Subject: + mm-mempolicy-fix-mbind_range-vma_adjust-interaction.patch added to -mm tree
To: oleg@xxxxxxxxxx,andi@xxxxxxxxxxxxxx,kosaki.motohiro@xxxxxxxxxxxxxx,mgorman@xxxxxxx,riel@xxxxxxxxxx,stable@xxxxxxxxxxxxxxx,steven.t.hampson@xxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Tue, 09 Jul 2013 14:56:50 -0700
The patch titled
Subject: mm: mempolicy: fix mbind_range() && vma_adjust() interaction
has been added to the -mm tree. Its filename is
mm-mempolicy-fix-mbind_range-vma_adjust-interaction.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-mempolicy-fix-mbind_range-vma_adjust-interaction.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-mempolicy-fix-mbind_range-vma_adjust-interaction.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Oleg Nesterov <oleg@xxxxxxxxxx>
Subject: mm: mempolicy: fix mbind_range() && vma_adjust() interaction
vma_adjust() does vma_set_policy(vma, vma_policy(next)) and this
is doubly wrong:
1. This leaks vma->vm_policy if it is not NULL and not equal to
next->vm_policy.
This can happen if vma_merge() expands "area", not prev (case 8).
2. This sets the wrong policy if vma_merge() joins prev and area,
area is the vma the caller needs to update and it still has the
old policy.
Revert 1444f92c "mm: merging memory blocks resets mempolicy" which
introduced these problems.
Change mbind_range() to recheck mpol_equal() after vma_merge() to
fix the problem 1444f92c tried to address.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Steven T Hampson <steven.t.hampson@xxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxx>
Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
Cc: Rik van Riel <riel@xxxxxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mempolicy.c | 6 +++++-
mm/mmap.c | 2 +-
2 files changed, 6 insertions(+), 2 deletions(-)
diff -puN mm/mempolicy.c~mm-mempolicy-fix-mbind_range-vma_adjust-interaction mm/mempolicy.c
--- a/mm/mempolicy.c~mm-mempolicy-fix-mbind_range-vma_adjust-interaction
+++ a/mm/mempolicy.c
@@ -732,7 +732,10 @@ static int mbind_range(struct mm_struct
if (prev) {
vma = prev;
next = vma->vm_next;
- continue;
+ if (mpol_equal(vma_policy(vma), new_pol))
+ continue;
+ /* vma_merge() joined vma && vma->next, case 8 */
+ goto replace;
}
if (vma->vm_start != vmstart) {
err = split_vma(vma->vm_mm, vma, vmstart, 1);
@@ -744,6 +747,7 @@ static int mbind_range(struct mm_struct
if (err)
goto out;
}
+ replace:
err = vma_replace_policy(vma, new_pol);
if (err)
goto out;
diff -puN mm/mmap.c~mm-mempolicy-fix-mbind_range-vma_adjust-interaction mm/mmap.c
--- a/mm/mmap.c~mm-mempolicy-fix-mbind_range-vma_adjust-interaction
+++ a/mm/mmap.c
@@ -865,7 +865,7 @@ again: remove_next = 1 + (end > next->
if (next->anon_vma)
anon_vma_merge(vma, next);
mm->map_count--;
- vma_set_policy(vma, vma_policy(next));
+ mpol_put(vma_policy(next));
kmem_cache_free(vm_area_cachep, next);
/*
* In mprotect's case 6 (see comments on vma_merge),
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
origin.patch
vfree-dont-schedule-free_work-if-llist_add-returns-false.patch
ptrace-x86-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-arm-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-sh-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch
ptrace-revert-prepare-to-fix-racy-accesses-on-task-breakpoints.patch
ptrace-x86-simplify-the-disable-logic-in-ptrace_write_dr7.patch
ptrace-x86-dont-delay-disable-till-second-pass-in-ptrace_write_dr7.patch
ptrace-x86-introduce-ptrace_register_breakpoint.patch
ptrace-x86-ptrace_write_dr7-should-create-bp-if-disabled.patch
ptrace-x86-cleanup-ptrace_set_debugreg.patch
ptrace-ptrace_detach-should-do-flush_ptrace_hw_breakpointchild.patch
ptrace-x86-flush_ptrace_hw_breakpoint-shoule-clear-the-virtual-debug-registers.patch
linux-next.patch
mm-mempolicy-fix-mbind_range-vma_adjust-interaction.patch
include-linux-schedh-dont-use-task-pid-tgid-in-same_thread_group-has_group_leader_pid.patch
lockdep-introduce-lock_acquire_exclusive-shared-helper-macros.patch
lglock-update-lockdep-annotations-to-report-recursive-local-locks.patch
fput-task_work_add-can-fail-if-the-caller-has-passed-exit_task_work-fix.patch
fput-turn-list_head-delayed_fput_list-into-llist_head.patch
llist-fix-simplify-llist_add-and-llist_add_batch.patch
llist-llist_add-can-use-llist_add_batch.patch
autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch
autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch
signals-eventpoll-set-saved_sigmask-at-the-start.patch
move-exit_task_namespaces-outside-of-exit_notify-fix.patch
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