---

yaml
---
r: 287751
b: refs/heads/master
c: 59cca65
h: refs/heads/master
i:
  287749: 79e215e
  287747: 021073e
  287743: 4f58ce1
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7e16838d94b566a17b65231073d179bc04d590c8
+refs/heads/master: 59cca653a601372e9b4a430d867377a3e4a36d76

trunk/arch/x86/include/asm/i387.h

@@ -29,11 +29,10 @@ extern unsigned int sig_xstate_size;
 extern void fpu_init(void);
 extern void mxcsr_feature_mask_init(void);
 extern int init_fpu(struct task_struct *child);
+extern void __math_state_restore(struct task_struct *);
 extern void math_state_restore(void);
 extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);
 
-DECLARE_PER_CPU(struct task_struct *, fpu_owner_task);
-
 extern user_regset_active_fn fpregs_active, xfpregs_active;
 extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get,
 				xstateregs_get;
@@ -270,16 +269,6 @@ static inline int fpu_restore_checking(struct fpu *fpu)
 
 static inline int restore_fpu_checking(struct task_struct *tsk)
 {
-	/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
-	   is pending.  Clear the x87 state here by setting it to fixed
-	   values. "m" is a random variable that should be in L1 */
-	alternative_input(
-		ASM_NOP8 ASM_NOP2,
-		"emms\n\t"	  	/* clear stack tags */
-		"fildl %P[addr]",	/* set F?P to defined value */
-		X86_FEATURE_FXSAVE_LEAK,
-		[addr] "m" (tsk->thread.fpu.has_fpu));
-
 	return fpu_restore_checking(&tsk->thread.fpu);
 }
 
@@ -290,21 +279,19 @@ static inline int restore_fpu_checking(struct task_struct *tsk)
  */
 static inline int __thread_has_fpu(struct task_struct *tsk)
 {
-	return tsk->thread.fpu.has_fpu;
+	return tsk->thread.has_fpu;
 }
 
 /* Must be paired with an 'stts' after! */
 static inline void __thread_clear_has_fpu(struct task_struct *tsk)
 {
-	tsk->thread.fpu.has_fpu = 0;
-	percpu_write(fpu_owner_task, NULL);
+	tsk->thread.has_fpu = 0;
 }
 
 /* Must be paired with a 'clts' before! */
 static inline void __thread_set_has_fpu(struct task_struct *tsk)
 {
-	tsk->thread.fpu.has_fpu = 1;
-	percpu_write(fpu_owner_task, tsk);
+	tsk->thread.has_fpu = 1;
 }
 
 /*
@@ -349,36 +336,30 @@ typedef struct { int preload; } fpu_switch_t;
  * We don't do that yet, so "fpu_lazy_restore()" always returns
  * false, but some day..
  */
-static inline int fpu_lazy_restore(struct task_struct *new, unsigned int cpu)
-{
-	return new == percpu_read_stable(fpu_owner_task) &&
-		cpu == new->thread.fpu.last_cpu;
-}
+#define fpu_lazy_restore(tsk) (0)
+#define fpu_lazy_state_intact(tsk) do { } while (0)
 
-static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct task_struct *new, int cpu)
+static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct task_struct *new)
 {
 	fpu_switch_t fpu;
 
 	fpu.preload = tsk_used_math(new) && new->fpu_counter > 5;
 	if (__thread_has_fpu(old)) {
-		if (!__save_init_fpu(old))
-			cpu = ~0;
-		old->thread.fpu.last_cpu = cpu;
-		old->thread.fpu.has_fpu = 0;	/* But leave fpu_owner_task! */
+		if (__save_init_fpu(old))
+			fpu_lazy_state_intact(old);
+		__thread_clear_has_fpu(old);
+		old->fpu_counter++;
 
 		/* Don't change CR0.TS if we just switch! */
 		if (fpu.preload) {
-			new->fpu_counter++;
 			__thread_set_has_fpu(new);
 			prefetch(new->thread.fpu.state);
 		} else
 			stts();
 	} else {
 		old->fpu_counter = 0;
-		old->thread.fpu.last_cpu = ~0;
 		if (fpu.preload) {
-			new->fpu_counter++;
-			if (fpu_lazy_restore(new, cpu))
+			if (fpu_lazy_restore(new))
 				fpu.preload = 0;
 			else
 				prefetch(new->thread.fpu.state);
@@ -396,10 +377,8 @@ static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct ta
  */
 static inline void switch_fpu_finish(struct task_struct *new, fpu_switch_t fpu)
 {
-	if (fpu.preload) {
-		if (unlikely(restore_fpu_checking(new)))
-			__thread_fpu_end(new);
-	}
+	if (fpu.preload)
+		__math_state_restore(new);
 }
 
 /*
@@ -472,10 +451,8 @@ static inline void kernel_fpu_begin(void)
 		__save_init_fpu(me);
 		__thread_clear_has_fpu(me);
 		/* We do 'stts()' in kernel_fpu_end() */
-	} else {
-		percpu_write(fpu_owner_task, NULL);
+	} else
 		clts();
-	}
 }
 
 static inline void kernel_fpu_end(void)

trunk/arch/x86/include/asm/processor.h

@@ -374,8 +374,6 @@ union thread_xstate {
 };
 
 struct fpu {
-	unsigned int last_cpu;
-	unsigned int has_fpu;
 	union thread_xstate *state;
 };
 
@@ -456,6 +454,7 @@ struct thread_struct {
 	unsigned long		trap_no;
 	unsigned long		error_code;
 	/* floating point and extended processor state */
+	unsigned long		has_fpu;
 	struct fpu		fpu;
 #ifdef CONFIG_X86_32
 	/* Virtual 86 mode info */

trunk/arch/x86/kernel/cpu/common.c

@@ -1044,8 +1044,6 @@ DEFINE_PER_CPU(char *, irq_stack_ptr) =
 
 DEFINE_PER_CPU(unsigned int, irq_count) = -1;
 
-DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
-
 /*
  * Special IST stacks which the CPU switches to when it calls
  * an IST-marked descriptor entry. Up to 7 stacks (hardware

trunk/arch/x86/kernel/process_32.c

@@ -214,7 +214,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 
 	task_user_gs(p) = get_user_gs(regs);
 
-	p->fpu_counter = 0;
 	p->thread.io_bitmap_ptr = NULL;
 	tsk = current;
 	err = -ENOMEM;
@@ -304,7 +303,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 
 	/* never put a printk in __switch_to... printk() calls wake_up*() indirectly */
 
-	fpu = switch_fpu_prepare(prev_p, next_p, cpu);
+	fpu = switch_fpu_prepare(prev_p, next_p);
 
 	/*
 	 * Reload esp0.

trunk/arch/x86/kernel/process_64.c

@@ -286,7 +286,6 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
 
 	set_tsk_thread_flag(p, TIF_FORK);
 
-	p->fpu_counter = 0;
 	p->thread.io_bitmap_ptr = NULL;
 
 	savesegment(gs, p->thread.gsindex);
@@ -389,7 +388,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	unsigned fsindex, gsindex;
 	fpu_switch_t fpu;
 
-	fpu = switch_fpu_prepare(prev_p, next_p, cpu);
+	fpu = switch_fpu_prepare(prev_p, next_p);
 
 	/*
 	 * Reload esp0, LDT and the page table pointer:

trunk/arch/x86/kernel/traps.c

@@ -570,6 +570,37 @@ asmlinkage void __attribute__((weak)) smp_threshold_interrupt(void)
 {
 }
 
+/*
+ * This gets called with the process already owning the
+ * FPU state, and with CR0.TS cleared. It just needs to
+ * restore the FPU register state.
+ */
+void __math_state_restore(struct task_struct *tsk)
+{
+	/* We need a safe address that is cheap to find and that is already
+	   in L1. We've just brought in "tsk->thread.has_fpu", so use that */
+#define safe_address (tsk->thread.has_fpu)
+
+	/* AMD K7/K8 CPUs don't save/restore FDP/FIP/FOP unless an exception
+	   is pending.  Clear the x87 state here by setting it to fixed
+	   values. safe_address is a random variable that should be in L1 */
+	alternative_input(
+		ASM_NOP8 ASM_NOP2,
+		"emms\n\t"	  	/* clear stack tags */
+		"fildl %P[addr]",	/* set F?P to defined value */
+		X86_FEATURE_FXSAVE_LEAK,
+		[addr] "m" (safe_address));
+
+	/*
+	 * Paranoid restore. send a SIGSEGV if we fail to restore the state.
+	 */
+	if (unlikely(restore_fpu_checking(tsk))) {
+		__thread_fpu_end(tsk);
+		force_sig(SIGSEGV, tsk);
+		return;
+	}
+}
+
 /*
  * 'math_state_restore()' saves the current math information in the
  * old math state array, and gets the new ones from the current task
@@ -600,14 +631,7 @@ void math_state_restore(void)
 	}
 
 	__thread_fpu_begin(tsk);
-	/*
-	 * Paranoid restore. send a SIGSEGV if we fail to restore the state.
-	 */
-	if (unlikely(restore_fpu_checking(tsk))) {
-		__thread_fpu_end(tsk);
-		force_sig(SIGSEGV, tsk);
-		return;
-	}
+	__math_state_restore(tsk);
 
 	tsk->fpu_counter++;
 }

trunk/include/linux/digsig.h

@@ -30,15 +30,15 @@ enum digest_algo {
 
 struct pubkey_hdr {
 	uint8_t		version;	/* key format version */
-	time_t		timestamp;	/* key made, always 0 for now */
+	uint32_t	timestamp;	/* key made, always 0 for now */
 	uint8_t		algo;
 	uint8_t		nmpi;
 	char		mpi[0];
 } __packed;
 
 struct signature_hdr {
 	uint8_t		version;	/* signature format version */
-	time_t		timestamp;	/* signature made */
+	uint32_t	timestamp;	/* signature made */
 	uint8_t		algo;
 	uint8_t		hash;
 	uint8_t		keyid[8];