ARM: fix booting low-vectors machines

Commit f6f91b0d9fd9 (ARM: allow kuser helpers to be removed from the
vector page) required two pages for the vectors code.  Although the
code setting up the initial page tables was updated, the code which
allocates page tables for new processes wasn't, neither was the code
which tears down the mappings.  Fix this.

Fixes: f6f91b0d9fd9 ("ARM: allow kuser helpers to be removed from the vector page")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: <stable@vger.kernel.org>

diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index be956dbf6baea3a7481baa11c58233d0741702d1..1571d126e9ddb08b77c99955538209212755ebfd 100644 (file)
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -61,7 +61,7 @@ extern void __pgd_error(const char *file, int line, pgd_t);
  * mapping to be mapped at.  This is particularly important for
  * non-high vector CPUs.
  */
-#define FIRST_USER_ADDRESS     PAGE_SIZE
+#define FIRST_USER_ADDRESS     (PAGE_SIZE * 2)
 
 /*
  * Use TASK_SIZE as the ceiling argument for free_pgtables() and

diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index d27158c38eb0b190b869e028b93d8265fb90969e..5e85ed371364c17657be7d7155139a5e3f536437 100644 (file)
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -146,7 +146,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
 
        info.flags = VM_UNMAPPED_AREA_TOPDOWN;
        info.length = len;
-       info.low_limit = PAGE_SIZE;
+       info.low_limit = FIRST_USER_ADDRESS;
        info.high_limit = mm->mmap_base;
        info.align_mask = do_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
        info.align_offset = pgoff << PAGE_SHIFT;

diff --git a/arch/arm/mm/pgd.c b/arch/arm/mm/pgd.c
index 0acb089d0f70db818ce487fa67b0fb90b1b0b69d..1046b373d1aedb2823e3bb62f106681f9b63fc2a 100644 (file)
--- a/arch/arm/mm/pgd.c
+++ b/arch/arm/mm/pgd.c
@@ -87,7 +87,8 @@ pgd_t *pgd_alloc(struct mm_struct *mm)
                init_pud = pud_offset(init_pgd, 0);
                init_pmd = pmd_offset(init_pud, 0);
                init_pte = pte_offset_map(init_pmd, 0);
-               set_pte_ext(new_pte, *init_pte, 0);
+               set_pte_ext(new_pte + 0, init_pte[0], 0);
+               set_pte_ext(new_pte + 1, init_pte[1], 0);
                pte_unmap(init_pte);
                pte_unmap(new_pte);
        }