| Message ID | 1708398727-46308-1-git-send-email-wangyunjian@huawei.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 2a770cdc4382b457ca3d43d03f0f0064f905a0d0 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] tun: Fix xdp_rxq_info's queue_index when detaching | expand |
Yunjian Wang wrote: > When a queue(tfile) is detached, we only update tfile's queue_index, > but do not update xdp_rxq_info's queue_index. This patch fixes it. > > Fixes: 8bf5c4ee1889 ("tun: setup xdp_rxq_info") > Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> > --- > drivers/net/tun.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c > index bc80fc1d576e..be37235af55d 100644 > --- a/drivers/net/tun.c > +++ b/drivers/net/tun.c > @@ -652,6 +652,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) > tun->tfiles[tun->numqueues - 1]); > ntfile = rtnl_dereference(tun->tfiles[index]); > ntfile->queue_index = index; > + ntfile->xdp_rxq.queue_index = index; > rcu_assign_pointer(tun->tfiles[tun->numqueues - 1], > NULL); Does it matter that this value is stale when undetached? It is replaced in tun_attach if previously attached: /* Re-attach detached tfile, updating XDP queue_index */ WARN_ON(!xdp_rxq_info_is_reg(&tfile->xdp_rxq)); if (tfile->xdp_rxq.queue_index != tfile->queue_index) tfile->xdp_rxq.queue_index = tfile->queue_index;
> -----Original Message----- > From: Willem de Bruijn [mailto:willemdebruijn.kernel@gmail.com] > Sent: Tuesday, February 20, 2024 11:59 PM > To: wangyunjian <wangyunjian@huawei.com>; > willemdebruijn.kernel@gmail.com; jasowang@redhat.com; kuba@kernel.org; > davem@davemloft.net > Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; > brouer@redhat.com; xudingke <xudingke@huawei.com>; wangyunjian > <wangyunjian@huawei.com> > Subject: Re: [PATCH net] tun: Fix xdp_rxq_info's queue_index when detaching > > Yunjian Wang wrote: > > When a queue(tfile) is detached, we only update tfile's queue_index, > > but do not update xdp_rxq_info's queue_index. This patch fixes it. > > > > Fixes: 8bf5c4ee1889 ("tun: setup xdp_rxq_info") > > Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> > > --- > > drivers/net/tun.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c index > > bc80fc1d576e..be37235af55d 100644 > > --- a/drivers/net/tun.c > > +++ b/drivers/net/tun.c > > @@ -652,6 +652,7 @@ static void __tun_detach(struct tun_file *tfile, bool > clean) > > tun->tfiles[tun->numqueues - 1]); > > ntfile = rtnl_dereference(tun->tfiles[index]); > > ntfile->queue_index = index; > > + ntfile->xdp_rxq.queue_index = index; > > rcu_assign_pointer(tun->tfiles[tun->numqueues - 1], > > NULL); > > Does it matter that this value is stale when undetached? Yes, the detach tfile'queue_index is not important because the re-attach will update. But this patch is to fix the 'ntfile'(that replaces the detach tfile)'s queue_index, it is wrong. Thanks > > It is replaced in tun_attach if previously attached: > > /* Re-attach detached tfile, updating XDP queue_index */ > WARN_ON(!xdp_rxq_info_is_reg(&tfile->xdp_rxq)); > > if (tfile->xdp_rxq.queue_index != tfile->queue_index) > tfile->xdp_rxq.queue_index = tfile->queue_index;
wangyunjian wrote: > > > > -----Original Message----- > > From: Willem de Bruijn [mailto:willemdebruijn.kernel@gmail.com] > > Sent: Tuesday, February 20, 2024 11:59 PM > > To: wangyunjian <wangyunjian@huawei.com>; > > willemdebruijn.kernel@gmail.com; jasowang@redhat.com; kuba@kernel.org; > > davem@davemloft.net > > Cc: netdev@vger.kernel.org; linux-kernel@vger.kernel.org; > > brouer@redhat.com; xudingke <xudingke@huawei.com>; wangyunjian > > <wangyunjian@huawei.com> > > Subject: Re: [PATCH net] tun: Fix xdp_rxq_info's queue_index when detaching > > > > Yunjian Wang wrote: > > > When a queue(tfile) is detached, we only update tfile's queue_index, > > > but do not update xdp_rxq_info's queue_index. This patch fixes it. > > > > > > Fixes: 8bf5c4ee1889 ("tun: setup xdp_rxq_info") > > > Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> > > > --- > > > drivers/net/tun.c | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/drivers/net/tun.c b/drivers/net/tun.c index > > > bc80fc1d576e..be37235af55d 100644 > > > --- a/drivers/net/tun.c > > > +++ b/drivers/net/tun.c > > > @@ -652,6 +652,7 @@ static void __tun_detach(struct tun_file *tfile, bool > > clean) > > > tun->tfiles[tun->numqueues - 1]); > > > ntfile = rtnl_dereference(tun->tfiles[index]); > > > ntfile->queue_index = index; > > > + ntfile->xdp_rxq.queue_index = index; > > > rcu_assign_pointer(tun->tfiles[tun->numqueues - 1], > > > NULL); > > > > Does it matter that this value is stale when undetached? > > Yes, the detach tfile'queue_index is not important because the re-attach will update. > But this patch is to fix the 'ntfile'(that replaces the detach tfile)'s queue_index, it is wrong. Oh yes. This looks correct to me. Let's cc: the author of the patch listed as Fixed too. > > Thanks > > > > It is replaced in tun_attach if previously attached: > > > > /* Re-attach detached tfile, updating XDP queue_index */ > > WARN_ON(!xdp_rxq_info_is_reg(&tfile->xdp_rxq)); > > > > if (tfile->xdp_rxq.queue_index != tfile->queue_index) > > tfile->xdp_rxq.queue_index = tfile->queue_index;
Hello: This patch was applied to netdev/net.git (main) by Jakub Kicinski <kuba@kernel.org>: On Tue, 20 Feb 2024 11:12:07 +0800 you wrote: > When a queue(tfile) is detached, we only update tfile's queue_index, > but do not update xdp_rxq_info's queue_index. This patch fixes it. > > Fixes: 8bf5c4ee1889 ("tun: setup xdp_rxq_info") > Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> > --- > drivers/net/tun.c | 1 + > 1 file changed, 1 insertion(+) Here is the summary with links: - [net] tun: Fix xdp_rxq_info's queue_index when detaching https://git.kernel.org/netdev/net/c/2a770cdc4382 You are awesome, thank you!
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index bc80fc1d576e..be37235af55d 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -652,6 +652,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) tun->tfiles[tun->numqueues - 1]); ntfile = rtnl_dereference(tun->tfiles[index]); ntfile->queue_index = index; + ntfile->xdp_rxq.queue_index = index; rcu_assign_pointer(tun->tfiles[tun->numqueues - 1], NULL);
When a queue(tfile) is detached, we only update tfile's queue_index, but do not update xdp_rxq_info's queue_index. This patch fixes it. Fixes: 8bf5c4ee1889 ("tun: setup xdp_rxq_info") Signed-off-by: Yunjian Wang <wangyunjian@huawei.com> --- drivers/net/tun.c | 1 + 1 file changed, 1 insertion(+)