raspi/linux
1
0
Fork 1
mirror of https://github.com/raspberrypi/linux.git synced 2025-12-06 18:09:56 +00:00
Code Issues Projects Releases Wiki Activity

ARC: fix page address calculation if PAGE_OFFSET != LINUX_LINK_BASE

Browse Source 
commit 06f34e1c28 upstream.

We used to calculate page address differently in 2 cases:

1. In virt_to_page(x) we do
 --->8---
 mem_map + (x - CONFIG_LINUX_LINK_BASE) >> PAGE_SHIFT
 --->8---

2. In in pte_page(x) we do
 --->8---
 mem_map + (pte_val(x) - PAGE_OFFSET) >> PAGE_SHIFT
 --->8---

That leads to problems in case PAGE_OFFSET != CONFIG_LINUX_LINK_BASE -
different pages will be selected depending on where and how we calculate
page address.

In particular in the STAR 9000853582 when gdb attempted to read memory
of another process it got improper page in get_user_pages() because this
is exactly one of the places where we search for a page by pte_page().

The fix is trivial - we need to calculate page address similarly in both
cases.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Alexey Brodkin
2015-02-12 21:10:11 +03:00
committed by Greg Kroah-Hartman
parent 8f9b87b3dc
commit b3b345af59
1 changed files with 2 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
arch/arc/include/asm/pgtable.h
View File

@@ -259,7 +259,8 @@ static inline void pmd_set(pmd_t *pmdp, pte_t *ptep)
#define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0) #define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0)
#define pte_page(x) (mem_map + \ #define pte_page(x) (mem_map + \
(unsigned long)(((pte_val(x) - PAGE_OFFSET) >> PAGE_SHIFT))) (unsigned long)(((pte_val(x) - CONFIG_LINUX_LINK_BASE) >> \
PAGE_SHIFT)))
#define mk_pte(page, pgprot) \ #define mk_pte(page, pgprot) \
({ \ ({ \