diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2009-07-19 08:44:27 -0500 |
|---|---|---|
| committer | Gary S. Robertson <gary.robertson@linaro.org> | 2014-05-07 08:56:08 -0500 |
| commit | b8a754d2ec54b8e4adfab40898ad44b227471dc7 (patch) | |
| tree | 5faba4ea9610ed6251eb5d94bb149ada12e04466 /fs | |
| parent | 1c5f53e4f09600e218f044fe55a85a5de32bf9e4 (diff) | |
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 a45ba4f267fe..1939f6ab3a96 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 |