diff options
author | Haggai Eran <haggaie@mellanox.com> | 2012-10-08 16:33:35 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-10-09 16:22:58 +0900 |
commit | 6bdb913f0a70a4dfb7f066fb15e2d6f960701d00 (patch) | |
tree | 9a61960b27bf801794104b8bb8fccee1813f1b4b /kernel | |
parent | 2ec74c3ef2d8c58d71e0e00336fb6b891192155a (diff) |
mm: wrap calls to set_pte_at_notify with invalidate_range_start and invalidate_range_end
In order to allow sleeping during invalidate_page mmu notifier calls, we
need to avoid calling when holding the PT lock. In addition to its direct
calls, invalidate_page can also be called as a substitute for a change_pte
call, in case the notifier client hasn't implemented change_pte.
This patch drops the invalidate_page call from change_pte, and instead
wraps all calls to change_pte with invalidate_range_start and
invalidate_range_end calls.
Note that change_pte still cannot sleep after this patch, and that clients
implementing change_pte should not take action on it in case the number of
outstanding invalidate_range_start calls is larger than one, otherwise
they might miss a later invalidation.
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Cc: Andrea Arcangeli <andrea@qumranet.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Haggai Eran <haggaie@mellanox.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Cc: Liran Liss <liranl@mellanox.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Avi Kivity <avi@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/events/uprobes.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 1d9c0a98596..98256bc71ee 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -141,10 +141,14 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, spinlock_t *ptl; pte_t *ptep; int err; + /* For mmu_notifiers */ + const unsigned long mmun_start = addr; + const unsigned long mmun_end = addr + PAGE_SIZE; /* For try_to_free_swap() and munlock_vma_page() below */ lock_page(page); + mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); err = -EAGAIN; ptep = page_check_address(page, mm, addr, &ptl, 0); if (!ptep) @@ -173,6 +177,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, err = 0; unlock: + mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); unlock_page(page); return err; } |