From 7ef939054139ef857cebbec07cbd12d7cf7beedd Mon Sep 17 00:00:00 2001
From: Jeff Dike <jdike@addtoit.com>
Date: Sat, 3 Sep 2005 15:57:52 -0700
Subject: [PATCH] [PATCH] uml: fix x86_64 page leak
We were leaking pmd pages when 3_LEVEL_PGTABLES was enabled. This fixes that.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
arch/um/kernel/skas/include/mmu-skas.h | 4 ++++
arch/um/kernel/skas/mmu.c | 9 ++++++++-
include/asm-um/pgalloc.h | 12 +++++++-----
include/asm-um/pgtable-3level.h | 9 +++------
4 files changed, 22 insertions(+), 12 deletions(-)
diff --git a/arch/um/kernel/skas/include/mmu-skas.h b/arch/um/kernel/skas/include/mmu-skas.h
index 278b72f1d9ad..09536f81ee42 100644
--- a/arch/um/kernel/skas/include/mmu-skas.h
+++ b/arch/um/kernel/skas/include/mmu-skas.h
@@ -6,11 +6,15 @@
#ifndef __SKAS_MMU_H
#define __SKAS_MMU_H
+#include "linux/config.h"
#include "mm_id.h"
struct mmu_context_skas {
struct mm_id id;
unsigned long last_page_table;
+#ifdef CONFIG_3_LEVEL_PGTABLES
+ unsigned long last_pmd;
+#endif
};
extern void switch_mm_skas(struct mm_id * mm_idp);
diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index d837223e22af..240143b616a2 100644
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -56,6 +56,9 @@ static int init_stub_pte(struct mm_struct *mm, unsigned long proc,
*/
mm->context.skas.last_page_table = pmd_page_kernel(*pmd);
+#ifdef CONFIG_3_LEVEL_PGTABLES
+ mm->context.skas.last_pmd = (unsigned long) __va(pud_val(*pud));
+#endif
*pte = mk_pte(virt_to_page(kernel), __pgprot(_PAGE_PRESENT));
*pte = pte_mkexec(*pte);
@@ -144,6 +147,10 @@ void destroy_context_skas(struct mm_struct *mm)
if(!proc_mm || !ptrace_faultinfo){
free_page(mmu->id.stack);
- free_page(mmu->last_page_table);
+ pte_free_kernel((pte_t *) mmu->last_page_table);
+ dec_page_state(nr_page_table_pages);
+#ifdef CONFIG_3_LEVEL_PGTABLES
+ pmd_free((pmd_t *) mmu->last_pmd);
+#endif
}
}
diff --git a/include/asm-um/pgalloc.h b/include/asm-um/pgalloc.h
index 8fcb2fc0a892..ea49411236dc 100644
--- a/include/asm-um/pgalloc.h
+++ b/include/asm-um/pgalloc.h
@@ -42,11 +42,13 @@ static inline void pte_free(struct page *pte)
#define __pte_free_tlb(tlb,pte) tlb_remove_page((tlb),(pte))
#ifdef CONFIG_3_LEVEL_PGTABLES
-/*
- * In the 3-level case we free the pmds as part of the pgd.
- */
-#define pmd_free(x) do { } while (0)
-#define __pmd_free_tlb(tlb,x) do { } while (0)
+
+extern __inline__ void pmd_free(pmd_t *pmd)
+{
+ free_page((unsigned long)pmd);
+}
+
+#define __pmd_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
#endif
#define check_pgt_cache() do { } while (0)
diff --git a/include/asm-um/pgtable-3level.h b/include/asm-um/pgtable-3level.h
index 32cd6236f245..786c25727289 100644
--- a/include/asm-um/pgtable-3level.h
+++ b/include/asm-um/pgtable-3level.h
@@ -69,14 +69,11 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
return pmd;
}
-static inline void pmd_free(pmd_t *pmd){
- free_page((unsigned long) pmd);
+extern inline void pud_clear (pud_t *pud)
+{
+ set_pud(pud, __pud(0));
}
-#define __pmd_free_tlb(tlb,x) do { } while (0)
-
-static inline void pud_clear (pud_t * pud) { }
-
#define pud_page(pud) \
((struct page *) __va(pud_val(pud) & PAGE_MASK))
--
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