* [PATCH net 1/2] tun: handle ubuf refcount correctly when meet erros
@ 2016-11-30 5:17 Jason Wang
2016-11-30 5:17 ` [PATCH net 2/2] macvtap: " Jason Wang
2016-11-30 13:57 ` [PATCH net 1/2] tun: " Michael S. Tsirkin
0 siblings, 2 replies; 4+ messages in thread
From: Jason Wang @ 2016-11-30 5:17 UTC (permalink / raw)
To: netdev, linux-kernel; +Cc: mst, wangyunjian, Jason Wang
We trigger uarg->callback() immediately after we decide do datacopy
even if caller want to do zerocopy. This will cause the callback
(vhost_net_zerocopy_callback) decrease the refcount. But when we meet
an error afterwards, the error handling in vhost handle_tx() will try
to decrease it again. This is wrong and fix this by delay the
uarg->callback() until we're sure there's no errors.
Reported-by: wangyunjian <wangyunjian@huawei.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
The patch is needed for -stable.
---
drivers/net/tun.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 8093e39..db6acec 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1246,13 +1246,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
if (zerocopy)
err = zerocopy_sg_from_iter(skb, from);
- else {
+ else
err = skb_copy_datagram_from_iter(skb, 0, from, len);
- if (!err && msg_control) {
- struct ubuf_info *uarg = msg_control;
- uarg->callback(uarg, false);
- }
- }
if (err) {
this_cpu_inc(tun->pcpu_stats->rx_dropped);
@@ -1298,6 +1293,9 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
skb_shinfo(skb)->destructor_arg = msg_control;
skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
+ } else if (msg_control) {
+ struct ubuf_info *uarg = msg_control;
+ uarg->callback(uarg, false);
}
skb_reset_network_header(skb);
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH net 2/2] macvtap: handle ubuf refcount correctly when meet erros
2016-11-30 5:17 [PATCH net 1/2] tun: handle ubuf refcount correctly when meet erros Jason Wang
@ 2016-11-30 5:17 ` Jason Wang
2016-11-30 13:58 ` Michael S. Tsirkin
2016-11-30 13:57 ` [PATCH net 1/2] tun: " Michael S. Tsirkin
1 sibling, 1 reply; 4+ messages in thread
From: Jason Wang @ 2016-11-30 5:17 UTC (permalink / raw)
To: netdev, linux-kernel; +Cc: mst, wangyunjian, Jason Wang
We trigger uarg->callback() immediately after we decide do datacopy
even if caller want to do zerocopy. This will cause the callback
(vhost_net_zerocopy_callback) decrease the refcount. But when we meet
an error afterwards, the error handling in vhost handle_tx() will try
to decrease it again. This is wrong and fix this by delay the
uarg->callback() until we're sure there's no errors.
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
The patch is needed for -stable.
---
drivers/net/macvtap.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index bceca28..7869b06 100644
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -742,13 +742,8 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
if (zerocopy)
err = zerocopy_sg_from_iter(skb, from);
- else {
+ else
err = skb_copy_datagram_from_iter(skb, 0, from, len);
- if (!err && m && m->msg_control) {
- struct ubuf_info *uarg = m->msg_control;
- uarg->callback(uarg, false);
- }
- }
if (err)
goto err_kfree;
@@ -779,7 +774,11 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
skb_shinfo(skb)->destructor_arg = m->msg_control;
skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
+ } else if (m && m->msg_control) {
+ struct ubuf_info *uarg = m->msg_control;
+ uarg->callback(uarg, false);
}
+
if (vlan) {
skb->dev = vlan->dev;
dev_queue_xmit(skb);
--
2.7.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH net 1/2] tun: handle ubuf refcount correctly when meet erros
2016-11-30 5:17 [PATCH net 1/2] tun: handle ubuf refcount correctly when meet erros Jason Wang
2016-11-30 5:17 ` [PATCH net 2/2] macvtap: " Jason Wang
@ 2016-11-30 13:57 ` Michael S. Tsirkin
1 sibling, 0 replies; 4+ messages in thread
From: Michael S. Tsirkin @ 2016-11-30 13:57 UTC (permalink / raw)
To: Jason Wang; +Cc: netdev, linux-kernel, wangyunjian
On Wed, Nov 30, 2016 at 01:17:51PM +0800, Jason Wang wrote:
> We trigger uarg->callback() immediately after we decide do datacopy
> even if caller want to do zerocopy. This will cause the callback
> (vhost_net_zerocopy_callback) decrease the refcount. But when we meet
> an error afterwards, the error handling in vhost handle_tx() will try
> to decrease it again. This is wrong and fix this by delay the
> uarg->callback() until we're sure there's no errors.
>
> Reported-by: wangyunjian <wangyunjian@huawei.com>
> Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> The patch is needed for -stable.
> ---
> drivers/net/tun.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/tun.c b/drivers/net/tun.c
> index 8093e39..db6acec 100644
> --- a/drivers/net/tun.c
> +++ b/drivers/net/tun.c
> @@ -1246,13 +1246,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
>
> if (zerocopy)
> err = zerocopy_sg_from_iter(skb, from);
> - else {
> + else
> err = skb_copy_datagram_from_iter(skb, 0, from, len);
> - if (!err && msg_control) {
> - struct ubuf_info *uarg = msg_control;
> - uarg->callback(uarg, false);
> - }
> - }
>
> if (err) {
> this_cpu_inc(tun->pcpu_stats->rx_dropped);
> @@ -1298,6 +1293,9 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
> skb_shinfo(skb)->destructor_arg = msg_control;
> skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
> skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
> + } else if (msg_control) {
> + struct ubuf_info *uarg = msg_control;
> + uarg->callback(uarg, false);
> }
>
> skb_reset_network_header(skb);
> --
> 2.7.4
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net 2/2] macvtap: handle ubuf refcount correctly when meet erros
2016-11-30 5:17 ` [PATCH net 2/2] macvtap: " Jason Wang
@ 2016-11-30 13:58 ` Michael S. Tsirkin
0 siblings, 0 replies; 4+ messages in thread
From: Michael S. Tsirkin @ 2016-11-30 13:58 UTC (permalink / raw)
To: Jason Wang; +Cc: netdev, linux-kernel, wangyunjian
On Wed, Nov 30, 2016 at 01:17:52PM +0800, Jason Wang wrote:
> We trigger uarg->callback() immediately after we decide do datacopy
> even if caller want to do zerocopy. This will cause the callback
> (vhost_net_zerocopy_callback) decrease the refcount. But when we meet
> an error afterwards, the error handling in vhost handle_tx() will try
> to decrease it again. This is wrong and fix this by delay the
> uarg->callback() until we're sure there's no errors.
>
> Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
> ---
> The patch is needed for -stable.
> ---
> drivers/net/macvtap.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
> index bceca28..7869b06 100644
> --- a/drivers/net/macvtap.c
> +++ b/drivers/net/macvtap.c
> @@ -742,13 +742,8 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
>
> if (zerocopy)
> err = zerocopy_sg_from_iter(skb, from);
> - else {
> + else
> err = skb_copy_datagram_from_iter(skb, 0, from, len);
> - if (!err && m && m->msg_control) {
> - struct ubuf_info *uarg = m->msg_control;
> - uarg->callback(uarg, false);
> - }
> - }
>
> if (err)
> goto err_kfree;
> @@ -779,7 +774,11 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
> skb_shinfo(skb)->destructor_arg = m->msg_control;
> skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
> skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
> + } else if (m && m->msg_control) {
> + struct ubuf_info *uarg = m->msg_control;
> + uarg->callback(uarg, false);
> }
> +
> if (vlan) {
> skb->dev = vlan->dev;
> dev_queue_xmit(skb);
> --
> 2.7.4
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-11-30 13:58 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2016-11-30 5:17 [PATCH net 1/2] tun: handle ubuf refcount correctly when meet erros Jason Wang
2016-11-30 5:17 ` [PATCH net 2/2] macvtap: " Jason Wang
2016-11-30 13:58 ` Michael S. Tsirkin
2016-11-30 13:57 ` [PATCH net 1/2] tun: " Michael S. Tsirkin
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