search for: wait_for_completion_kil

When we try to hot-remove a busy virtio-rng device from QEMU monitor, the device can't be hot-removed. Because virtio-rng driver hangs at wait_for_completion_killable(). This patch fixed the hang by completing have_data completion before unregistering a virtio-rng device. Signed-off-by: Amos Kong <akong at redhat.com> Cc: stable at vger.kernel.org --- drivers/char/hw_random/virtio-rng.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/ch...

When we try to hot-remove a busy virtio-rng device from QEMU monitor, the device can't be hot-removed. Because virtio-rng driver hangs at wait_for_completion_killable(). This patch fixed the hang by completing have_data completion before unregistering a virtio-rng device. Signed-off-by: Amos Kong <akong at redhat.com> Cc: stable at vger.kernel.org --- drivers/char/hw_random/virtio-rng.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/ch...

On (Wed) 06 Aug 2014 [16:05:41], Amos Kong wrote: > On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > > the device can't be hot-removed. Because virtio-rng driver hangs at > > wait_for_completion_killable(). > > > > This patch fixed the hang by completing have_data completion before > > unregistering a virtio-rng device. > > Hi Amit, > > Before applying this patch, it's blocking insider wait_for_completion_killable() > Applied this pa...

On (Wed) 06 Aug 2014 [16:05:41], Amos Kong wrote: > On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > > the device can't be hot-removed. Because virtio-rng driver hangs at > > wait_for_completion_killable(). > > > > This patch fixed the hang by completing have_data completion before > > unregistering a virtio-rng device. > > Hi Amit, > > Before applying this patch, it's blocking insider wait_for_completion_killable() > Applied this pa...

On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > the device can't be hot-removed. Because virtio-rng driver hangs at > wait_for_completion_killable(). > > This patch fixed the hang by completing have_data completion before > unregistering a virtio-rng device. Hi Amit, Before applying this patch, it's blocking insider wait_for_completion_killable() Applied this patch, wait_for_completion_killable() retu...

...d) 06 Aug 2014 [16:05:41], Amos Kong wrote: > > On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > > > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > > > the device can't be hot-removed. Because virtio-rng driver hangs at > > > wait_for_completion_killable(). > > > > > > This patch fixed the hang by completing have_data completion before > > > unregistering a virtio-rng device. > > > > Hi Amit, > > > > Before applying this patch, it's blocking insider wait_for_completion_killable()...

When we try to hot-remove a busy virtio-rng device from QEMU monitor, the device can't be hot-removed. Because virtio-rng driver hangs at wait_for_completion_killable(). This patch exits the waiting by completing have_data completion before unregistering, resets data_avail to avoid the hwrng core use wrong buffer bytes. Before real unregistering we should return -ENODEV for reading. When we hot-unplug the device, dd process in guest will exit. $ dd if=/...

When we try to hot-remove a busy virtio-rng device from QEMU monitor, the device can't be hot-removed. Because virtio-rng driver hangs at wait_for_completion_killable(). This patch exits the waiting by completing have_data completion before unregistering, resets data_avail to avoid the hwrng core use wrong buffer bytes. Before real unregistering we should return -ENODEV for reading. When we hot-unplug the device, dd process in guest will exit. $ dd if=/...

...truct virtrng_info *)rng->priv; - if (!busy) { - busy = true; - init_completion(&have_data); - register_buffer(buf, size); + if (!vi->busy) { + vi->busy = true; + init_completion(&vi->have_data); + register_buffer(vi, buf, size); } if (!wait) return 0; - ret = wait_for_completion_killable(&have_data); + ret = wait_for_completion_killable(&vi->have_data); if (ret < 0) return ret; - busy = false; + vi->busy = false; - return data_avail; + return vi->data_avail; } static void virtio_cleanup(struct hwrng *rng) { - if (busy) - wait_for_completion(&...

...truct virtrng_info *)rng->priv; - if (!busy) { - busy = true; - init_completion(&have_data); - register_buffer(buf, size); + if (!vi->busy) { + vi->busy = true; + init_completion(&vi->have_data); + register_buffer(vi, buf, size); } if (!wait) return 0; - ret = wait_for_completion_killable(&have_data); + ret = wait_for_completion_killable(&vi->have_data); if (ret < 0) return ret; - busy = false; + vi->busy = false; - return data_avail; + return vi->data_avail; } static void virtio_cleanup(struct hwrng *rng) { - if (busy) - wait_for_completion(&...

...7 @@ void kvmi_destroy_vm(struct kvm *kvm) > if (!ikvm) > return; > > + /* trigger socket shutdown - kvmi_recv() will start shutdown process */ > + kvmi_sock_shutdown(ikvm); > + > kvmi_put(kvm); > > /* wait for introspection resources to be released */ > wait_for_completion_killable(&kvm->kvmi_completed); > } > + This addition means that kvmi_destroy_vm should have called kvmi_end_introspection instead. In patch 1, kvmi_end_introspection should have been just kvmi_put, now this patch can add kvmi_sock_shutdown. Paolo

On (Wed) 10 Sep 2014 [14:11:36], Amos Kong wrote: > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > the device can't be hot-removed. Because virtio-rng driver hangs at > wait_for_completion_killable(). > > This patch exits the waiting by completing have_data completion before > unregistering, resets data_avail to avoid the hwrng core use wrong > buffer bytes. > > Signed-off-by: Amos Kong <akong at redhat.com> > Cc: stable at vger.kernel.org Reviewed-by: Amit...

On (Wed) 10 Sep 2014 [14:11:36], Amos Kong wrote: > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > the device can't be hot-removed. Because virtio-rng driver hangs at > wait_for_completion_killable(). > > This patch exits the waiting by completing have_data completion before > unregistering, resets data_avail to avoid the hwrng core use wrong > buffer bytes. > > Signed-off-by: Amos Kong <akong at redhat.com> > Cc: stable at vger.kernel.org Reviewed-by: Amit...

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1121540 When we try to hot-unplugging a busy virtio-rng device, the device can't be removed. And the reading process in guest gets stuck. Those two patches fixed this issue by completing have_data completion and preventing invalid reading. Thanks for the help of Amit. Cc: stable at vger.kernel.org V2: reset data_avail (Amit) adjust

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1121540 When we try to hot-unplugging a busy virtio-rng device, the device can't be removed. And the reading process in guest gets stuck. Those two patches fixed this issue by completing have_data completion and preventing invalid reading. Thanks for the help of Amit. Cc: stable at vger.kernel.org V2: reset data_avail (Amit) adjust

Hi Rusty, These are a few fixes for the virtio-rng driver. These were tested using the not-yet-upstream virtio-rng device patch to qemu: http://thread.gmane.org/gmane.comp.emulators.qemu/152668 Please apply. Amit Shah (5): virtio ids: fix comment for virtio-rng virtio: rng: allow tasks to be killed that are waiting for rng input virtio: rng: don't wait on host when module is going

Hi Rusty, These are a few fixes for the virtio-rng driver. These were tested using the not-yet-upstream virtio-rng device patch to qemu: http://thread.gmane.org/gmane.comp.emulators.qemu/152668 Please apply. Amit Shah (5): virtio ids: fix comment for virtio-rng virtio: rng: allow tasks to be killed that are waiting for rng input virtio: rng: don't wait on host when module is going

...andom/virtio-rng.c > @@ -65,7 +65,7 @@ static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait) > register_buffer(vi, buf, size); > } > > - if (!wait) > + if (!wait && !completion_done(&vi->have_data)) > return 0; > > ret = wait_for_completion_killable(&vi->have_data); > @@ -74,7 +74,7 @@ static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait) > > vi->busy = false; > > - return vi->data_avail; > + return min_t(size_t, size, vi->data_avail); > } > > static void virtio_c...

...andom/virtio-rng.c > @@ -65,7 +65,7 @@ static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait) > register_buffer(vi, buf, size); > } > > - if (!wait) > + if (!wait && !completion_done(&vi->have_data)) > return 0; > > ret = wait_for_completion_killable(&vi->have_data); > @@ -74,7 +74,7 @@ static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait) > > vi->busy = false; > > - return vi->data_avail; > + return min_t(size_t, size, vi->data_avail); > } > > static void virtio_c...

...if (vi->hwrng_removed) return -ENODEV; if (!vi->busy) { vi->busy = true; init_completion(&vi->have_data); register_buffer(vi, buf, size); } if (!wait) return 0; ret = wait_for_completion_killable(&vi->have_data); if (ret < 0) return ret; vi->busy = false; return vi->data_avail; } > > > if (!data_avail) { > > bytes_read = rng_get_data(current_rng, rng_buffer, > >...