diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2009-07-19 13:44:27 (GMT) |
|---|---|---|
| committer | Scott Wood <scottwood@freescale.com> | 2015-02-13 22:20:50 (GMT) |
| commit | ee5495719150e765366f7662d3db1a5e2c4b9196 (patch) | |
| tree | 70d67cf390dd21040d7c59ba3affcb9882007b12 /fs | |
| parent | bdcc0b93fdd54de443e8c1aed4419e09988cb707 (diff) | |
| download | linux-fsl-qoriq-ee5495719150e765366f7662d3db1a5e2c4b9196.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>
Diffstat (limited to 'fs')
| -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 7c3c0f6..f8214ee 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -315,8 +315,11 @@ 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 |