diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2013-03-26 20:30:17 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-04-05 10:16:36 -0700 |
| commit | 8cc034e4c1b7901787bbf72908bc584c055b5e09 (patch) | |
| tree | a6434b15e0fb353c800568358fcfd22ae50bad59 /drivers/tty | |
| parent | 19c85a53434ec90c1c6d6b0717e1eb37c5f2f84d (diff) | |
vt: synchronize_rcu() under spinlock is not nice...
commit e8cd81693bbbb15db57d3c9aa7dd90eda4842874 upstream.
vcs_poll_data_free() calls unregister_vt_notifier(), which calls
atomic_notifier_chain_unregister(), which calls synchronize_rcu().
Do it *after* we'd dropped ->f_lock.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/vt/vc_screen.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/tty/vt/vc_screen.c b/drivers/tty/vt/vc_screen.c index 66825c9f516..ab2320112bf 100644 --- a/drivers/tty/vt/vc_screen.c +++ b/drivers/tty/vt/vc_screen.c @@ -92,7 +92,7 @@ vcs_poll_data_free(struct vcs_poll_data *poll) static struct vcs_poll_data * vcs_poll_data_get(struct file *file) { - struct vcs_poll_data *poll = file->private_data; + struct vcs_poll_data *poll = file->private_data, *kill = NULL; if (poll) return poll; @@ -121,10 +121,12 @@ vcs_poll_data_get(struct file *file) file->private_data = poll; } else { /* someone else raced ahead of us */ - vcs_poll_data_free(poll); + kill = poll; poll = file->private_data; } spin_unlock(&file->f_lock); + if (kill) + vcs_poll_data_free(kill); return poll; } |