linux/arch/mips
David Daney 88d02a2ba6 MIPS: Fix page table corruption on THP permission changes.
When the core THP code is modifying the permissions of a huge page it
calls pmd_modify(), which unfortunately was clearing the _PAGE_HUGE bit
of the page table entry.  The result can be kernel messages like:

mm/memory.c:397: bad pmd 000000040080004d.
mm/memory.c:397: bad pmd 00000003ff00004d.
mm/memory.c:397: bad pmd 000000040100004d.

or:

------------[ cut here ]------------
WARNING: at mm/mmap.c:3200 exit_mmap+0x150/0x158()
Modules linked in: ipv6 at24 octeon3_ethernet octeon_srio_nexus m25p80
CPU: 12 PID: 1295 Comm: pmderr Not tainted 3.10.87-rt80-Cavium-Octeon #4
Stack : 0000000040808000 0000000014009ce1 0000000000400004 ffffffff81076ba0
          0000000000000000 0000000000000000 ffffffff85110000 0000000000000119
          0000000000000004 0000000000000000 0000000000000119 43617669756d2d4f
          0000000000000000 ffffffff850fda40 ffffffff85110000 0000000000000000
          0000000000000000 0000000000000009 ffffffff809207a0 0000000000000c80
          ffffffff80f1bf20 0000000000000001 000000ffeca36828 0000000000000001
          0000000000000000 0000000000000001 000000ffeca7e700 ffffffff80886924
          80000003fd7a0000 80000003fd7a39b0 80000003fdea8000 ffffffff80885780
          80000003fdea8000 ffffffff80f12218 000000000000000c 000000000000050f
          0000000000000000 ffffffff80865c4c 0000000000000000 0000000000000000
          ...
Call Trace:
[<ffffffff80865c4c>] show_stack+0x6c/0xf8
[<ffffffff80885780>] warn_slowpath_common+0x78/0xa8
[<ffffffff809207a0>] exit_mmap+0x150/0x158
[<ffffffff80882d44>] mmput+0x5c/0x110
[<ffffffff8088b450>] do_exit+0x230/0xa68
[<ffffffff8088be34>] do_group_exit+0x54/0x1d0
[<ffffffff8088bfc0>] __wake_up_parent+0x0/0x18

---[ end trace c7b38293191c57dc ]---
BUG: Bad rss-counter state mm:80000003fa168000 idx:1 val:1536

Fix by not clearing _PAGE_HUGE bit.

Signed-off-by: David Daney <david.daney@cavium.com>
Tested-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13687/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-07-06 15:09:03 +02:00
..
alchemy Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-05-19 10:02:26 -07:00
ar7
ath25
ath79 TTY and Serial driver update for 4.7-rc1 2016-05-20 20:57:27 -07:00
bcm47xx MIPS: BCM47xx: Move SPROM driver to drivers/firmware/ 2016-05-13 14:01:43 +02:00
bcm63xx
bmips MIPS: BMIPS: Add support for BCM63268 2016-05-13 14:02:09 +02:00
boot MIPS: devicetree: fix cpu interrupt controller node-names 2016-05-28 12:35:12 +02:00
cavium-octeon MIPS: Add missing FROZEN hotplug notifier transitions 2016-05-28 12:35:12 +02:00
cobalt
configs arch/defconfig: remove CONFIG_RESOURCE_COUNTERS 2016-05-23 17:04:14 -07:00
dec MIPS: DEC: Export `ioasic_ssr_lock' to modules 2016-05-17 11:03:54 +02:00
emma
fw MIPS: Fix misspellings in comments. 2016-04-03 12:32:09 +02:00
include MIPS: Fix page table corruption on THP permission changes. 2016-07-06 15:09:03 +02:00
jazz
jz4740 MTD updates for v4.7: 2016-05-24 11:00:20 -07:00
kernel Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-05-28 16:41:39 -07:00
kvm MIPS: KVM: Fix CACHE triggered exception emulation 2016-06-14 10:59:45 +02:00
lantiq MIPS: Change my email address 2016-05-13 14:02:18 +02:00
lasat MIPS: Lasat: A couple off by one bugs in picvue_proc.c 2016-05-28 12:35:06 +02:00
lib MIPS: lib: Mark intrinsics notrace 2016-05-28 12:35:11 +02:00
loongson32 MIPS: Loongson1B: Some updates/fixes for LS1B 2016-05-13 14:02:05 +02:00
loongson64 MIPS: Loongson64: Fix typo 2016-05-28 12:35:07 +02:00
math-emu MIPS: math-emu: Fix typo 2016-05-28 12:35:09 +02:00
mm Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-05-28 16:41:39 -07:00
mti-malta MIPS: malta-time: Take seconds into account 2016-05-13 15:30:25 +02:00
mti-sead3 MIPS: Introduce plat_get_fdt a platform API to retrieve the FDT 2016-05-13 14:02:03 +02:00
net
netlogic MIPS: Define & use CP0_EBase bit definitions 2016-05-13 15:30:25 +02:00
oprofile MIPS: oprofile: Fix typo 2016-05-28 12:35:09 +02:00
paravirt
pci MIPS: IP27: Fix typo 2016-05-28 12:35:07 +02:00
pic32 Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-05-19 10:02:26 -07:00
pistachio MIPS: Pistachio: Enable KASLR 2016-05-28 12:35:11 +02:00
pmcs-msp71xx MIPS: MSP71xx: Use __flush_cache_all instead of flush_cache_all. 2016-05-13 14:01:38 +02:00
pnx833x MIPS: make PCI_DMA_BUS_IS_PHYS=1 constant 2016-05-13 14:02:17 +02:00
power
ralink MIPS: ralink: add MT7628 EPHY LEDs pinmux support 2016-05-28 12:35:05 +02:00
rb532
sgi-ip22
sgi-ip27 MIPS: Spelling fix lets -> let's 2016-05-28 12:35:09 +02:00
sgi-ip32
sibyte MIPS: Sibyte: Fix Kconfig dependencies of SIBYTE_BUS_WATCHER 2016-05-09 12:00:03 +02:00
sni MIPS: Spelling fix lets -> let's 2016-05-28 12:35:09 +02:00
txx9
vdso MIPS: Build microMIPS VDSO for microMIPS kernels 2016-05-28 12:35:12 +02:00
vr41xx MIPS: VR41xx: Fix typo 2016-05-28 12:35:09 +02:00
xilfpga
Kbuild
Kbuild.platforms
Kconfig Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-05-28 16:41:39 -07:00
Kconfig.debug
Makefile MIPS: Fix VZ probe gas errors with binutils <2.24 2016-05-17 11:06:04 +02:00