From 8ca3eb08097f6839b2206e2242db4179aee3cfb3 Mon Sep 17 00:00:00 2001
From: "Luck, Tony" <tony.luck@intel.com>
Date: Tue, 24 Aug 2010 11:44:18 -0700
Subject: guard page for stacks that grow upwards
pa-risc and ia64 have stacks that grow upwards. Check that
they do not run into other mappings. By making VM_GROWSUP
0x0 on architectures that do not ever use it, we can avoid
some unpleasant #ifdefs in check_stack_guard_page().
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/mm.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
(limited to 'include/linux/mm.h')
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 709f6728fc9..831c693416b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -78,7 +78,11 @@ extern unsigned int kobjsize(const void *objp);
#define VM_MAYSHARE 0x00000080
#define VM_GROWSDOWN 0x00000100 /* general info on the segment */
+#if defined(CONFIG_STACK_GROWSUP) || defined(CONFIG_IA64)
#define VM_GROWSUP 0x00000200
+#else
+#define VM_GROWSUP 0x00000000
+#endif
#define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */
#define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */
@@ -1330,8 +1334,10 @@ unsigned long ra_submit(struct file_ra_state *ra,
/* Do stack extension */
extern int expand_stack(struct vm_area_struct *vma, unsigned long address);
-#ifdef CONFIG_IA64
+#if VM_GROWSUP
extern int expand_upwards(struct vm_area_struct *vma, unsigned long address);
+#else
+ #define expand_upwards(vma, address) do { } while (0)
#endif
extern int expand_stack_downwards(struct vm_area_struct *vma,
unsigned long address);
--
cgit v1.2.3-70-g09d2
From bad849b3dc0fae1297c8d47f846f8d202a6145ed Mon Sep 17 00:00:00 2001
From: David Howells <dhowells@redhat.com>
Date: Thu, 26 Aug 2010 16:00:34 +0100
Subject: NOMMU: Stub out vm_get_page_prot() if there's no MMU
Stub out vm_get_page_prot() if there's no MMU.
This was added by commit 804af2cf6e7a ("[AGPGART] remove private page
protection map") and is used in commit c07fbfd17e61 ("fbmem: VM_IO set,
but not propagated") in the fbmem video driver, but the function doesn't
exist on NOMMU, resulting in an undefined symbol at link time.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/mm.h | 8 ++++++++
1 file changed, 8 insertions(+)
(limited to 'include/linux/mm.h')
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 831c693416b..e6b1210772c 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1363,7 +1363,15 @@ static inline unsigned long vma_pages(struct vm_area_struct *vma)
return (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
}
+#ifdef CONFIG_MMU
pgprot_t vm_get_page_prot(unsigned long vm_flags);
+#else
+static inline pgprot_t vm_get_page_prot(unsigned long vm_flags)
+{
+ return __pgprot(0);
+}
+#endif
+
struct vm_area_struct *find_extend_vma(struct mm_struct *, unsigned long addr);
int remap_pfn_range(struct vm_area_struct *, unsigned long addr,
unsigned long pfn, unsigned long size, pgprot_t);
--
cgit v1.2.3-70-g09d2
From 39aa3cb3e8250db9188a6f1e3fb62ffa1a717678 Mon Sep 17 00:00:00 2001
From: Stefan Bader <stefan.bader@canonical.com>
Date: Tue, 31 Aug 2010 15:52:27 +0200
Subject: mm: Move vma_stack_continue into mm.h
So it can be used by all that need to check for that.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
fs/proc/task_mmu.c | 3 ++-
include/linux/mm.h | 6 ++++++
mm/mlock.c | 6 ------
3 files changed, 8 insertions(+), 7 deletions(-)
(limited to 'include/linux/mm.h')
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 439fc1f1c1c..271afc48b9a 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -224,7 +224,8 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
/* We don't show the stack guard page in /proc/maps */
start = vma->vm_start;
if (vma->vm_flags & VM_GROWSDOWN)
- start += PAGE_SIZE;
+ if (!vma_stack_continue(vma->vm_prev, vma->vm_start))
+ start += PAGE_SIZE;
seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
start,
diff --git a/include/linux/mm.h b/include/linux/mm.h
index e6b1210772c..74949fbef8c 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -864,6 +864,12 @@ int set_page_dirty(struct page *page);
int set_page_dirty_lock(struct page *page);
int clear_page_dirty_for_io(struct page *page);
+/* Is the vma a continuation of the stack vma above it? */
+static inline int vma_stack_continue(struct vm_area_struct *vma, unsigned long addr)
+{
+ return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
+}
+
extern unsigned long move_page_tables(struct vm_area_struct *vma,
unsigned long old_addr, struct vm_area_struct *new_vma,
unsigned long new_addr, unsigned long len);
diff --git a/mm/mlock.c b/mm/mlock.c
index cbae7c5b956..b70919ce4f7 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -135,12 +135,6 @@ void munlock_vma_page(struct page *page)
}
}
-/* Is the vma a continuation of the stack vma above it? */
-static inline int vma_stack_continue(struct vm_area_struct *vma, unsigned long addr)
-{
- return vma && (vma->vm_end == addr) && (vma->vm_flags & VM_GROWSDOWN);
-}
-
static inline int stack_guard_page(struct vm_area_struct *vma, unsigned long addr)
{
return (vma->vm_flags & VM_GROWSDOWN) &&
--
cgit v1.2.3-70-g09d2