Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

Pull two sparc fixes from David Miller:

 1) Fix boots with gcc-4.9 compiled sparc64 kernels.

 2) Add missing __get_user_pages_fast() on sparc64 to fix hangs on
    futexes used in transparent hugepage areas.

    It's really idiotic to have a weak symbolled fallback that just
    returns zero, and causes this kind of bug.  There should be no
    backup implementation and the link should fail if the architecture
    fails to provide __get_user_pages_fast() and supports transparent
    hugepages.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Implement __get_user_pages_fast().
  sparc64: Fix register corruption in top-most kernel stack frame during boot.

arch/sparc/include/asm/oplib_64.h

@@ -62,7 +62,8 @@ struct linux_mem_p1275 {
 /* You must call prom_init() before using any of the library services,
  * preferably as early as possible.  Pass it the romvec pointer.
  */
-void prom_init(void *cif_handler, void *cif_stack);
+void prom_init(void *cif_handler);
+void prom_init_report(void);
 
 /* Boot argument acquisition, returns the boot command line string. */
 char *prom_getbootargs(void);

arch/sparc/include/asm/setup.h

@@ -48,6 +48,8 @@ unsigned long safe_compute_effective_address(struct pt_regs *, unsigned int);
 #endif
 
 #ifdef CONFIG_SPARC64
+void __init start_early_boot(void);
+
 /* unaligned_64.c */
 int handle_ldf_stq(u32 insn, struct pt_regs *regs);
 void handle_ld_nf(u32 insn, struct pt_regs *regs);

arch/sparc/kernel/entry.h

@@ -65,13 +65,10 @@ struct pause_patch_entry {
 extern struct pause_patch_entry __pause_3insn_patch,
 	__pause_3insn_patch_end;
 
-void __init per_cpu_patch(void);
 void sun4v_patch_1insn_range(struct sun4v_1insn_patch_entry *,
 			     struct sun4v_1insn_patch_entry *);
 void sun4v_patch_2insn_range(struct sun4v_2insn_patch_entry *,
 			     struct sun4v_2insn_patch_entry *);
-void __init sun4v_patch(void);
-void __init boot_cpu_id_too_large(int cpu);
 extern unsigned int dcache_parity_tl1_occurred;
 extern unsigned int icache_parity_tl1_occurred;
 

arch/sparc/kernel/head_64.S

@@ -672,14 +672,12 @@ tlb_fixup_done:
 	sethi	%hi(init_thread_union), %g6
 	or	%g6, %lo(init_thread_union), %g6
 	ldx	[%g6 + TI_TASK], %g4
-	mov	%sp, %l6
 
 	wr	%g0, ASI_P, %asi
 	mov	1, %g1
 	sllx	%g1, THREAD_SHIFT, %g1
 	sub	%g1, (STACKFRAME_SZ + STACK_BIAS), %g1
 	add	%g6, %g1, %sp
-	mov	0, %fp
 
 	/* Set per-cpu pointer initially to zero, this makes
 	 * the boot-cpu use the in-kernel-image per-cpu areas
@@ -706,44 +704,14 @@ tlb_fixup_done:
 	 nop
 #endif
 
-	mov	%l6, %o1			! OpenPROM stack
 	call	prom_init
 	 mov	%l7, %o0			! OpenPROM cif handler
 
-	/* Initialize current_thread_info()->cpu as early as possible.
-	 * In order to do that accurately we have to patch up the get_cpuid()
-	 * assembler sequences.  And that, in turn, requires that we know
-	 * if we are on a Starfire box or not.  While we're here, patch up
-	 * the sun4v sequences as well.
+	/* To create a one-register-window buffer between the kernel's
+	 * initial stack and the last stack frame we use from the firmware,
+	 * do the rest of the boot from a C helper function.
 	 */
-	call	check_if_starfire
-	 nop
-	call	per_cpu_patch
-	 nop
-	call	sun4v_patch
-	 nop
-
-#ifdef CONFIG_SMP
-	call	hard_smp_processor_id
-	 nop
-	cmp	%o0, NR_CPUS
-	blu,pt	%xcc, 1f
-	 nop
-	call	boot_cpu_id_too_large
-	 nop
-	/* Not reached... */
-
-1:
-#else
-	mov	0, %o0
-#endif
-	sth	%o0, [%g6 + TI_CPU]
-
-	call	prom_init_report
-	 nop
-
-	/* Off we go.... */
-	call	start_kernel
+	call	start_early_boot
 	 nop
 	/* Not reached... */
 

arch/sparc/kernel/hvtramp.S

@@ -109,7 +109,6 @@ hv_cpu_startup:
 	sllx		%g5, THREAD_SHIFT, %g5
 	sub		%g5, (STACKFRAME_SZ + STACK_BIAS), %g5
 	add		%g6, %g5, %sp
-	mov		0, %fp
 
 	call		init_irqwork_curcpu
 	 nop

arch/sparc/kernel/setup_64.c

@@ -30,6 +30,7 @@
 #include <linux/cpu.h>
 #include <linux/initrd.h>
 #include <linux/module.h>
+#include <linux/start_kernel.h>
 
 #include <asm/io.h>
 #include <asm/processor.h>
@@ -162,7 +163,7 @@ char reboot_command[COMMAND_LINE_SIZE];
 
 static struct pt_regs fake_swapper_regs = { { 0, }, 0, 0, 0, 0 };
 
-void __init per_cpu_patch(void)
+static void __init per_cpu_patch(void)
 {
 	struct cpuid_patch_entry *p;
 	unsigned long ver;
@@ -254,7 +255,7 @@ void sun4v_patch_2insn_range(struct sun4v_2insn_patch_entry *start,
 	}
 }
 
-void __init sun4v_patch(void)
+static void __init sun4v_patch(void)
 {
 	extern void sun4v_hvapi_init(void);
 
@@ -323,14 +324,25 @@ static void __init pause_patch(void)
 	}
 }
 
-#ifdef CONFIG_SMP
-void __init boot_cpu_id_too_large(int cpu)
+void __init start_early_boot(void)
 {
+	int cpu;
+
+	check_if_starfire();
+	per_cpu_patch();
+	sun4v_patch();
+
+	cpu = hard_smp_processor_id();
+	if (cpu >= NR_CPUS) {
 		prom_printf("Serious problem, boot cpu id (%d) >= NR_CPUS (%d)\n",
 			    cpu, NR_CPUS);
 		prom_halt();
+	}
+	current_thread_info()->cpu = cpu;
+
+	prom_init_report();
+	start_kernel();
 }
-#endif
 
 /* On Ultra, we support all of the v8 capabilities. */
 unsigned long sparc64_elf_hwcap = (HWCAP_SPARC_FLUSH | HWCAP_SPARC_STBAR |

arch/sparc/kernel/trampoline_64.S

@@ -109,10 +109,13 @@ startup_continue:
 	brnz,pn		%g1, 1b
 	 nop
 
-	sethi		%hi(p1275buf), %g2
-	or		%g2, %lo(p1275buf), %g2
-	ldx		[%g2 + 0x10], %l2
-	add		%l2, -(192 + 128), %sp
+	/* Get onto temporary stack which will be in the locked
+	 * kernel image.
+	 */
+	sethi		%hi(tramp_stack), %g1
+	or		%g1, %lo(tramp_stack), %g1
+	add		%g1, TRAMP_STACK_SIZE, %g1
+	sub		%g1, STACKFRAME_SZ + STACK_BIAS + 256, %sp
 	flushw
 
 	/* Setup the loop variables:
@@ -394,7 +397,6 @@ after_lock_tlb:
 	sllx		%g5, THREAD_SHIFT, %g5
 	sub		%g5, (STACKFRAME_SZ + STACK_BIAS), %g5
 	add		%g6, %g5, %sp
-	mov		0, %fp
 
 	rdpr		%pstate, %o1
 	or		%o1, PSTATE_IE, %o1

arch/sparc/mm/gup.c

@@ -160,6 +160,36 @@ static int gup_pud_range(pgd_t pgd, unsigned long addr, unsigned long end,
 	return 1;
 }
 
+int __get_user_pages_fast(unsigned long start, int nr_pages, int write,
+			  struct page **pages)
+{
+	struct mm_struct *mm = current->mm;
+	unsigned long addr, len, end;
+	unsigned long next, flags;
+	pgd_t *pgdp;
+	int nr = 0;
+
+	start &= PAGE_MASK;
+	addr = start;
+	len = (unsigned long) nr_pages << PAGE_SHIFT;
+	end = start + len;
+
+	local_irq_save(flags);
+	pgdp = pgd_offset(mm, addr);
+	do {
+		pgd_t pgd = *pgdp;
+
+		next = pgd_addr_end(addr, end);
+		if (pgd_none(pgd))
+			break;
+		if (!gup_pud_range(pgd, addr, next, write, pages, &nr))
+			break;
+	} while (pgdp++, addr = next, addr != end);
+	local_irq_restore(flags);
+
+	return nr;
+}
+
 int get_user_pages_fast(unsigned long start, int nr_pages, int write,
 			struct page **pages)
 {

arch/sparc/prom/cif.S

@@ -11,11 +11,10 @@
 	.text
 	.globl	prom_cif_direct
 prom_cif_direct:
+	save	%sp, -192, %sp
 	sethi	%hi(p1275buf), %o1
 	or	%o1, %lo(p1275buf), %o1
-	ldx	[%o1 + 0x0010], %o2	! prom_cif_stack
-	save	%o2, -192, %sp
-	ldx	[%i1 + 0x0008], %l2	! prom_cif_handler
+	ldx	[%o1 + 0x0008], %l2	! prom_cif_handler
 	mov	%g4, %l0
 	mov	%g5, %l1
 	mov	%g6, %l3

arch/sparc/prom/init_64.c

@@ -26,13 +26,13 @@ phandle prom_chosen_node;
  * It gets passed the pointer to the PROM vector.
  */
 
-extern void prom_cif_init(void *, void *);
+extern void prom_cif_init(void *);
 
-void __init prom_init(void *cif_handler, void *cif_stack)
+void __init prom_init(void *cif_handler)
 {
 	phandle node;
 
-	prom_cif_init(cif_handler, cif_stack);
+	prom_cif_init(cif_handler);
 
 	prom_chosen_node = prom_finddevice(prom_chosen_path);
 	if (!prom_chosen_node || (s32)prom_chosen_node == -1)

arch/sparc/prom/p1275.c

@@ -20,7 +20,6 @@
 struct {
 	long prom_callback;			/* 0x00 */
 	void (*prom_cif_handler)(long *);	/* 0x08 */
-	unsigned long prom_cif_stack;		/* 0x10 */
 } p1275buf;
 
 extern void prom_world(int);
@@ -52,5 +51,4 @@ void p1275_cmd_direct(unsigned long *args)
 void prom_cif_init(void *cif_handler, void *cif_stack)
 {
 	p1275buf.prom_cif_handler = (void (*)(long *))cif_handler;
-	p1275buf.prom_cif_stack = (unsigned long)cif_stack;
 }