diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2009-07-19 13:44:27 (GMT) |
|---|---|---|
| committer | Emil Medve <Emilian.Medve@Freescale.com> | 2013-04-30 08:17:19 (GMT) |
| commit | 0c577d12cd3c98517fd06e1fd5778a485e1f2acf (patch) | |
| tree | 3a50e022f18598d0ade72c0c7e290b3f8685722f | |
| parent | 27bcea12186fc98629b3bfab800f05a9114b4e5b (diff) | |
| download | linux-fsl-qoriq-0c577d12cd3c98517fd06e1fd5778a485e1f2acf.tar.xz | |
fs: namespace preemption fix
On RT we cannot loop with preemption disabled here as
mnt_make_readonly() might have been preempted. We can safely enable
preemption while waiting for MNT_WRITE_HOLD to be cleared. Safe on !RT
as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| -rw-r--r-- | fs/namespace.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 5dd7709..c03d460 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -313,8 +313,11 @@ int __mnt_want_write(struct vfsmount *m) * incremented count after it has set MNT_WRITE_HOLD. */ smp_mb(); - while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) + while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) { + preempt_enable(); cpu_relax(); + preempt_disable(); + } /* * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will * be set to match its requirements. So we must not load that until |