search for: kthread_should_stop

upstream commit 2ad49887150894b9ed6a87a76b409adceee6b074 Motivated from the commit, I found that cleaner_kthread() and transaction_kthread() can result similar error since these two function can exit even though kthread_should_stop() is not true. In order to resolve the bug, break statements are changed into continue statements in order to wait until kthread_should_stop() becomes true. --- a/fs/btrfs/async-thread.c +++ b/fs/btrfs/async-thread.c --- a/fs/btrfs/disk-io.c 2009-08-17 06:19:38.000000000 +0900 +++ a/fs/btrfs/...

virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing the task_struct::state collision typical of nesting of sleeping primitives See also http://lwn.net/A...

virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing the task_struct::state collision typical of nesting of sleeping primitives See also http://lwn.net/A...

...74878-17155-1-git-send-email-mst at redhat.com> virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing the task_struct::state collision typical of nesting of sleeping primitives See also http://lwn.net/A...

...74878-17155-1-git-send-email-mst at redhat.com> virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing the task_struct::state collision typical of nesting of sleeping primitives See also http://lwn.net/A...

virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing the task_struct::state collision typical of nesting of sleeping primitives See also http://lwn.net/A...

virtio balloon has this code: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); Which is a problem because towards_target() call might block after wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing the task_struct::state collision typical of nesting of sleeping primitives See also http://lwn.net/A...

...at redhat.com> wrote: > virtio balloon has this code: > wait_event_interruptible(vb->config_change, > (diff = towards_target(vb)) != 0 > || vb->need_stats_update > || kthread_should_stop() > || freezing(current)); > > Which is a problem because towards_target() call might block after > wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing > the task_struct::state collision typical of nesting of sleeping > primiti...

...at redhat.com> wrote: > virtio balloon has this code: > wait_event_interruptible(vb->config_change, > (diff = towards_target(vb)) != 0 > || vb->need_stats_update > || kthread_should_stop() > || freezing(current)); > > Which is a problem because towards_target() call might block after > wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing > the task_struct::state collision typical of nesting of sleeping > primiti...

On Thu, Feb 26, 2015 at 11:50:42AM +1030, Rusty Russell wrote: > Thomas Huth <thuth at linux.vnet.ibm.com> writes: > > Hi all, > > > > with the recent kernel 3.19, I get a kernel warning when I start my > > KVM guest on s390 with virtio balloon enabled: > > The deeper problem is that virtio_ccw_get_config just silently fails on > OOM. > > Neither

On Thu, Feb 26, 2015 at 11:50:42AM +1030, Rusty Russell wrote: > Thomas Huth <thuth at linux.vnet.ibm.com> writes: > > Hi all, > > > > with the recent kernel 3.19, I get a kernel warning when I start my > > KVM guest on s390 with virtio balloon enabled: > > The deeper problem is that virtio_ccw_get_config just silently fails on > OOM. > > Neither

.... 3. Use vmalloc to allocate netbk structures. Main Changes from v2: 1. Merge "group" and "idx" into "netif->mapping", therefore page_ext is not used now. 2. Put netbk_add_netif() and netbk_remove_netif() into __netif_up() and __netif_down(). 3. Change the usage of kthread_should_stop(). 4. Use __get_free_pages() to replace kzalloc(). 5. Modify the changes to netif_be_dbg(). 6. Use MODPARM_netback_kthread to determine whether using tasklet or kernel thread. 7. Put small fields in the front, and large arrays in the end of struct xen_netbk. 8. Add more checks in netif_page_release...

.../virtio_balloon.c index 5926826..9c76a06 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -190,7 +190,8 @@ static int balloon(void *_vballoon) try_to_freeze(); wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 - || kthread_should_stop()); + || kthread_should_stop() + || freezing(current)); if (diff > 0) fill_balloon(vb, diff); else if (diff < 0)

.../virtio_balloon.c index 5926826..9c76a06 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c @@ -190,7 +190,8 @@ static int balloon(void *_vballoon) try_to_freeze(); wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 - || kthread_should_stop()); + || kthread_should_stop() + || freezing(current)); if (diff > 0) fill_balloon(vb, diff); else if (diff < 0)

...> > virtio balloon has this code: > > wait_event_interruptible(vb->config_change, > > (diff = towards_target(vb)) != 0 > > || vb->need_stats_update > > || kthread_should_stop() > > || freezing(current)); > > > > Which is a problem because towards_target() call might block after > > wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing > > the task_struct::state collision typical of nesting...

...> > virtio balloon has this code: > > wait_event_interruptible(vb->config_change, > > (diff = towards_target(vb)) != 0 > > || vb->need_stats_update > > || kthread_should_stop() > > || freezing(current)); > > > > Which is a problem because towards_target() call might block after > > wait_event_interruptible sets task state to TAST_INTERRUPTIBLE, causing > > the task_struct::state collision typical of nesting...

....thread); > } > > kfree(dev->vblank); > @@ -447,6 +453,108 @@ void drm_vblank_cleanup(struct drm_device *dev) > dev->num_crtcs = 0; > } > > +static int vblank_work_thread(void *data) > +{ > + struct drm_vblank_crtc *vblank = data; > + > + while (!kthread_should_stop()) { > + struct drm_vblank_work *work, *next; > + LIST_HEAD(list); > + u64 count; > + int ret; > + > + spin_lock_irq(&vblank->dev->event_lock); > + > + ret = wait_event_interruptible_lock_irq(vblank->queue, > + kthread_should_stop() || > +...

...15bf8a>] __might_sleep+0x8a/0x98 [ 0.839778] ---[ end trace d27fcdfa27273d7c ]--- The problem seems to be this code in balloon() in drivers/virtio/virtio_balloon.c: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); wait_event_interruptible() sets the state of the current task to TASK_INTERRUPTIBLE, then checks the condition. The condition contains towards_target() which reads the virtio config space via virtio_cread(). On s390, this then triggers virtio_ccw_get_config() - and th...

...15bf8a>] __might_sleep+0x8a/0x98 [ 0.839778] ---[ end trace d27fcdfa27273d7c ]--- The problem seems to be this code in balloon() in drivers/virtio/virtio_balloon.c: wait_event_interruptible(vb->config_change, (diff = towards_target(vb)) != 0 || vb->need_stats_update || kthread_should_stop() || freezing(current)); wait_event_interruptible() sets the state of the current task to TASK_INTERRUPTIBLE, then checks the condition. The condition contains towards_target() which reads the virtio config space via virtio_cread(). On s390, this then triggers virtio_ccw_get_config() - and th...

...rget(struct virtio_balloon *vb) @@ -287,35 +292,22 @@ static void update_balloon_size(struct virtio_balloon *vb) &actual); } -static int balloon(void *_vballoon) +static void balloon(struct work_struct *work) { - struct virtio_balloon *vb = _vballoon; - - set_freezable(); - while (!kthread_should_stop()) { - s64 diff; - - try_to_freeze(); - wait_event_interruptible(vb->config_change, - (diff = towards_target(vb)) != 0 - || vb->need_stats_update - || kthread_should_stop() - || freezing(current)); - if (vb->need_stats_update) - stats_handle_request(vb); - if (di...