Commit ca24a145 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm 

Pull two ARM fixes from Russell King:
 "It's been fairly quiet with the fixes.  Just two this time.  One fixes
  a long standing problem with KALLSYMS needing an additional pass, and
  the other sorts a problem with the vmalloc space interacting with
  static IO mappings."

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7438/1: fill possible PMD empty section gaps
  ARM: 7428/1: Prevent KALLSYM size mismatch on ARM.
parents 6887a413 19b52abe

arch/arm/kernel/vmlinux.lds.S

+2 −0
Original line number Diff line number Diff line
@@ -183,7 +183,9 @@ SECTIONS 
	}

#endif



#ifdef CONFIG_SMP

	PERCPU_SECTION(L1_CACHE_BYTES)

#endif



#ifdef CONFIG_XIP_KERNEL

	__data_loc = ALIGN(4);		/* location in binary */

arch/arm/mm/mmu.c

+74 −0
Original line number Diff line number Diff line
@@ -791,6 +791,79 @@ void __init iotable_init(struct map_desc *io_desc, int nr) 
	}

}



#ifndef CONFIG_ARM_LPAE



/*

 * The Linux PMD is made of two consecutive section entries covering 2MB

 * (see definition in include/asm/pgtable-2level.h).  However a call to

 * create_mapping() may optimize static mappings by using individual

 * 1MB section mappings.  This leaves the actual PMD potentially half

 * initialized if the top or bottom section entry isn't used, leaving it

 * open to problems if a subsequent ioremap() or vmalloc() tries to use

 * the virtual space left free by that unused section entry.

 *

 * Let's avoid the issue by inserting dummy vm entries covering the unused

 * PMD halves once the static mappings are in place.

 */



static void __init pmd_empty_section_gap(unsigned long addr)

{

	struct vm_struct *vm;



	vm = early_alloc_aligned(sizeof(*vm), __alignof__(*vm));

	vm->addr = (void *)addr;

	vm->size = SECTION_SIZE;

	vm->flags = VM_IOREMAP | VM_ARM_STATIC_MAPPING;

	vm->caller = pmd_empty_section_gap;

	vm_area_add_early(vm);

}



static void __init fill_pmd_gaps(void)

{

	struct vm_struct *vm;

	unsigned long addr, next = 0;

	pmd_t *pmd;



	/* we're still single threaded hence no lock needed here */

	for (vm = vmlist; vm; vm = vm->next) {

		if (!(vm->flags & VM_ARM_STATIC_MAPPING))

			continue;

		addr = (unsigned long)vm->addr;

		if (addr < next)

			continue;



		/*

		 * Check if this vm starts on an odd section boundary.

		 * If so and the first section entry for this PMD is free

		 * then we block the corresponding virtual address.

		 */

		if ((addr & ~PMD_MASK) == SECTION_SIZE) {

			pmd = pmd_off_k(addr);

			if (pmd_none(*pmd))

				pmd_empty_section_gap(addr & PMD_MASK);

		}



		/*

		 * Then check if this vm ends on an odd section boundary.

		 * If so and the second section entry for this PMD is empty

		 * then we block the corresponding virtual address.

		 */

		addr += vm->size;

		if ((addr & ~PMD_MASK) == SECTION_SIZE) {

			pmd = pmd_off_k(addr) + 1;

			if (pmd_none(*pmd))

				pmd_empty_section_gap(addr);

		}



		/* no need to look at any vm entry until we hit the next PMD */

		next = (addr + PMD_SIZE - 1) & PMD_MASK;

	}

}



#else

#define fill_pmd_gaps() do { } while (0)

#endif



static void * __initdata vmalloc_min =

	(void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
@@ -1072,6 +1145,7 @@ static void __init devicemaps_init(struct machine_desc *mdesc) 
	 */

	if (mdesc->map_io)

		mdesc->map_io();

	fill_pmd_gaps();



	/*

	 * Finally flush the caches and tlb to ensure that we're in a

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