linux/fs/proc
Peter Feiner 68b5a65248 mm: softdirty: respect VM_SOFTDIRTY in PTE holes
After a VMA is created with the VM_SOFTDIRTY flag set, /proc/pid/pagemap
should report that the VMA's virtual pages are soft-dirty until
VM_SOFTDIRTY is cleared (i.e., by the next write of "4" to
/proc/pid/clear_refs).  However, pagemap ignores the VM_SOFTDIRTY flag
for virtual addresses that fall in PTE holes (i.e., virtual addresses
that don't have a PMD, PUD, or PGD allocated yet).

To observe this bug, use mmap to create a VMA large enough such that
there's a good chance that the VMA will occupy an unused PMD, then test
the soft-dirty bit on its pages.  In practice, I found that a VMA that
covered a PMD's worth of address space was big enough.

This patch adds the necessary VMA lookup to the PTE hole callback in
/proc/pid/pagemap's page walk and sets soft-dirty according to the VMAs'
VM_SOFTDIRTY flag.

Signed-off-by: Peter Feiner <pfeiner@google.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Hugh Dickins <hughd@google.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:22 -07:00
..
array.c Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2014-08-06 08:06:39 -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 mm: export NR_SHMEM via sysinfo(2) / si_meminfo() interfaces 2014-08-06 18:01:19 -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 /proc/stat: convert to single_open_size() 2014-07-03 09:21:54 -07:00
task_mmu.c mm: softdirty: respect VM_SOFTDIRTY in PTE holes 2014-08-06 18:01:22 -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 fs/proc/vmcore.c: remove NULL assignment to static 2014-06-06 16:08:12 -07:00