Merge branch 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm

Pull ARM fixes from Russell King:
"This resolves some further issues with the dma mask changes on ARM
which have been found by TI and others, and also some corner cases
with the updates to the virtual to physical address translations.

Konstantin also found some problems with the unwinder, which now
performs tighter verification that the stack is valid while unwinding"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
ARM: fix asm/memory.h build error
ARM: 7917/1: cacheflush: correctly limit range of memory region being flushed
ARM: 7913/1: fix framepointer check in unwind_frame
ARM: 7912/1: check stack pointer in get_wchan
ARM: 7909/1: mm: Call setup_dma_zone() post early_paging_init()
ARM: 7908/1: mm: Fix the arm_dma_limit calculation
ARM: another fix for the DMA mapping checks

arch/arm/include/asm/memory.h

···
 #define TASK_UNMAPPED_BASE	UL(0x00000000)
 #endif
 
-#ifndef PHYS_OFFSET
-#define PHYS_OFFSET 		UL(CONFIG_DRAM_BASE)
-#endif
-
 #ifndef END_MEM
 #define END_MEM     		(UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE)
 #endif
 
 #ifndef PAGE_OFFSET
-#define PAGE_OFFSET		(PHYS_OFFSET)
+#define PAGE_OFFSET		PLAT_PHYS_OFFSET
 #endif
 
 /*
  * The module can be at any place in ram in nommu mode.
  */
 #define MODULES_END		(END_MEM)
-#define MODULES_VADDR		(PHYS_OFFSET)
+#define MODULES_VADDR		PAGE_OFFSET
 
 #define XIP_VIRT_ADDR(physaddr)  (physaddr)
 
···
 #define ARCH_PGD_SHIFT		0
 #endif
 #define ARCH_PGD_MASK		((1 << ARCH_PGD_SHIFT) - 1)
+
+/*
+ * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical
+ * memory.  This is used for XIP and NoMMU kernels, or by kernels which
+ * have their own mach/memory.h.  Assembly code must always use
+ * PLAT_PHYS_OFFSET and not PHYS_OFFSET.
+ */
+#ifndef PLAT_PHYS_OFFSET
+#define PLAT_PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
+#endif
 
 #ifndef __ASSEMBLY__
 
···
 
 #else
 
+#define PHYS_OFFSET	PLAT_PHYS_OFFSET
+
 static inline phys_addr_t __virt_to_phys(unsigned long x)
 {
 	return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET;
···
 
 #endif
 #endif
-#endif /* __ASSEMBLY__ */
-
-#ifndef PHYS_OFFSET
-#ifdef PLAT_PHYS_OFFSET
-#define PHYS_OFFSET	PLAT_PHYS_OFFSET
-#else
-#define PHYS_OFFSET	UL(CONFIG_PHYS_OFFSET)
-#endif
-#endif
-
-#ifndef __ASSEMBLY__
 
 /*
  * PFNs are used to describe any physical page; this means

arch/arm/kernel/head-nommu.S

···
 
 #ifdef CONFIG_ARM_MPU
 	/* Calculate the size of a region covering just the kernel */
-	ldr	r5, =PHYS_OFFSET		@ Region start: PHYS_OFFSET
+	ldr	r5, =PLAT_PHYS_OFFSET		@ Region start: PHYS_OFFSET
 	ldr     r6, =(_end)			@ Cover whole kernel
 	sub	r6, r6, r5			@ Minimum size of region to map
 	clz	r6, r6				@ Region size must be 2^N...
···
 	set_region_nr r0, #MPU_RAM_REGION
 	isb
 	/* Full access from PL0, PL1, shared for CONFIG_SMP, cacheable */
-	ldr	r0, =PHYS_OFFSET		@ RAM starts at PHYS_OFFSET
+	ldr	r0, =PLAT_PHYS_OFFSET		@ RAM starts at PHYS_OFFSET
 	ldr	r5,=(MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL)
 
 	setup_region r0, r5, r6, MPU_DATA_SIDE	@ PHYS_OFFSET, shared, enabled

arch/arm/kernel/head.S

···
 	sub	r4, r3, r4			@ (PHYS_OFFSET - PAGE_OFFSET)
 	add	r8, r8, r4			@ PHYS_OFFSET
 #else
-	ldr	r8, =PHYS_OFFSET		@ always constant in this case
+	ldr	r8, =PLAT_PHYS_OFFSET		@ always constant in this case
 #endif
 
 	/*

arch/arm/kernel/process.c

···
 unsigned long get_wchan(struct task_struct *p)
 {
 	struct stackframe frame;
+	unsigned long stack_page;
 	int count = 0;
 	if (!p || p == current || p->state == TASK_RUNNING)
 		return 0;
···
 	frame.sp = thread_saved_sp(p);
 	frame.lr = 0;			/* recovered from the stack */
 	frame.pc = thread_saved_pc(p);
+	stack_page = (unsigned long)task_stack_page(p);
 	do {
-		int ret = unwind_frame(&frame);
-		if (ret < 0)
+		if (frame.sp < stack_page ||
+		    frame.sp >= stack_page + THREAD_SIZE ||
+		    unwind_frame(&frame) < 0)
 			return 0;
 		if (!in_sched_functions(frame.pc))
 			return frame.pc;

arch/arm/kernel/setup.c

···
 	machine_desc = mdesc;
 	machine_name = mdesc->name;
 
-	setup_dma_zone(mdesc);
-
 	if (mdesc->reboot_mode != REBOOT_HARD)
 		reboot_mode = mdesc->reboot_mode;
 
···
 	sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
 
 	early_paging_init(mdesc, lookup_processor_type(read_cpuid_id()));
+	setup_dma_zone(mdesc);
 	sanity_check_meminfo();
 	arm_memblock_init(&meminfo, mdesc);
 

arch/arm/kernel/stacktrace.c

···
 	high = ALIGN(low, THREAD_SIZE);
 
 	/* check current frame pointer is within bounds */
-	if (fp < (low + 12) || fp + 4 >= high)
+	if (fp < low + 12 || fp > high - 4)
 		return -EINVAL;
 
 	/* restore the registers from the stack frame */

arch/arm/kernel/traps.c

···
 __do_cache_op(unsigned long start, unsigned long end)
 {
 	int ret;
-	unsigned long chunk = PAGE_SIZE;
 
 	do {
+		unsigned long chunk = min(PAGE_SIZE, end - start);
+
 		if (signal_pending(current)) {
 			struct thread_info *ti = current_thread_info();
 

arch/arm/mm/dma-mapping.c

···
 };
 EXPORT_SYMBOL(arm_coherent_dma_ops);
 
+static int __dma_supported(struct device *dev, u64 mask, bool warn)
+{
+	unsigned long max_dma_pfn;
+
+	/*
+	 * If the mask allows for more memory than we can address,
+	 * and we actually have that much memory, then we must
+	 * indicate that DMA to this device is not supported.
+	 */
+	if (sizeof(mask) != sizeof(dma_addr_t) &&
+	    mask > (dma_addr_t)~0 &&
+	    dma_to_pfn(dev, ~0) < max_pfn) {
+		if (warn) {
+			dev_warn(dev, "Coherent DMA mask %#llx is larger than dma_addr_t allows\n",
+				 mask);
+			dev_warn(dev, "Driver did not use or check the return value from dma_set_coherent_mask()?\n");
+		}
+		return 0;
+	}
+
+	max_dma_pfn = min(max_pfn, arm_dma_pfn_limit);
+
+	/*
+	 * Translate the device's DMA mask to a PFN limit.  This
+	 * PFN number includes the page which we can DMA to.
+	 */
+	if (dma_to_pfn(dev, mask) < max_dma_pfn) {
+		if (warn)
+			dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n",
+				 mask,
+				 dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1,
+				 max_dma_pfn + 1);
+		return 0;
+	}
+
+	return 1;
+}
+
 static u64 get_coherent_dma_mask(struct device *dev)
 {
 	u64 mask = (u64)DMA_BIT_MASK(32);
 
 	if (dev) {
-		unsigned long max_dma_pfn;
-
 		mask = dev->coherent_dma_mask;
 
 		/*
···
 			return 0;
 		}
 
-		max_dma_pfn = min(max_pfn, arm_dma_pfn_limit);
-
-		/*
-		 * If the mask allows for more memory than we can address,
-		 * and we actually have that much memory, then fail the
-		 * allocation.
-		 */
-		if (sizeof(mask) != sizeof(dma_addr_t) &&
-		    mask > (dma_addr_t)~0 &&
-		    dma_to_pfn(dev, ~0) > max_dma_pfn) {
-			dev_warn(dev, "Coherent DMA mask %#llx is larger than dma_addr_t allows\n",
-				 mask);
-			dev_warn(dev, "Driver did not use or check the return value from dma_set_coherent_mask()?\n");
+		if (!__dma_supported(dev, mask, true))
 			return 0;
-		}
-
-		/*
-		 * Now check that the mask, when translated to a PFN,
-		 * fits within the allowable addresses which we can
-		 * allocate.
-		 */
-		if (dma_to_pfn(dev, mask) < max_dma_pfn) {
-			dev_warn(dev, "Coherent DMA mask %#llx (pfn %#lx-%#lx) covers a smaller range of system memory than the DMA zone pfn 0x0-%#lx\n",
-				 mask,
-				 dma_to_pfn(dev, 0), dma_to_pfn(dev, mask) + 1,
-				 arm_dma_pfn_limit + 1);
-			return 0;
-		}
 	}
 
 	return mask;
···
  */
 int dma_supported(struct device *dev, u64 mask)
 {
-	unsigned long limit;
-
-	/*
-	 * If the mask allows for more memory than we can address,
-	 * and we actually have that much memory, then we must
-	 * indicate that DMA to this device is not supported.
-	 */
-	if (sizeof(mask) != sizeof(dma_addr_t) &&
-	    mask > (dma_addr_t)~0 &&
-	    dma_to_pfn(dev, ~0) > arm_dma_pfn_limit)
-		return 0;
-
-	/*
-	 * Translate the device's DMA mask to a PFN limit.  This
-	 * PFN number includes the page which we can DMA to.
-	 */
-	limit = dma_to_pfn(dev, mask);
-
-	if (limit < arm_dma_pfn_limit)
-		return 0;
-
-	return 1;
+	return __dma_supported(dev, mask, false);
 }
 EXPORT_SYMBOL(dma_supported);
 

arch/arm/mm/init.c

···
 #ifdef CONFIG_ZONE_DMA
 	if (mdesc->dma_zone_size) {
 		arm_dma_zone_size = mdesc->dma_zone_size;
-		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
+		arm_dma_limit = __pv_phys_offset + arm_dma_zone_size - 1;
 	} else
 		arm_dma_limit = 0xffffffff;
 	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;