linux/fs/proc
KAMEZAWA Hiroyuki 9e7814404b hold task->mempolicy while numa_maps scans.
/proc/<pid>/numa_maps scans vma and show mempolicy under
  mmap_sem. It sometimes accesses task->mempolicy which can
  be freed without mmap_sem and numa_maps can show some
  garbage while scanning.

This patch tries to take reference count of task->mempolicy at reading
numa_maps before calling get_vma_policy(). By this, task->mempolicy
will not be freed until numa_maps reaches its end.

V2->v3
  -  updated comments to be more verbose.
  -  removed task_lock() in numa_maps code.
V1->V2
  -  access task->mempolicy only once and remember it.  Becase kernel/exit.c
     can overwrite it.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-19 14:32:10 -07:00
..
array.c c/r: procfs: add arg_start/end, env_start/end and exit_code members to /proc/$pid/stat 2012-05-31 17:49:32 -07:00
base.c procfs: don't need a PATH_MAX allocation to hold a string representation of an int 2012-10-12 20:15:10 -04:00
cmdline.c
consoles.c
cpuinfo.c
devices.c
fd.c don't leak O_CLOEXEC into ->f_flags 2012-09-26 21:10:01 -04:00
fd.h procfs: Move /proc/pid/fd[info] handling code to fd.[ch] 2012-09-26 21:10:01 -04:00
generic.c proc: use kzalloc instead of kmalloc and memset 2012-10-06 03:05:18 +09:00
inode.c proc: no need to initialize proc_inode->fd in proc_get_inode() 2012-10-06 03:05:18 +09:00
internal.h hold task->mempolicy while numa_maps scans. 2012-10-19 14:32:10 -07:00
interrupts.c
Kconfig
kcore.c
kmsg.c
loadavg.c
Makefile procfs: Move /proc/pid/fd[info] handling code to fd.[ch] 2012-09-26 21:10:01 -04:00
meminfo.c
mmu.c
namespaces.c stop passing nameidata to ->lookup() 2012-07-14 16:34:32 +04:00
nommu.c
page.c kpageflags: fix wrong KPF_THP on non-huge compound pages 2012-10-09 16:23:00 +09:00
proc_devtree.c of: Improve prom_update_property() function 2012-07-11 15:26:51 +10:00
proc_net.c stop passing nameidata to ->lookup() 2012-07-14 16:34:32 +04:00
proc_sysctl.c rbtree: fix incorrect rbtree node insertion in fs/proc/proc_sysctl.c 2012-10-09 16:22:32 +09:00
proc_tty.c
root.c fs/proc/root.c: use NULL instead of 0 for pointer 2012-10-06 03:05:19 +09:00
softirqs.c
stat.c
task_mmu.c hold task->mempolicy while numa_maps scans. 2012-10-19 14:32:10 -07:00
task_nommu.c
uptime.c
version.c
vmcore.c