Fix "scheduling while atomic" messages below do_anonymous_page when
CONFIG_HIGHPTE=y: must unmap and remap the page_table around page
allocation.  And let's shift the usual pte_unmap to the minor_fault exit.

Signed-off-by: Hugh Dickins <[EMAIL PROTECTED]>
---

Please don't interpret this fix as my approving the do_anonymous_page
without page_table_lock patches!  I'm still averse to this special
route with different locking rules; but let's get it right for testing.

 mm/memory.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

--- 2.6.13-rc3-mm3/mm/memory.c  2005-07-29 14:11:33.000000000 +0100
+++ linux/mm/memory.c   2005-07-29 20:58:54.000000000 +0100
@@ -1796,12 +1796,12 @@ do_anonymous_page(struct mm_struct *mm, 
                } else {
                        inc_page_state(cmpxchg_fail_anon_read);
                }
-               pte_unmap(page_table);
                goto minor_fault;
        }
 
        /* This leaves the write case */
        page_table_atomic_stop(mm);
+       pte_unmap(page_table);
        if (unlikely(anon_vma_prepare(vma)))
                goto oom;
 
@@ -1812,10 +1812,10 @@ do_anonymous_page(struct mm_struct *mm, 
        entry = maybe_mkwrite(pte_mkdirty(mk_pte(page,
                                                vma->vm_page_prot)),
                                vma);
+       page_table = pte_offset_map(pmd, addr);
        page_table_atomic_start(mm);
 
        if (!ptep_cmpxchg(mm, addr, page_table, orig_entry, entry)) {
-               pte_unmap(page_table);
                page_cache_release(page);
                inc_page_state(cmpxchg_fail_anon_write);
                goto minor_fault;
@@ -1829,12 +1829,12 @@ do_anonymous_page(struct mm_struct *mm, 
        page_add_anon_rmap(page, vma, addr);
        lru_cache_add_active(page);
        inc_mm_counter(mm, rss);
-       pte_unmap(page_table);
        update_mmu_cache(vma, addr, entry);
        lazy_mmu_prot_update(entry);
 
 minor_fault:
        page_table_atomic_stop(mm);
+       pte_unmap(page_table);
        return VM_FAULT_MINOR;
 
 oom:
-
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