search for: have_data

....c index 2ce0e22..12e242b 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -25,88 +25,108 @@ #include <linux/virtio_rng.h> #include <linux/module.h> -static struct virtqueue *vq; -static unsigned int data_avail; -static DECLARE_COMPLETION(have_data); -static bool busy; + +struct virtrng_info { + struct virtio_device *vdev; + struct hwrng hwrng; + struct virtqueue *vq; + unsigned int data_avail; + struct completion have_data; + bool busy; +}; static void random_recv_done(struct virtqueue *vq) { + struct virtrng_info *vi = vq->vdev->p...

....c index 2ce0e22..12e242b 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -25,88 +25,108 @@ #include <linux/virtio_rng.h> #include <linux/module.h> -static struct virtqueue *vq; -static unsigned int data_avail; -static DECLARE_COMPLETION(have_data); -static bool busy; + +struct virtrng_info { + struct virtio_device *vdev; + struct hwrng hwrng; + struct virtqueue *vq; + unsigned int data_avail; + struct completion have_data; + bool busy; +}; static void random_recv_done(struct virtqueue *vq) { + struct virtrng_info *vi = vq->vdev->p...

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/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-r...

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/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-r...

...ng 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() returns 0, &g...

...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() returns 0, > and vi->data_avail becom...

...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() returns 0, > and vi->data_avail becom...

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() returns 0, and vi->data_avail becomes 0, then rng_get_date() will retu...

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 unregister order V3: split patch, update commitlog Amos Kong (2): virtio-rng: fix stuck of hot-unplugging busy device virtio-rng: skip reading when we...

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 unregister order V3: split patch, update commitlog Amos Kong (2): virtio-rng: fix stuck of hot-unplugging busy device virtio-rng: skip reading when we...

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=/dev/hwrng of=/dev/null dd: error reading ?/dev/hwrng?: No su...

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=/dev/hwrng of=/dev/null dd: error reading ?/dev/hwrng?: No su...

...) >>>> return -ENODEV; >>>> >>>> + /* >>>> + * If the previous call was non-blocking, we may have got some >>>> + * randomness already. >>>> + */ >>>> + if (vi->busy && completion_done(&vi->have_data)) { >>>> + unsigned int len; >>>> + >>>> + vi->busy = false; >>>> + len = vi->data_avail > size ? size : vi->data_avail; >>>> + vi->data_avail -= len; >> >> You don't need to modify data_avail. As busy is...

...a segment with the scsi command block, and before - * the normal inhdr we put the sense data and the inhdr with additional status - * information. - */ -#ifdef CONFIG_VIRTIO_BLK_SCSI -static int virtblk_add_req_scsi(struct virtqueue *vq, struct virtblk_req *vbr, - struct scatterlist *data_sg, bool have_data) -{ - struct scatterlist hdr, status, cmd, sense, inhdr, *sgs[6]; - unsigned int num_out = 0, num_in = 0; - - sg_init_one(&hdr, &vbr->out_hdr, sizeof(vbr->out_hdr)); - sgs[num_out++] = &hdr; - sg_init_one(&cmd, vbr->sreq.cmd, vbr->sreq.cmd_len); - sgs[num_out++] = &c...

...02110-1301 USA + */ +#include <linux/err.h> +#include <linux/hw_random.h> +#include <linux/scatterlist.h> +#include <linux/spinlock.h> +#include <linux/virtio.h> +#include <linux/virtio_rng.h> + +static struct virtqueue *vq; +static u32 random_data; +static bool have_data; + +static bool random_recv_done(struct virtqueue *vq) +{ + have_data = true; + + /* Don't suppress callbacks: there can't be any more since we + * have used up the only buffer. */ + return true; +} + +static void register_buffer(void) +{ + struct scatterlist sg; + + sg_i...

...02110-1301 USA + */ +#include <linux/err.h> +#include <linux/hw_random.h> +#include <linux/scatterlist.h> +#include <linux/spinlock.h> +#include <linux/virtio.h> +#include <linux/virtio_rng.h> + +static struct virtqueue *vq; +static u32 random_data; +static bool have_data; + +static bool random_recv_done(struct virtqueue *vq) +{ + have_data = true; + + /* Don't suppress callbacks: there can't be any more since we + * have used up the only buffer. */ + return true; +} + +static void register_buffer(void) +{ + struct scatterlist sg; + + sg_i...

I received two mails about faile to apply patches to 3.16-stable tree: FAILED: patch "[PATCH] virtio-rng: skip reading when we start to remove the device" failed to apply to 3.16-stable tree FAILED: patch "[PATCH] virtio-rng: fix stuck of hot-unplugging busy device" failed to apply to 3.16-stable tree Amit already backported two patches for 3.16-stable, then cherry-pick of my

I received two mails about faile to apply patches to 3.16-stable tree: FAILED: patch "[PATCH] virtio-rng: skip reading when we start to remove the device" failed to apply to 3.16-stable tree FAILED: patch "[PATCH] virtio-rng: fix stuck of hot-unplugging busy device" failed to apply to 3.16-stable tree Amit already backported two patches for 3.16-stable, then cherry-pick of my

...w_random/virtio-rng.c > +++ b/drivers/char/hw_random/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, siz...

...w_random/virtio-rng.c > +++ b/drivers/char/hw_random/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, siz...