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-rw-r--r--arch/x86/include/asm/fpu/api.h3
-rw-r--r--arch/x86/include/asm/fpu/sched.h38
-rw-r--r--arch/x86/include/asm/fpu/types.h73
-rw-r--r--arch/x86/include/asm/fpu/xstate.h12
4 files changed, 78 insertions, 48 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..93e99d2583d6 100644
--- a/arch/x86/include/asm/fpu/types.h
+++ b/arch/x86/include/asm/fpu/types.h
@@ -118,13 +118,14 @@ enum xfeature {
XFEATURE_PKRU,
XFEATURE_PASID,
XFEATURE_CET_USER,
- XFEATURE_CET_KERNEL_UNUSED,
+ XFEATURE_CET_KERNEL,
XFEATURE_RSRVD_COMP_13,
XFEATURE_RSRVD_COMP_14,
XFEATURE_LBR,
XFEATURE_RSRVD_COMP_16,
XFEATURE_XTILE_CFG,
XFEATURE_XTILE_DATA,
+ XFEATURE_APX,
XFEATURE_MAX,
};
@@ -141,10 +142,11 @@ enum xfeature {
#define XFEATURE_MASK_PKRU (1 << XFEATURE_PKRU)
#define XFEATURE_MASK_PASID (1 << XFEATURE_PASID)
#define XFEATURE_MASK_CET_USER (1 << XFEATURE_CET_USER)
-#define XFEATURE_MASK_CET_KERNEL (1 << XFEATURE_CET_KERNEL_UNUSED)
+#define XFEATURE_MASK_CET_KERNEL (1 << XFEATURE_CET_KERNEL)
#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 \
@@ -267,6 +269,16 @@ struct cet_user_state {
};
/*
+ * State component 12 is Control-flow Enforcement supervisor states.
+ * This state includes SSP pointers for privilege levels 0 through 2.
+ */
+struct cet_supervisor_state {
+ u64 pl0_ssp;
+ u64 pl1_ssp;
+ u64 pl2_ssp;
+} __packed;
+
+/*
* State component 15: Architectural LBR configuration state.
* The size of Arch LBR state depends on the number of LBRs (lbr_depth).
*/
@@ -304,6 +316,13 @@ 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 +426,11 @@ 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 +546,6 @@ 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;
@@ -548,6 +562,31 @@ struct fpu_guest {
};
/*
+ * FPU state configuration data for fpu_guest.
+ * Initialized at boot time. Read only after init.
+ */
+struct vcpu_fpu_config {
+ /*
+ * @size:
+ *
+ * The default size of the register state buffer in guest FPUs.
+ * Includes all supported features except independent managed
+ * features and features which have to be requested by user space
+ * before usage.
+ */
+ unsigned int size;
+
+ /*
+ * @features:
+ *
+ * The default supported features bitmap in guest FPUs. Does not
+ * include independent managed features and features which have to
+ * be requested by user space before usage.
+ */
+ u64 features;
+};
+
+/*
* FPU state configuration data. Initialized at boot time. Read only after init.
*/
struct fpu_state_config {
@@ -563,8 +602,9 @@ struct fpu_state_config {
* @default_size:
*
* The default size of the register state buffer. Includes all
- * supported features except independent managed features and
- * features which have to be requested by user space before usage.
+ * supported features except independent managed features,
+ * guest-only features and features which have to be requested by
+ * user space before usage.
*/
unsigned int default_size;
@@ -580,8 +620,8 @@ struct fpu_state_config {
* @default_features:
*
* The default supported features bitmap. Does not include
- * independent managed features and features which have to
- * be requested by user space before usage.
+ * independent managed features, guest-only features and features
+ * which have to be requested by user space before usage.
*/
u64 default_features;
/*
@@ -602,5 +642,6 @@ struct fpu_state_config {
/* FPU state configuration information */
extern struct fpu_state_config fpu_kernel_cfg, fpu_user_cfg;
+extern struct vcpu_fpu_config guest_default_cfg;
#endif /* _ASM_X86_FPU_TYPES_H */
diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h
index 7f39fe7980c5..7a7dc9d56027 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.
@@ -45,9 +46,13 @@
/* Features which are dynamically enabled for a process on request */
#define XFEATURE_MASK_USER_DYNAMIC XFEATURE_MASK_XTILE_DATA
+/* Supervisor features which are enabled only in guest FPUs */
+#define XFEATURE_MASK_GUEST_SUPERVISOR XFEATURE_MASK_CET_KERNEL
+
/* All currently supported supervisor features */
#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (XFEATURE_MASK_PASID | \
- XFEATURE_MASK_CET_USER)
+ XFEATURE_MASK_CET_USER | \
+ XFEATURE_MASK_GUEST_SUPERVISOR)
/*
* A supervisor state component may not always contain valuable information,
@@ -74,8 +79,7 @@
* Unsupported supervisor features. When a supervisor feature in this mask is
* supported in the future, move it to the supported supervisor feature mask.
*/
-#define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED (XFEATURE_MASK_PT | \
- XFEATURE_MASK_CET_KERNEL)
+#define XFEATURE_MASK_SUPERVISOR_UNSUPPORTED (XFEATURE_MASK_PT)
/* All supervisor states including supported and unsupported states. */
#define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \