Index: stable/11/sys/arm64/arm64/swtch.S
===================================================================
--- stable/11/sys/arm64/arm64/swtch.S	(revision 317146)
+++ stable/11/sys/arm64/arm64/swtch.S	(revision 317147)
@@ -1,319 +1,318 @@
 /*-
  * Copyright (c) 2014 Andrew Turner
  * Copyright (c) 2014 The FreeBSD Foundation
  * All rights reserved.
  *
  * This software was developed by Andrew Turner under sponsorship from
  * the FreeBSD Foundation.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  */
 
 #include "assym.s"
 #include "opt_kstack_pages.h"
 #include "opt_sched.h"
 
 #include <machine/asm.h>
 
 __FBSDID("$FreeBSD$");
 
 .macro clear_step_flag pcbflags, tmp
 	tbz	\pcbflags, #PCB_SINGLE_STEP_SHIFT, 999f
 	mrs	\tmp, mdscr_el1
 	bic	\tmp, \tmp, #1
 	msr	mdscr_el1, \tmp
 	isb
 999:
 .endm
 
 .macro set_step_flag pcbflags, tmp
 	tbz	\pcbflags, #PCB_SINGLE_STEP_SHIFT, 999f
 	mrs	\tmp, mdscr_el1
 	orr	\tmp, \tmp, #1
 	msr	mdscr_el1, \tmp
 	isb
 999:
 .endm
 
 /*
  * void cpu_throw(struct thread *old, struct thread *new)
  */
 ENTRY(cpu_throw)
 	/* Of old == NULL skip disabling stepping */
 	cbz	x0, 1f
 
 	/* If we were single stepping, disable it */
 	ldr	x4, [x0, #TD_PCB]
 	ldr	w5, [x4, #PCB_FLAGS]
 	clear_step_flag w5, x6
 1:
 
 #ifdef VFP
 	/* Backup the new thread pointer around a call to C code */
 	mov	x19, x1
 	bl	vfp_discard
 	mov	x1, x19
 #endif
 
 	/* Store the new curthread */
 	str	x1, [x18, #PC_CURTHREAD]
 	/* And the new pcb */
 	ldr	x4, [x1, #TD_PCB]
 	str	x4, [x18, #PC_CURPCB]
 
 	/*
 	 * TODO: We may need to flush the cache here.
 	 */
 
 	/* Switch to the new pmap */
 	ldr	x5, [x4, #PCB_L0ADDR]
 	msr	ttbr0_el1, x5
 	isb
 
 	/* Invalidate the TLB */
 	dsb	sy
 	tlbi	vmalle1is
 	dsb	sy
 	isb
 
 	/* If we are single stepping, enable it */
 	ldr	w5, [x4, #PCB_FLAGS]
 	set_step_flag w5, x6
 
 	/* Restore the registers */
 	ldp	x5, x6, [x4, #PCB_SP]
 	mov	sp, x5
 	msr	tpidr_el0, x6
 	ldp	x8, x9, [x4, #PCB_REGS + 8 * 8]
 	ldp	x10, x11, [x4, #PCB_REGS + 10 * 8]
 	ldp	x12, x13, [x4, #PCB_REGS + 12 * 8]
 	ldp	x14, x15, [x4, #PCB_REGS + 14 * 8]
 	ldp	x16, x17, [x4, #PCB_REGS + 16 * 8]
 	ldr	     x19, [x4, #PCB_REGS + 19 * 8]
 	ldp	x20, x21, [x4, #PCB_REGS + 20 * 8]
 	ldp	x22, x23, [x4, #PCB_REGS + 22 * 8]
 	ldp	x24, x25, [x4, #PCB_REGS + 24 * 8]
 	ldp	x26, x27, [x4, #PCB_REGS + 26 * 8]
 	ldp	x28, x29, [x4, #PCB_REGS + 28 * 8]
 	ldr	x30, [x4, #PCB_REGS + 30 * 8]
 
 	ret
 END(cpu_throw)
 
 /*
  * void cpu_switch(struct thread *old, struct thread *new, struct mtx *mtx)
  *
  * x0 = old
  * x1 = new
  * x2 = mtx
  * x3 to x7, x16 and x17 are caller saved
  */
 ENTRY(cpu_switch)
 	/*
 	 * Save the old context.
 	 */
 	ldr	x4, [x0, #TD_PCB]
 
 	/* Store the callee-saved registers */
 	stp	x8, x9, [x4, #PCB_REGS + 8 * 8]
 	stp	x10, x11, [x4, #PCB_REGS + 10 * 8]
 	stp	x12, x13, [x4, #PCB_REGS + 12 * 8]
 	stp	x14, x15, [x4, #PCB_REGS + 14 * 8]
 	stp	x16, x17, [x4, #PCB_REGS + 16 * 8]
 	stp	x18, x19, [x4, #PCB_REGS + 18 * 8]
 	stp	x20, x21, [x4, #PCB_REGS + 20 * 8]
 	stp	x22, x23, [x4, #PCB_REGS + 22 * 8]
 	stp	x24, x25, [x4, #PCB_REGS + 24 * 8]
 	stp	x26, x27, [x4, #PCB_REGS + 26 * 8]
 	stp	x28, x29, [x4, #PCB_REGS + 28 * 8]
 	str	x30, [x4, #PCB_REGS + 30 * 8]
 	/* And the old stack pointer */
 	mov	x5, sp
 	mrs	x6, tpidr_el0
 	stp	x5, x6, [x4, #PCB_SP]
 
 	/* If we were single stepping, disable it */
 	ldr	w5, [x4, #PCB_FLAGS]
 	clear_step_flag w5, x6
 
 #ifdef VFP
 	mov	x19, x0
 	mov	x20, x1
 	mov	x21, x2
 	/* Load the pcb address */
 	mov	x1, x4
 	bl	vfp_save_state
 	mov	x2, x21
 	mov	x1, x20
 	mov	x0, x19
 #endif
 
 	/* Store the new curthread */
 	str	x1, [x18, #PC_CURTHREAD]
 
 	/*
 	 * Restore the saved context and set it as curpcb.
 	 */
 	ldr	x4, [x1, #TD_PCB]
 	str	x4, [x18, #PC_CURPCB]
 
 	/*
 	 * TODO: We may need to flush the cache here if switching
 	 * to a user process.
 	 */
 
 	/* Switch to the new pmap */
 	ldr	x5, [x4, #PCB_L0ADDR]
 	msr	ttbr0_el1, x5
 	isb
 
 	/* Invalidate the TLB */
 	dsb	sy
 	tlbi	vmalle1is
 	dsb	sy
 	isb
 
 	/*
 	 * Release the old thread. This doesn't need to be a store-release
 	 * as the above dsb instruction will provide release semantics.
 	 */
 	str	x2, [x0, #TD_LOCK]
 #if defined(SCHED_ULE) && defined(SMP)
 	/* Spin if TD_LOCK points to a blocked_lock */
 	ldr	x2, =_C_LABEL(blocked_lock)
 1:
 	ldar	x3, [x1, #TD_LOCK]
 	cmp	x3, x2
 	b.eq	1b
 #endif
 
 	/* If we are single stepping, enable it */
 	ldr	w5, [x4, #PCB_FLAGS]
 	set_step_flag w5, x6
 
 	/* Restore the registers */
 	ldp	x5, x6, [x4, #PCB_SP]
 	mov	sp, x5
 	msr	tpidr_el0, x6
 	ldp	x8, x9, [x4, #PCB_REGS + 8 * 8]
 	ldp	x10, x11, [x4, #PCB_REGS + 10 * 8]
 	ldp	x12, x13, [x4, #PCB_REGS + 12 * 8]
 	ldp	x14, x15, [x4, #PCB_REGS + 14 * 8]
 	ldp	x16, x17, [x4, #PCB_REGS + 16 * 8]
 	ldr	     x19, [x4, #PCB_REGS + 19 * 8]
 	ldp	x20, x21, [x4, #PCB_REGS + 20 * 8]
 	ldp	x22, x23, [x4, #PCB_REGS + 22 * 8]
 	ldp	x24, x25, [x4, #PCB_REGS + 24 * 8]
 	ldp	x26, x27, [x4, #PCB_REGS + 26 * 8]
 	ldp	x28, x29, [x4, #PCB_REGS + 28 * 8]
 	ldr	x30, [x4, #PCB_REGS + 30 * 8]
 
 	str	xzr, [x4, #PCB_REGS + 18 * 8]
 	ret
 .Lcpu_switch_panic_str:
 	.asciz "cpu_switch: %p\0"
 END(cpu_switch)
 
 ENTRY(fork_trampoline)
 	mov	x0, x8
 	mov	x1, x9
 	mov	x2, sp
 	mov	fp, #0	/* Stack traceback stops here. */
 	bl	_C_LABEL(fork_exit)
 
-	/* Restore sp and lr */
-	ldp	x0, x1, [sp]
-	msr	sp_el0, x0
-	mov	lr, x1
-
 	/* Restore the registers other than x0 and x1 */
 	ldp	x2, x3, [sp, #TF_X + 2 * 8]
 	ldp	x4, x5, [sp, #TF_X + 4 * 8]
 	ldp	x6, x7, [sp, #TF_X + 6 * 8]
 	ldp	x8, x9, [sp, #TF_X + 8 * 8]
 	ldp	x10, x11, [sp, #TF_X + 10 * 8]
 	ldp	x12, x13, [sp, #TF_X + 12 * 8]
 	ldp	x14, x15, [sp, #TF_X + 14 * 8]
 	ldp	x16, x17, [sp, #TF_X + 16 * 8]
 	ldr	     x19, [sp, #TF_X + 19 * 8]
 	ldp	x20, x21, [sp, #TF_X + 20 * 8]
 	ldp	x22, x23, [sp, #TF_X + 22 * 8]
 	ldp	x24, x25, [sp, #TF_X + 24 * 8]
 	ldp	x26, x27, [sp, #TF_X + 26 * 8]
 	ldp	x28, x29, [sp, #TF_X + 28 * 8]
-	/* Skip x30 as it was restored above as lr */
 
 	/*
 	 * Disable interrupts to avoid
-	 * overwriting spsr_el1 by an IRQ exception.
+	 * overwriting spsr_el1 and sp_el0 by an IRQ exception.
 	 */
 	msr	daifset, #2
+
+	/* Restore sp and lr */
+	ldp	x0, x1, [sp]
+	msr	sp_el0, x0
+	mov	lr, x1
 
 	/* Restore elr and spsr */
 	ldp	x0, x1, [sp, #16]
 	msr	elr_el1, x0
 	msr	spsr_el1, x1
 
 	/* Finally x0 and x1 */
 	ldp	x0, x1, [sp, #TF_X + 0 * 8]
 	ldr	x18, [sp, #TF_X + 18 * 8]
 
 	/*
 	 * No need for interrupts reenabling since PSR
 	 * will be set to the desired value anyway.
 	 */
 	eret
 	
 END(fork_trampoline)
 
 ENTRY(savectx)
 	/* Store the callee-saved registers */
 	stp	x8,  x9,  [x0, #PCB_REGS + 8 * 8]
 	stp	x10, x11, [x0, #PCB_REGS + 10 * 8]
 	stp	x12, x13, [x0, #PCB_REGS + 12 * 8]
 	stp	x14, x15, [x0, #PCB_REGS + 14 * 8]
 	stp	x16, x17, [x0, #PCB_REGS + 16 * 8]
 	stp	x18, x19, [x0, #PCB_REGS + 18 * 8]
 	stp	x20, x21, [x0, #PCB_REGS + 20 * 8]
 	stp	x22, x23, [x0, #PCB_REGS + 22 * 8]
 	stp	x24, x25, [x0, #PCB_REGS + 24 * 8]
 	stp	x26, x27, [x0, #PCB_REGS + 26 * 8]
 	stp	x28, x29, [x0, #PCB_REGS + 28 * 8]
 	str	x30, [x0, #PCB_REGS + 30 * 8]
 	/* And the old stack pointer */
 	mov	x5, sp
 	mrs	x6, tpidr_el0
 	stp	x5, x6, [x0, #PCB_SP]
 
 	/* Store the VFP registers */
 #ifdef VFP
 	mov	x28, lr
 	mov	x1, x0			/* move pcb to the correct register */
 	mov	x0, xzr			/* td = NULL */
 	bl	vfp_save_state
 	mov	lr, x28
 #endif
 
 	ret
 END(savectx)
 
Index: stable/11
===================================================================
--- stable/11	(revision 317146)
+++ stable/11	(revision 317147)

Property changes on: stable/11
___________________________________________________________________
Modified: svn:mergeinfo
## -0,0 +0,1 ##
   Merged /head:r313772