linux/include
Toshi Kani 87ebcc534d base/memory, hotplug: fix a kernel oops in show_valid_zones()
commit a96dfddbcc upstream.

Reading a sysfs "memoryN/valid_zones" file leads to the following oops
when the first page of a range is not backed by struct page.
show_valid_zones() assumes that 'start_pfn' is always valid for
page_zone().

 BUG: unable to handle kernel paging request at ffffea017a000000
 IP: show_valid_zones+0x6f/0x160

This issue may happen on x86-64 systems with 64GiB or more memory since
their memory block size is bumped up to 2GiB.  [1] An example of such
systems is desribed below.  0x3240000000 is only aligned by 1GiB and
this memory block starts from 0x3200000000, which is not backed by
struct page.

 BIOS-e820: [mem 0x0000003240000000-0x000000603fffffff] usable

Since test_pages_in_a_zone() already checks holes, fix this issue by
extending this function to return 'valid_start' and 'valid_end' for a
given range.  show_valid_zones() then proceeds with the valid range.

[1] 'Commit bdee237c03 ("x86: mm: Use 2GB memory block size on
    large-memory x86-64 systems")'

Link: http://lkml.kernel.org/r/20170127222149.30893-3-toshi.kani@hpe.com
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Zhang Zhen <zhenzhang.zhang@huawei.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>	[4.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-09 08:02:47 +01:00
..
acpi Merge branch 'acpi-pci' 2015-11-07 01:30:10 +01:00
asm-generic asm-generic: make copy_from_user() zero the destination properly 2016-09-24 10:07:45 +02:00
clocksource
crypto crypto: ghash-generic - move common definitions to a new header file 2016-10-22 12:26:56 +02:00
drm drm/prime: Pass the right module owner through to dma_buf_export() 2016-10-31 04:13:57 -06:00
dt-bindings ARM: DT updates for v4.4 2015-11-10 15:06:26 -08:00
keys KEYS: Merge the type-specific data with the payload data 2015-10-21 15:18:36 +01:00
kvm KVM: arm/arm64: arch_timer: Preserve physical dist. active state on LR.active 2015-11-24 18:07:40 +01:00
linux base/memory, hotplug: fix a kernel oops in show_valid_zones() 2017-02-09 08:02:47 +01:00
math-emu
media videobuf2-core: Check user space planes array in dqbuf 2016-05-04 14:48:50 -07:00
memory
misc
net cfg80211/mac80211: fix BSS leaks when abandoning assoc attempts 2017-01-09 08:07:42 +01:00
pcmcia
ras
rdma IB/cma: Fix a race condition in iboe_addr_get_sgid() 2017-01-09 08:07:51 +01:00
rxrpc
scsi scsi: Add intermediate STARGET_REMOVE state to scsi_target_state 2016-06-01 12:15:54 -07:00
soc ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
sound ALSA: rawmidi: Make snd_rawmidi_transmit() race-free 2016-02-17 12:30:58 -08:00
target target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLE 2016-10-28 03:01:36 -04:00
trace SUNRPC: Don't allocate a full sockaddr_storage for tracing 2016-08-20 18:09:26 +02:00
uapi can: raw: raw_setsockopt: limit number of can_filter that can be set 2016-12-15 08:49:22 -08:00
video drm/imx: Match imx-ipuv3-crtc components using device node in platform data 2016-06-07 18:14:37 -07:00
xen xen: Fix page <-> pfn conversion on 32 bit systems 2016-05-11 11:21:14 +02:00
Kbuild