uprobes: __replace_page() needs munlock_vma_page()

Like do_wp_page(), __replace_page() should do munlock_vma_page()
for the case when the old page still has other !VM_LOCKED
mappings. Unfortunately this needs mm/internal.h.

Also, move put_page() outside of ptl lock. This doesn't really
matter but looks a bit better.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com>
Cc: Anton Arapov <anton@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20120729182249.GA20372@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Oleg Nesterov 2012-07-29 20:22:49 +02:00 committed by Ingo Molnar
parent 57683f72b8
commit 194f8dcbe9

View File

@ -32,6 +32,7 @@
#include <linux/swap.h> /* try_to_free_swap */
#include <linux/ptrace.h> /* user_enable_single_step */
#include <linux/kdebug.h> /* notifier mechanism */
#include "../../mm/internal.h" /* munlock_vma_page */
#include <linux/uprobes.h>
@ -141,7 +142,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
pte_t *ptep;
int err;
/* freeze PageSwapCache() for try_to_free_swap() below */
/* For try_to_free_swap() and munlock_vma_page() below */
lock_page(page);
err = -EAGAIN;
@ -164,9 +165,12 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
page_remove_rmap(page);
if (!page_mapped(page))
try_to_free_swap(page);
put_page(page);
pte_unmap_unlock(ptep, ptl);
if (vma->vm_flags & VM_LOCKED)
munlock_vma_page(page);
put_page(page);
err = 0;
unlock:
unlock_page(page);