linux/arch
Benjamin Herrenschmidt 6c16a74d42 powerpc/mm: Fix potential access to freed pages when using hugetlbfs
When using 64k page sizes, our PTE pages are split in two halves,
the second half containing the "extension" used to keep track of
individual 4k pages when not using HW 64k pages.

However, our page tables used for hugetlb have a slightly different
format and don't carry that "second half".

Our code that batched PTEs to be invalidated unconditionally reads
the "second half" (to put it into the batch), which means that when
called to invalidate hugetlb PTEs, it will access unrelated memory.

It breaks when CONFIG_DEBUG_PAGEALLOC is enabled.

This fixes it by only accessing the second half when the _PAGE_COMBO
bit is set in the first half, which indicates that we are dealing with
a "combo" page which represents 16x4k subpages. Anything else shouldn't
have this bit set and thus not require loading from the second half.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-06-26 16:55:36 +10:00
..
alpha Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
arm Merge git://git.infradead.org/mtd-2.6 2009-06-22 16:56:22 -07:00
avr32 Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
blackfin Blackfin: fix dma-mapping build errors 2009-06-22 22:31:00 -04:00
cris Merge branch 'for-linus' of git://www.jni.nu/cris 2009-06-23 10:47:01 -07:00
frv Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
h8300 h8/300: fix incorrect "select" directives in arch/h8300/Kconfig.cpu. 2009-06-23 12:50:05 -07:00
ia64 Merge branches 'acerhdf', 'acpi-pci-bind', 'bjorn-pci-root', 'bugzilla-12904', 'bugzilla-13121', 'bugzilla-13396', 'bugzilla-13533', 'bugzilla-13612', 'c3_lock', 'hid-cleanups', 'misc-2.6.31', 'pdc-leak-fix', 'pnpacpi', 'power_nocheck', 'thinkpad_acpi', 'video' and 'wmi' into release 2009-06-24 01:19:50 -04:00
m32r Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
m68k Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
m68knommu ptrace: remove PT_DTRACE from m68k, m68knommu 2009-06-18 13:03:48 -07:00
microblaze Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
mips MIPS: Cavium: Add CPU hotplugging code. 2009-06-24 18:34:40 +01:00
mn10300 MN10300: Fix the vmlinux ldscript 2009-06-22 13:34:50 -07:00
parisc Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
powerpc powerpc/mm: Fix potential access to freed pages when using hugetlbfs 2009-06-26 16:55:36 +10:00
s390 [S390] Update default configuration. 2009-06-22 12:08:25 +02:00
sh sh: Fix up HAVE_PERF_COUNTERS typo. 2009-06-24 01:41:05 +09:00
sparc Move FAULT_FLAG_xyz into handle_mm_fault() callers 2009-06-21 13:08:22 -07:00
um UML: Fix some apparent bitrot 2009-06-25 11:22:13 -07:00
x86 Revert "PCI: use ACPI _CRS data by default" 2009-06-24 16:23:03 -07:00
xtensa xtensa: enable m41t80 driver in s6105_defconfig 2009-06-22 02:38:11 -07:00
.gitignore
Kconfig gcov: add gcov profiling infrastructure 2009-06-18 13:03:57 -07:00