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authorJason Gunthorpe <jgg@mellanox.com>2018-01-29 23:26:40 +0300
committerJason Gunthorpe <jgg@mellanox.com>2018-01-30 19:30:00 +0300
commite7996a9a77fc669387da43ff4823b91cc4872bd0 (patch)
tree617f0a128e222539d67e8cccc359f1bc4b984900 /fs/userfaultfd.c
parentb5fa635aab8f0d39a824c01991266a6d06f007fb (diff)
parentd8a5b80568a9cb66810e75b182018e9edb68e8ff (diff)
downloadlinux-e7996a9a77fc669387da43ff4823b91cc4872bd0.tar.xz
Merge tag v4.15 of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
To resolve conflicts in: drivers/infiniband/hw/mlx5/main.c drivers/infiniband/hw/mlx5/qp.c From patches merged into the -rc cycle. The conflict resolution matches what linux-next has been carrying. Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Diffstat (limited to 'fs/userfaultfd.c')
-rw-r--r--fs/userfaultfd.c20
1 files changed, 18 insertions, 2 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index ac9a4e65ca49..41a75f9f23fd 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -570,11 +570,14 @@ out:
static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
struct userfaultfd_wait_queue *ewq)
{
+ struct userfaultfd_ctx *release_new_ctx;
+
if (WARN_ON_ONCE(current->flags & PF_EXITING))
goto out;
ewq->ctx = ctx;
init_waitqueue_entry(&ewq->wq, current);
+ release_new_ctx = NULL;
spin_lock(&ctx->event_wqh.lock);
/*
@@ -601,8 +604,7 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
new = (struct userfaultfd_ctx *)
(unsigned long)
ewq->msg.arg.reserved.reserved1;
-
- userfaultfd_ctx_put(new);
+ release_new_ctx = new;
}
break;
}
@@ -617,6 +619,20 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx,
__set_current_state(TASK_RUNNING);
spin_unlock(&ctx->event_wqh.lock);
+ if (release_new_ctx) {
+ struct vm_area_struct *vma;
+ struct mm_struct *mm = release_new_ctx->mm;
+
+ /* the various vma->vm_userfaultfd_ctx still points to it */
+ down_write(&mm->mmap_sem);
+ for (vma = mm->mmap; vma; vma = vma->vm_next)
+ if (vma->vm_userfaultfd_ctx.ctx == release_new_ctx)
+ vma->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX;
+ up_write(&mm->mmap_sem);
+
+ userfaultfd_ctx_put(release_new_ctx);
+ }
+
/*
* ctx may go away after this if the userfault pseudo fd is
* already released.