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

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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.
This commit is contained in:
Linus Torvalds 2012-07-01 11:02:25 -07:00
commit ca24a14557
2 changed files with 76 additions and 0 deletions
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2
arch/arm/kernel/vmlinux.lds.S
View File

@ -183,7 +183,9 @@ SECTIONS
} }
#endif #endif
#ifdef CONFIG_SMP
PERCPU_SECTION(L1_CACHE_BYTES) PERCPU_SECTION(L1_CACHE_BYTES)
#endif
#ifdef CONFIG_XIP_KERNEL #ifdef CONFIG_XIP_KERNEL
__data_loc = ALIGN(4); /* location in binary */ __data_loc = ALIGN(4); /* location in binary */

74
arch/arm/mm/mmu.c
View File

@ -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 = static void * __initdata vmalloc_min =
(void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET); (void *)(VMALLOC_END - (240 << 20) - VMALLOC_OFFSET);
@ -1072,6 +1145,7 @@ static void __init devicemaps_init(struct machine_desc *mdesc)
*/ */
if (mdesc->map_io) if (mdesc->map_io)
mdesc->map_io(); mdesc->map_io();
fill_pmd_gaps();
/* /*
* Finally flush the caches and tlb to ensure that we're in a * Finally flush the caches and tlb to ensure that we're in a