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-rw-r--r--arch/arm/mm/dma-mapping.c11
-rw-r--r--arch/arm/mm/idmap.c12
-rw-r--r--arch/arm/mm/mmu.c6
3 files changed, 25 insertions, 4 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 4c88935654c..1f88db06b13 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -461,12 +461,21 @@ void __init dma_contiguous_remap(void)
map.type = MT_MEMORY_DMA_READY;
/*
- * Clear previous low-memory mapping
+ * Clear previous low-memory mapping to ensure that the
+ * TLB does not see any conflicting entries, then flush
+ * the TLB of the old entries before creating new mappings.
+ *
+ * This ensures that any speculatively loaded TLB entries
+ * (even though they may be rare) can not cause any problems,
+ * and ensures that this code is architecturally compliant.
*/
for (addr = __phys_to_virt(start); addr < __phys_to_virt(end);
addr += PMD_SIZE)
pmd_clear(pmd_off_k(addr));
+ flush_tlb_kernel_range(__phys_to_virt(start),
+ __phys_to_virt(end));
+
iotable_init(&map, 1);
}
}
diff --git a/arch/arm/mm/idmap.c b/arch/arm/mm/idmap.c
index 8e0e52eb76b..c447ec70e86 100644
--- a/arch/arm/mm/idmap.c
+++ b/arch/arm/mm/idmap.c
@@ -9,6 +9,11 @@
#include <asm/sections.h>
#include <asm/system_info.h>
+/*
+ * Note: accesses outside of the kernel image and the identity map area
+ * are not supported on any CPU using the idmap tables as its current
+ * page tables.
+ */
pgd_t *idmap_pgd;
phys_addr_t (*arch_virt_to_idmap) (unsigned long x);
@@ -25,6 +30,13 @@ static void idmap_add_pmd(pud_t *pud, unsigned long addr, unsigned long end,
pr_warning("Failed to allocate identity pmd.\n");
return;
}
+ /*
+ * Copy the original PMD to ensure that the PMD entries for
+ * the kernel image are preserved.
+ */
+ if (!pud_none(*pud))
+ memcpy(pmd, pmd_offset(pud, 0),
+ PTRS_PER_PMD * sizeof(pmd_t));
pud_populate(&init_mm, pud, pmd);
pmd += pmd_index(addr);
} else
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index ab14b79b03f..6e3ba8d112a 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -1406,8 +1406,8 @@ void __init early_paging_init(const struct machine_desc *mdesc,
return;
/* remap kernel code and data */
- map_start = init_mm.start_code;
- map_end = init_mm.brk;
+ map_start = init_mm.start_code & PMD_MASK;
+ map_end = ALIGN(init_mm.brk, PMD_SIZE);
/* get a handle on things... */
pgd0 = pgd_offset_k(0);
@@ -1442,7 +1442,7 @@ void __init early_paging_init(const struct machine_desc *mdesc,
}
/* remap pmds for kernel mapping */
- phys = __pa(map_start) & PMD_MASK;
+ phys = __pa(map_start);
do {
*pmdk++ = __pmd(phys | pmdprot);
phys += PMD_SIZE;