs_unlock(); +} + +void fpu__clear_user_states(struct fpu *fpu) +{ + fpu__clear(fpu, true); +} + +void fpu__clear_all(struct fpu *fpu) +{ + fpu__clear(fpu, false); } /* |