linux/fs/proc
Naoya Horiguchi d4c54919ed mm: add !pte_present() check on existing hugetlb_entry callbacks
The age table walker doesn't check non-present hugetlb entry in common
path, so hugetlb_entry() callbacks must check it.  The reason for this
behavior is that some callers want to handle it in its own way.

[ I think that reason is bogus, btw - it should just do what the regular
  code does, which is to call the "pte_hole()" function for such hugetlb
  entries  - Linus]

However, some callers don't check it now, which causes unpredictable
result, for example when we have a race between migrating hugepage and
reading /proc/pid/numa_maps.  This patch fixes it by adding !pte_present
checks on buggy callbacks.

This bug exists for years and got visible by introducing hugepage
migration.

ChangeLog v2:
- fix if condition (check !pte_present() instead of pte_present())

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: <stable@vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Backported to 3.15.  Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org> ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 13:21:16 -07:00
..
array.c wait: swap EXIT_ZOMBIE and EXIT_DEAD to hide EXIT_TRACE from user-space 2014-04-07 16:36:06 -07:00
base.c Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
cmdline.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
consoles.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
cpuinfo.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
devices.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
fd.c proc: show mnt_id in /proc/pid/fdinfo 2014-04-07 16:36:04 -07:00
fd.h proc: Move proc_fd() to fs/proc/fd.h 2013-05-01 17:29:39 -04:00
generic.c proc: set attributes of pde using accessor functions 2014-01-23 16:37:01 -08:00
inode.c fs/proc/inode.c: use RCU_INIT_POINTER(x, NULL) 2014-04-07 16:36:04 -07:00
internal.h of: remove /proc/device-tree 2014-03-11 20:48:32 +00:00
interrupts.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
Kconfig kcore: add Kconfig help text 2013-11-13 12:09:33 +09:00
kcore.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
kmsg.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
loadavg.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
Makefile of: remove /proc/device-tree 2014-03-11 20:48:32 +00:00
meminfo.c fs/proc/meminfo: meminfo_proc_show(): fix typo in comment 2014-04-07 16:36:04 -07:00
namespaces.c new helper: readlink_copy() 2014-04-01 23:19:15 -04:00
nommu.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
page.c mm: close PageTail race 2014-03-04 07:55:47 -08:00
proc_net.c [readdir] convert procfs 2013-06-29 12:56:32 +04:00
proc_sysctl.c Don't pass inode to ->d_hash() and ->d_compare() 2013-06-29 12:57:36 +04:00
proc_tty.c proc: use seq_puts()/seq_putc() where possible 2011-01-13 08:03:16 -08:00
root.c Major changes for 3.14 include support for the newly added ZERO_RANGE 2014-04-04 15:39:39 -07:00
self.c new helper: readlink_copy() 2014-04-01 23:19:15 -04:00
softirqs.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
stat.c cputime: Default implementation of nsecs -> cputime conversion 2014-03-13 15:56:43 +01:00
task_mmu.c mm: add !pte_present() check on existing hugetlb_entry callbacks 2014-06-06 13:21:16 -07:00
task_nommu.c seq_file: remove "%n" usage from seq_file users 2013-11-15 09:32:20 +09:00
uptime.c cputime: Default implementation of nsecs -> cputime conversion 2014-03-13 15:56:43 +01:00
version.c fs/proc: don't use module_init for non-modular core code 2014-01-23 16:37:02 -08:00
vmcore.c vmcore: continue vmcore initialization if PT_NOTE is found empty 2014-04-07 16:36:06 -07:00