diff options
Diffstat (limited to 'arch/x86/include/asm/fpu')
| -rw-r--r-- | arch/x86/include/asm/fpu/api.h | 3 | ||||
| -rw-r--r-- | arch/x86/include/asm/fpu/sched.h | 38 | ||||
| -rw-r--r-- | arch/x86/include/asm/fpu/types.h | 24 | ||||
| -rw-r--r-- | arch/x86/include/asm/fpu/xstate.h | 3 |
4 files changed, 29 insertions, 39 deletions
diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h index f42de5f05e7e..cd6f194a912b 100644 --- a/arch/x86/include/asm/fpu/api.h +++ b/arch/x86/include/asm/fpu/api.h @@ -126,6 +126,7 @@ static inline void fpstate_init_soft(struct swregs_state *soft) {} #endif /* State tracking */ +DECLARE_PER_CPU(bool, kernel_fpu_allowed); DECLARE_PER_CPU(struct fpu *, fpu_fpregs_owner_ctx); /* Process cleanup */ @@ -136,7 +137,7 @@ static inline void fpstate_free(struct fpu *fpu) { } #endif /* fpstate-related functions which are exported to KVM */ -extern void fpstate_clear_xstate_component(struct fpstate *fps, unsigned int xfeature); +extern void fpstate_clear_xstate_component(struct fpstate *fpstate, unsigned int xfeature); extern u64 xstate_get_guest_group_perm(void); diff --git a/arch/x86/include/asm/fpu/sched.h b/arch/x86/include/asm/fpu/sched.h index c485f1944c5f..c060549c6c94 100644 --- a/arch/x86/include/asm/fpu/sched.h +++ b/arch/x86/include/asm/fpu/sched.h @@ -10,7 +10,7 @@ #include <asm/trace/fpu.h> extern void save_fpregs_to_fpstate(struct fpu *fpu); -extern void fpu__drop(struct fpu *fpu); +extern void fpu__drop(struct task_struct *tsk); extern int fpu_clone(struct task_struct *dst, unsigned long clone_flags, bool minimal, unsigned long shstk_addr); extern void fpu_flush_thread(void); @@ -18,31 +18,25 @@ extern void fpu_flush_thread(void); /* * FPU state switching for scheduling. * - * This is a two-stage process: + * switch_fpu() saves the old state and sets TIF_NEED_FPU_LOAD if + * TIF_NEED_FPU_LOAD is not set. This is done within the context + * of the old process. * - * - switch_fpu_prepare() saves the old state. - * This is done within the context of the old process. - * - * - switch_fpu_finish() sets TIF_NEED_FPU_LOAD; the floating point state - * will get loaded on return to userspace, or when the kernel needs it. - * - * If TIF_NEED_FPU_LOAD is cleared then the CPU's FPU registers - * are saved in the current thread's FPU register state. - * - * If TIF_NEED_FPU_LOAD is set then CPU's FPU registers may not - * hold current()'s FPU registers. It is required to load the + * Once TIF_NEED_FPU_LOAD is set, it is required to load the * registers before returning to userland or using the content * otherwise. * * The FPU context is only stored/restored for a user task and * PF_KTHREAD is used to distinguish between kernel and user threads. */ -static inline void switch_fpu_prepare(struct task_struct *old, int cpu) +static inline void switch_fpu(struct task_struct *old, int cpu) { - if (cpu_feature_enabled(X86_FEATURE_FPU) && + if (!test_tsk_thread_flag(old, TIF_NEED_FPU_LOAD) && + cpu_feature_enabled(X86_FEATURE_FPU) && !(old->flags & (PF_KTHREAD | PF_USER_WORKER))) { - struct fpu *old_fpu = &old->thread.fpu; + struct fpu *old_fpu = x86_task_fpu(old); + set_tsk_thread_flag(old, TIF_NEED_FPU_LOAD); save_fpregs_to_fpstate(old_fpu); /* * The save operation preserved register state, so the @@ -50,7 +44,7 @@ static inline void switch_fpu_prepare(struct task_struct *old, int cpu) * current CPU number in @old_fpu, so the next return * to user space can avoid the FPU register restore * when is returns on the same CPU and still owns the - * context. + * context. See fpregs_restore_userregs(). */ old_fpu->last_cpu = cpu; @@ -58,14 +52,4 @@ static inline void switch_fpu_prepare(struct task_struct *old, int cpu) } } -/* - * Delay loading of the complete FPU state until the return to userland. - * PKRU is handled separately. - */ -static inline void switch_fpu_finish(struct task_struct *new) -{ - if (cpu_feature_enabled(X86_FEATURE_FPU)) - set_tsk_thread_flag(new, TIF_NEED_FPU_LOAD); -} - #endif /* _ASM_X86_FPU_SCHED_H */ diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index de16862bf230..1c94121acd3d 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -125,6 +125,7 @@ enum xfeature { XFEATURE_RSRVD_COMP_16, XFEATURE_XTILE_CFG, XFEATURE_XTILE_DATA, + XFEATURE_APX, XFEATURE_MAX, }; @@ -145,6 +146,7 @@ enum xfeature { #define XFEATURE_MASK_LBR (1 << XFEATURE_LBR) #define XFEATURE_MASK_XTILE_CFG (1 << XFEATURE_XTILE_CFG) #define XFEATURE_MASK_XTILE_DATA (1 << XFEATURE_XTILE_DATA) +#define XFEATURE_MASK_APX (1 << XFEATURE_APX) #define XFEATURE_MASK_FPSSE (XFEATURE_MASK_FP | XFEATURE_MASK_SSE) #define XFEATURE_MASK_AVX512 (XFEATURE_MASK_OPMASK \ @@ -304,6 +306,13 @@ struct xtile_data { } __packed; /* + * State component 19: 8B extended general purpose register. + */ +struct apx_state { + u64 egpr[16]; +} __packed; + +/* * State component 10 is supervisor state used for context-switching the * PASID state. */ @@ -407,9 +416,11 @@ struct fpu_state_perm { /* * @__state_perm: * - * This bitmap indicates the permission for state components, which - * are available to a thread group. The permission prctl() sets the - * enabled state bits in thread_group_leader()->thread.fpu. + * This bitmap indicates the permission for state components + * available to a thread group, including both user and supervisor + * components and software-defined bits like FPU_GUEST_PERM_LOCKED. + * The permission prctl() sets the enabled state bits in + * thread_group_leader()->thread.fpu. * * All run time operations use the per thread information in the * currently active fpu.fpstate which contains the xfeature masks @@ -525,13 +536,6 @@ struct fpu_guest { u64 xfeatures; /* - * @perm: xfeature bitmap of features which are - * permitted to be enabled for the guest - * vCPU. - */ - u64 perm; - - /* * @xfd_err: Save the guest value. */ u64 xfd_err; diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index 7f39fe7980c5..b308a76afbb7 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -32,7 +32,8 @@ XFEATURE_MASK_PKRU | \ XFEATURE_MASK_BNDREGS | \ XFEATURE_MASK_BNDCSR | \ - XFEATURE_MASK_XTILE) + XFEATURE_MASK_XTILE | \ + XFEATURE_MASK_APX) /* * Features which are restored when returning to user space. |