diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cgroup.c | 25 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 6 | ||||
| -rw-r--r-- | kernel/timer.c | 8 |
3 files changed, 27 insertions, 12 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 1f533877386..31e359be22a 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -3754,6 +3754,23 @@ static int cgroup_write_notify_on_release(struct cgroup *cgrp, } /* + * When dput() is called asynchronously, if umount has been done and + * then deactivate_super() in cgroup_free_fn() kills the superblock, + * there's a small window that vfs will see the root dentry with non-zero + * refcnt and trigger BUG(). + * + * That's why we hold a reference before dput() and drop it right after. + */ +static void cgroup_dput(struct cgroup *cgrp) +{ + struct super_block *sb = cgrp->root->sb; + + atomic_inc(&sb->s_active); + dput(cgrp->dentry); + deactivate_super(sb); +} + +/* * Unregister event and free resources. * * Gets called from workqueue. @@ -3773,7 +3790,7 @@ static void cgroup_event_remove(struct work_struct *work) eventfd_ctx_put(event->eventfd); kfree(event); - dput(cgrp->dentry); + cgroup_dput(cgrp); } /* @@ -4058,12 +4075,8 @@ static void css_dput_fn(struct work_struct *work) { struct cgroup_subsys_state *css = container_of(work, struct cgroup_subsys_state, dput_work); - struct dentry *dentry = css->cgroup->dentry; - struct super_block *sb = dentry->d_sb; - atomic_inc(&sb->s_active); - dput(dentry); - deactivate_super(sb); + cgroup_dput(css->cgroup); } static void init_cgroup_css(struct cgroup_subsys_state *css, diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index fa17855ca65..dc4db3228dc 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -555,9 +555,9 @@ int can_request_irq(unsigned int irq, unsigned long irqflags) return 0; if (irq_settings_can_request(desc)) { - if (desc->action) - if (irqflags & desc->action->flags & IRQF_SHARED) - canrequest =1; + if (!desc->action || + irqflags & desc->action->flags & IRQF_SHARED) + canrequest = 1; } irq_put_desc_unlock(desc, flags); return canrequest; diff --git a/kernel/timer.c b/kernel/timer.c index 15ffdb3f194..15bc1b41021 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -149,9 +149,11 @@ static unsigned long round_jiffies_common(unsigned long j, int cpu, /* now that we have rounded, subtract the extra skew again */ j -= cpu * 3; - if (j <= jiffies) /* rounding ate our timeout entirely; */ - return original; - return j; + /* + * Make sure j is still in the future. Otherwise return the + * unmodified value. + */ + return time_is_after_jiffies(j) ? j : original; } /** |