Commit 7ef93905 authored by Jeff Dike's avatar Jeff Dike Committed by Linus Torvalds
Browse files

[PATCH] uml: fix x86_64 page leak 



We were leaking pmd pages when 3_LEVEL_PGTABLES was enabled.  This fixes that.

Signed-off-by: default avatarJeff Dike <jdike@addtoit.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent f9dfefe4

arch/um/kernel/skas/include/mmu-skas.h

+4 −0
Original line number Diff line number Diff line
@@ -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);

arch/um/kernel/skas/mmu.c

+8 −1
Original line number Diff line number Diff line
@@ -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

	}

}

include/asm-um/pgalloc.h

+7 −5
Original line number Diff line number Diff line
@@ -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)

include/asm-um/pgtable-3level.h

+3 −6
Original line number Diff line number Diff line
@@ -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))