On Wed, Sep 21, 2011 at 10:58:13AM -0400, J. Bruce Fields wrote: > In setlease, we use i_writecount to decide whether we can give out a > read lease. > > In open, we break leases before incrementing i_writecount. > > There is therefore a window between the break lease and the i_writecount > increment when setlease could add a new read lease. > > This would leave us with a simultaneous write open and read lease, which > shouldn't happen. Al, could you apply this for 3.2, if you don't see any problem? (Patch 1 of this series only touches locks.c, and I'm queueing up such patches through the nfsd tree. Patches 3-6 I intend to rewrite, probably not in time for 3.2 unless I'm very lucky.) --b. > > Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx> > --- > fs/namei.c | 5 +---- > fs/open.c | 4 ++++ > 2 files changed, 5 insertions(+), 4 deletions(-) > > diff --git a/fs/namei.c b/fs/namei.c > index 2826db3..6ff59e5 100644 > --- a/fs/namei.c > +++ b/fs/namei.c > @@ -2044,10 +2044,7 @@ static int may_open(struct path *path, int acc_mode, int flag) > if (flag & O_NOATIME && !inode_owner_or_capable(inode)) > return -EPERM; > > - /* > - * Ensure there are no outstanding leases on the file. > - */ > - return break_lease(inode, flag); > + return 0; > } > > static int handle_truncate(struct file *filp) > diff --git a/fs/open.c b/fs/open.c > index f711921..22c41b5 100644 > --- a/fs/open.c > +++ b/fs/open.c > @@ -685,6 +685,10 @@ static struct file *__dentry_open(struct dentry *dentry, struct vfsmount *mnt, > if (error) > goto cleanup_all; > > + error = break_lease(inode, f->f_flags); > + if (error) > + goto cleanup_all; > + > if (!open && f->f_op) > open = f->f_op->open; > if (open) { > -- > 1.7.4.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html