Merge branch 'kexec/idmap' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into devel-stable

arch/arm/kernel/head.S

@@ -170,11 +170,11 @@ __create_page_tables:
 	 * Create identity mapping to cater for __enable_mmu.
 	 * This identity mapping will be removed by paging_init().
 	 */
-	adr	r0, __enable_mmu_loc
+	adr	r0, __turn_mmu_on_loc
 	ldmia	r0, {r3, r5, r6}
 	sub	r0, r0, r3			@ virt->phys offset
-	add	r5, r5, r0			@ phys __enable_mmu
-	add	r6, r6, r0			@ phys __enable_mmu_end
+	add	r5, r5, r0			@ phys __turn_mmu_on
+	add	r6, r6, r0			@ phys __turn_mmu_on_end
 	mov	r5, r5, lsr #SECTION_SHIFT
 	mov	r6, r6, lsr #SECTION_SHIFT
 
@@ -287,10 +287,10 @@ __create_page_tables:
 ENDPROC(__create_page_tables)
 	.ltorg
 	.align
-__enable_mmu_loc:
+__turn_mmu_on_loc:
 	.long	.
-	.long	__enable_mmu
-	.long	__enable_mmu_end
+	.long	__turn_mmu_on
+	.long	__turn_mmu_on_end
 
 #if defined(CONFIG_SMP)
 	__CPUINIT
@@ -398,15 +398,17 @@ ENDPROC(__enable_mmu)
  * other registers depend on the function called upon completion
  */
 	.align	5
-__turn_mmu_on:
+	.pushsection	.idmap.text, "ax"
+ENTRY(__turn_mmu_on)
 	mov	r0, r0
 	mcr	p15, 0, r0, c1, c0, 0		@ write control reg
 	mrc	p15, 0, r3, c0, c0, 0		@ read id reg
 	mov	r3, r3
 	mov	r3, r13
 	mov	pc, r3
-__enable_mmu_end:
+__turn_mmu_on_end:
 ENDPROC(__turn_mmu_on)
+	.popsection
 
 
 #ifdef CONFIG_SMP_ON_UP

arch/arm/kernel/sleep.S

@@ -54,6 +54,7 @@ ENDPROC(cpu_suspend_abort)
  * r0 = control register value
  */
 	.align	5
+	.pushsection	.idmap.text,"ax"
 ENTRY(cpu_resume_mmu)
 	ldr	r3, =cpu_resume_after_mmu
 	mcr	p15, 0, r0, c1, c0, 0	@ turn on MMU, I-cache, etc
@@ -62,6 +63,7 @@ ENTRY(cpu_resume_mmu)
 	mov	r0, r0
 	mov	pc, r3			@ jump to virtual address
 ENDPROC(cpu_resume_mmu)
+	.popsection
 cpu_resume_after_mmu:
 	bl	cpu_init		@ restore the und/abt/irq banked regs
 	mov	r0, #0			@ return zero on success

arch/arm/kernel/smp.c

@@ -31,6 +31,7 @@
 #include <asm/cpu.h>
 #include <asm/cputype.h>
 #include <asm/exception.h>
+#include <asm/idmap.h>
 #include <asm/topology.h>
 #include <asm/mmu_context.h>
 #include <asm/pgtable.h>
@@ -61,7 +62,6 @@ int __cpuinit __cpu_up(unsigned int cpu)
 {
 	struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu);
 	struct task_struct *idle = ci->idle;
-	pgd_t *pgd;
 	int ret;
 
 	/*
@@ -83,30 +83,12 @@ int __cpuinit __cpu_up(unsigned int cpu)
 		init_idle(idle, cpu);
 	}
 
-	/*
-	 * Allocate initial page tables to allow the new CPU to
-	 * enable the MMU safely.  This essentially means a set
-	 * of our "standard" page tables, with the addition of
-	 * a 1:1 mapping for the physical address of the kernel.
-	 */
-	pgd = pgd_alloc(&init_mm);
-	if (!pgd)
-		return -ENOMEM;
-
-	if (PHYS_OFFSET != PAGE_OFFSET) {
-#ifndef CONFIG_HOTPLUG_CPU
-		identity_mapping_add(pgd, __pa(__init_begin), __pa(__init_end));
-#endif
-		identity_mapping_add(pgd, __pa(_stext), __pa(_etext));
-		identity_mapping_add(pgd, __pa(_sdata), __pa(_edata));
-	}
-
 	/*
 	 * We need to tell the secondary core where to find
 	 * its stack and the page tables.
 	 */
 	secondary_data.stack = task_stack_page(idle) + THREAD_START_SP;
-	secondary_data.pgdir = virt_to_phys(pgd);
+	secondary_data.pgdir = virt_to_phys(idmap_pgd);
 	secondary_data.swapper_pg_dir = virt_to_phys(swapper_pg_dir);
 	__cpuc_flush_dcache_area(&secondary_data, sizeof(secondary_data));
 	outer_clean_range(__pa(&secondary_data), __pa(&secondary_data + 1));
@@ -142,16 +124,6 @@ int __cpuinit __cpu_up(unsigned int cpu)
 	secondary_data.stack = NULL;
 	secondary_data.pgdir = 0;
 
-	if (PHYS_OFFSET != PAGE_OFFSET) {
-#ifndef CONFIG_HOTPLUG_CPU
-		identity_mapping_del(pgd, __pa(__init_begin), __pa(__init_end));
-#endif
-		identity_mapping_del(pgd, __pa(_stext), __pa(_etext));
-		identity_mapping_del(pgd, __pa(_sdata), __pa(_edata));
-	}
-
-	pgd_free(&init_mm, pgd);
-
 	return ret;
 }
 

arch/arm/kernel/suspend.c

@@ -1,13 +1,12 @@
 #include <linux/init.h>
 
+#include <asm/idmap.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
 #include <asm/memory.h>
 #include <asm/suspend.h>
 #include <asm/tlbflush.h>
 
-static pgd_t *suspend_pgd;
-
 extern int __cpu_suspend(unsigned long, int (*)(unsigned long));
 extern void cpu_resume_mmu(void);
 
@@ -21,7 +20,7 @@ void __cpu_suspend_save(u32 *ptr, u32 ptrsz, u32 sp, u32 *save_ptr)
 	*save_ptr = virt_to_phys(ptr);
 
 	/* This must correspond to the LDM in cpu_resume() assembly */
-	*ptr++ = virt_to_phys(suspend_pgd);
+	*ptr++ = virt_to_phys(idmap_pgd);
 	*ptr++ = sp;
 	*ptr++ = virt_to_phys(cpu_do_resume);
 
@@ -42,7 +41,7 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
 	struct mm_struct *mm = current->active_mm;
 	int ret;
 
-	if (!suspend_pgd)
+	if (!idmap_pgd)
 		return -EINVAL;
 
 	/*
@@ -59,14 +58,3 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
 
 	return ret;
 }
-
-static int __init cpu_suspend_init(void)
-{
-	suspend_pgd = pgd_alloc(&init_mm);
-	if (suspend_pgd) {
-		unsigned long addr = virt_to_phys(cpu_resume_mmu);
-		identity_mapping_add(suspend_pgd, addr, addr + SECTION_SIZE);
-	}
-	return suspend_pgd ? 0 : -ENOMEM;
-}
-core_initcall(cpu_suspend_init);

arch/arm/kernel/vmlinux.lds.S

@@ -13,6 +13,12 @@
 	*(.proc.info.init)						\
 	VMLINUX_SYMBOL(__proc_info_end) = .;
 
+#define IDMAP_TEXT							\
+	ALIGN_FUNCTION();						\
+	VMLINUX_SYMBOL(__idmap_text_start) = .;				\
+	*(.idmap.text)							\
+	VMLINUX_SYMBOL(__idmap_text_end) = .;
+
 #ifdef CONFIG_HOTPLUG_CPU
 #define ARM_CPU_DISCARD(x)
 #define ARM_CPU_KEEP(x)		x
@@ -92,6 +98,7 @@ SECTIONS
 			SCHED_TEXT
 			LOCK_TEXT
 			KPROBES_TEXT
+			IDMAP_TEXT
 #ifdef CONFIG_MMU
 			*(.fixup)
 #endif